Cancer and Treatment Tips

Dentistry and Orthodontics

2011-06-20T03:50:00.001-07:00

Orthodontics, orthodontia, or orthodonture (from Greek orthos "straight or proper"; and odous "tooth") is the first specialty of dentistry that is concerned with the study and treatment of malocclusions (improper bites), which may be a result of tooth irregularity, disproportionate jaw relationships, or both. Orthodontic treatment can focus on dental displacement only, or can deal with the control and modification of facial growth. In the latter case it is better defined as "dentofacial orthopaedics". Orthodontic treatment can be carried out for purely aesthetic reasons with regards to improving the general appearance of patients' teeth. However, there are orthodontists who work on reconstructing the entire face rather than focusing exclusively on teeth.

History of orthodontics

Edward Angle was the first orthodontist—the first dentist to limit his practice to orthodontics only. He is considered the "father of modern orthodontics."

Modern Orthodontics

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Methods

For comprehensive orthodontic treatment, most commonly, metal wires (Juste) are inserted into orthodontic brackets (see dental braces), which can be made from stainless steel or a more aesthetic ceramic material. The wires interact with the brackets to move teeth into the desired positions. Other methods may include invisalign. Invisalign consists of clear plastic aligners that 'level and align', but require more patient compliance than traditional braces.

Dental braces, with a powerchain, removed after completion of treatment.

Additional components—including removable appliances ("plates"), headgear, expansion appliances, and many other devices—may also be used to move teeth and jaw bones. Functional appliances, for example, are used in growing patients (age 5 to 14) with the aim of modifying the jaw dimensions and relationship if these are altered. This therapy, termed Dentofacial Orthopedics, is frequently followed by fixed multibracket therapy ("full braces") to align the teeth and refine the occlusion.

Hawley retainers are the most common type of retainers. This picture shows retainers for the top and bottom of the mouth.

Orthodontics is the study of dentistry that is concerned with the treatment of improper bites, and crooked teeth. Orthodontic treatment can help fix your teeth and set them in the right place. Orthodontists usually use braces and retainers to set your teeth.^[2] There are, however, orthodontists who work on reconstructing the entire face rather than focusing exclusively on teeth. After a course of active orthodontic treatment, patients will typically wear retainers, which maintain the teeth in their improved positions while surrounding bone reforms around them. The retainers are generally worn full-time for a short period, perhaps six months to a year, then part-time (typically, nightly during sleep) for as long as the orthodontist recommends. It is possible for the teeth to stay aligned without regular retainer wear. However, there are many reasons teeth will crowd as a person ages, whether or not the individual ever experienced orthodontic treatment; thus there is no guarantee that teeth will stay aligned without retention. For this reason, many orthodontists prescribe part-time retainer wear for many years after orthodontic treatment.

Diagnosis and treatment planning

In diagnosis and treatment planning, the orthodontist must (1) recognize the various characteristics of a malocclusion or dentofacial deformity; (2) define the nature of the problem, including the etiology if possible;(3) design a treatment strategy based on the specific needs and desires of the individual; and (4) present the treatment strategy to the patient in such a way that the patient fully understands the ramifications of his/her decision.^[3]
The New York Times has recently written that orthodontists are using Cone Beam CT too much in the diagnosis and treatment of orthodontic patients, leading to an unnecessary increased risk of cancer.^[4]

Training

Orthodontics was the first recognised specialty field within dentistry. Many countries have their own systems for training and registering orthodontic specialists. A two to three year period of full-time post-graduate study is required for a dentist to qualify as an orthodontist.

United States of America

The applicant must have completed or be a full-time student/resident in an advanced education program in orthodontics and dentofacial orthopedics which is approved by the Commission on Dental Accreditation of the ADA. The "Advanced Standing Student - Standard #5," as recognized by the Commission of Dental Education, is eligible to make application upon the completion of their program. The applicant will submit with the application either a copy of the graduate orthodontic degree/certificate or a letter from the Program Director verifying the applicant's status.^[5]
Certification Process
1. Application
2. Written Examination
3. Clinical Examination
4. Annual Fee

Europe

In the United Kingdom, this training period lasts three years, after completion of a membership from a Royal College. A further two years is then completed to train to consultant level, after which a fellowship examination from the Royal College is sat. In other parts of Europe, a similar pattern is followed. It is always worth contacting the professional body responsible for registering orthodontists to ensure that the orthodontist you wish to consult is a recognised specialist.

Canada

A number of dental schools and hospitals offer advanced education in the specialty of Orthodontics to dentists seeking postgraduate education. The courses range from two to three years (with the majority being 3 years) of full-time classes in the theoretical and practical aspects of orthodontics together with clinical experience. Generally, admission is based on an application process followed by an extensive interviewing process by the institution, in order to select the best candidates. Candidates usually have to contact the individual school directly for the application process.

India

In India, many dental colleges affiliated to universities offer orthodontics as specialization in Master of Dental Surgery ( M.D.S ) programme.The minimum qualification for M.D.S is Bachelor of Dental Surgery ( B.D.S ). The present course for MDS in Orthodontics stands at 10 years in all dental colleges in India which are recognised by the Dental Council of India.
The Indian Orthodontic Society was established in 1965. The Academy of Fixed Orthodontics, (AFO),^[6] established in 2008, represents GP's and members from other dental specialties who practices orthodontics. AFO offers certification courses in Fixed Orthodontics for General Practitioners in Dentistry. Indian Orthodontic Society, the official body of orthodontists in India does not recognize non orthodontists who have taken certificate courses from non recognized bodies as Orthodontists. Only orthodontists who have done masters in orthodontics from recognised schools are allowed as members of Indian Orthodontic Society.

Dr. Saad Salahuddin

Saad Salahuddin attended Baqai Dental School, University of Karachi , Pakistan and met his wife, Reem, who is an Orthodontist. They moved to the United Kingdom for 5 years where he completed the Oral & Maxillofacial Surgery Residency and then Fellowship from the Royal College of Surgeons of England, in Oral Medicine and Oral Surgery.

He then moved to California in 2003 and undertook the D.D.S. program with advance standing at the Arthur A Dugoni, School of Dentistry, University of the Pacific, San Francisco.
He had been in private practice in the Financial District of San Francisco since 2005 at Embarcadero Dentistry and was featured in The “San Francisco” magazine as one of the “Top 10” Health care providers in San Francsico Bay Area.
Dr Salahuddin has taught Local Anesthesia to Dental and Medical Residents in England and received and award at an International Dental Conference for presenting on “ Oral Submucus Fibrosis” a Precancerous Oral condition.
He has been trained in Dental Implants from one of the Country’s top Implant Institute In Florida, PIKOS Implant Institute, Tampa Florida.
(www.pikosinstitute.com)
He is also trained in LASERs, Hospital Dentistry, Bone Grafting and Oro Facial Trauma.
He has been in the dental field for more than 15 years practicing and sharing his philosophy of providing the highest quality oral health care. He practices a full range of General and Cosmetic Dentistry with an emphasis on Oral & Periodontal Surgery including Dental Implants. He also has special training is treating patients with “Temporo-Mandibular Joint Disorders (TMD)” & “Snoring Problems”

He moved to The Woodlands in April 2009 and while establishing “Dentistry & Orthodontics” has been involved in community service by providing dental care to the Harris County Hospital District.
His professional memberships are :
American Dental Association (ADA)
California Dental Association (CDA)
San Francisco Dental Society (SFDS)
British Association of Oral & Maxillofacial Surgeons (BAOMS)
Society for Anesthesia and Analgesia in Dentistry (SAAD)
Academy of General Dentistry (AGD)
Dr Salahuddin will be an In-network Dental Insurance provider for the following PPO plans;

Aetna,
Ameritas
Blue cross/ Blue shield
Careington
Cigna
Delta Dental
DenteMax
Dental Select

Guardian
Humana
Metife
Principal
Safeguard
United Concordia
UniCare
United Health

He plays competitive squash and cricket and enjoys music, traveling, and playing tennis with his family.

Anti Aging

2011-06-20T03:46:00.000-07:00

Anti Aging

It was not until my grandmother reached the age of 62 years when she started asking what the treatment for “crepey” skin is.
What is crepey skin?
Crepey skin is an ugly consequence of aging. People of more advanced age are prone to developing this condition. It is largely because of the natural aging process. This does not mean, however, that you cannot do anything to minimize or prevent crepey skin from developing later. Let us find out how this develops first.
Our skin is an amazing natural production line. It is the largest organ in the body and it serves as our first line of defense. It is constantly exposed to varying environmental factors, substances and organisms every single day.
In order to perform its functions well, the skin layer contains different mechanisms and rejuvenating processes to help heal and renew itself. This is aimed at maintaining optimal performance.
The skin contains collagen bundles, which are combination of collagen and elastin molecules. Collagen and elastin are naturally produced protein types responsible in providing strength and elasticity of the skin surface. Our skin alone can produce and replenish its own collagen and elastin mass.
As we advance in age, however, the body can no longer optimally regenerate to replace these dying and damaged proteins. This consequently leads to the gradual reduction in collagen bundle content beneath the skin layers. When this happens, the skin surface starts to sag, becomes loose and eventually develops what we called “crepey” skin texture.
Crepey skin is a loose fold and wrinkle found usually below our neck, arms and sometimes in our legs. It can also be found in many other parts of the body mostly exposed particularly to the sun.
As I had mentioned earlier, crepey skin is caused by the substantial loses in the collagen bundle content beneath your skin. In addition, since our body alone can replenish its own supply of collagen and elastin, all we need to do is to help our body attain maximal regeneration performance.
Dermal fillers, laser surgery and a lot other procedures, even if not very invasive, do not provide a lasting treatment for such problematic skin conditions. Most of them require repeated sessions, which make them more expensive. Truth to tell, there are various skin care products available in the market that help you regain firm and smooth skin.
Look out for these natural substances
These products are actually made of natural essential substance. You probably have heard a lot about Cynergy TK and Hyaluronic acid and their effectiveness.
Cynergy TK is a vitamin-like substance taken from the wool of the specific breed of sheep raised in New Zealand. This substance is known to help the body boost collagen production.
Hyaluronic acid acts as glue that binds together collagen and elastin molecules. It is richly found in Phytessence Wakame, exotic kelp found only in Japan Sea. Wakame is also rich in anti-oxidants and other essential micronutrients that help the skin rejuvenate itself. Many tests had been conducted showing Phytessence Wakame as an effective treatment to crepey skin.
Treating crepey skin is not difficult as long as you understand how it develops. Try using products containing these natural substances. You will surely find your skin getting smoother and more great looking too!
It was not until my grandmother reached the age of 62 years when she started asking what the treatment for “crepey” skin is.

Cancer Treatment Tips

2011-06-20T03:12:00.000-07:00

Cancer Treatement Tips
Cancer /ˈkænsər/ ( listen) (medical term: malignant neoplasm) is a class of diseases in which a group of cells display uncontrolled growth, invasion that intrudes upon and destroys adjacent tissues, and sometimes metastasis, or spreading to other locations in the body via lymph or blood. These three malignant properties of cancers differentiate them from benign tumors, which do not invade or metastasize.
Researchers divide the causes of cancer into two groups: those with an environmental cause and those with a hereditary genetic cause. Cancer is primarily an environmental disease, though genetics influence the risk of some cancers.^[1] Common environmental factors leading to cancer include: tobacco, diet and obesity, infections, radiation, lack of physical activity, and environmental pollutants.^[1] These environmental factors cause or enhance abnormalities in the genetic material of cells.^[2] Cell reproduction is an extremely complex process that is normally tightly regulated by several classes of genes, including oncogenes and tumor suppressor genes. Hereditary or acquired abnormalities in these regulatory genes can lead to the development of cancer. A small percentage of cancers, approximately five to ten percent, are entirely hereditary.
The presence of cancer can be suspected on the basis of symptoms, or findings on radiology. Definitive diagnosis of cancer, however, requires the microscopic examination of a biopsy specimen. Most cancers can be treated. Possible treatments include chemotherapy, radiotherapy and surgery. The prognosis is influenced by the type of cancer and the extent of disease. While cancer can affect people of all ages, and a few types of cancer are more common in children, the overall risk of developing cancer increases with age. In 2007 cancer caused about 13% of all human deaths worldwide (7.9 million). Rates are rising as more people live to an old age and lifestyles change in the developing world.^[3]

Classification

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Further information: List of cancer types and List of oncology-related terms

Cancers are classified by the type of cell that the tumor resembles and is therefore presumed to be the origin of the tumor. These types include:

Carcinoma: Cancer derived from epithelial cells. This group includes many of the most common cancers, including those of the breast, prostate, lung and colon.
Sarcoma: Cancer derived from connective tissue, or mesenchymal cells.
Lymphoma and leukemia: Cancer derived from hematopoietic (blood-forming) cells
Germ cell tumor: Cancer derived from pluripotent cells. In adults these are most often found in the testicle and ovary, but are more common in babies and young children.
Blastoma: Cancer derived from immature "precursor" or embryonic tissue. These are also commonest in children.^{[citation needed]}

Cancers are usually named using -carcinoma, -sarcoma or -blastoma as a suffix, with the Latin or Greek word for the organ or tissue of origin as the root. For example, a cancer of the liver is called hepatocarcinoma; a cancer of fat cells is called a liposarcoma. For some common cancers, the English organ name is used. For example, the most common type of breast cancer is called ductal carcinoma of the breast. Here, the adjective ductal refers to the appearance of the cancer under the microscope, which suggests that it has originated in the milk ducts.
Benign tumors (which are not cancers) are named using -oma as a suffix with the organ name as the root. For example, a benign tumor of smooth muscle cells is called a leiomyoma (the common name of this frequently occurring benign tumor in the uterus is fibroid). Confusingly, some types of cancer also use the -oma suffix, examples including melanoma and seminoma.

Signs and symptoms

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Symptoms of cancer metastasis depend on the location of the tumor.

Cancer symptoms can be divided into three groups:

Local symptoms: are restricted to the site of the primary cancer. They can include lumps or swelling (tumor), hemorrhage (bleeding from the skin, mouth or anus), ulceration and pain. Although local pain commonly occurs in advanced cancer, the initial swelling is often painless.
Metastatic symptoms: are due to the spread of cancer to other locations in the body. They can include enlarged lymph nodes (which can be felt or sometimes seen under the skin), hepatomegaly (enlarged liver) or splenomegaly (enlarged spleen) which can be felt in the abdomen, pain or fracture of affected bones, and neurological symptoms.
Systemic symptoms: occur due to distant effects of the cancer that are not related to direct or metastatic spread. Some of these effects can include weight loss (poor appetite and cachexia), fatigue, excessive sweating (especially night sweats), anemia (low red blood cell count) and other specific conditions termed paraneoplastic phenomena. These may be mediated by immunological or hormonal signals from the cancer cells.

None of these are diagnostic, as many of these symptoms commonly occur in patients who do not have cancer.^{[citation needed]}

Causes

Cancers are primarily an environmental disease with 90-95% of cases attributed to environmental factors and 5-10% due to genetics.^[1] Environmental, as used by cancer researchers, means any cause that is not genetic. Common environmental factors that contribute to cancer death include: tobacco (25-30%), diet and obesity (30-35%), infections (15-20%), radiation (both ionizing and non ionizing, up to 10%), stress, lack of physical activity, and environmental pollutants.^[1]

Chemicals

Further information: Alcohol and cancer and Smoking and cancer

The incidence of lung cancer is highly correlated with smoking.^[4]

Cancer pathogenesis is traceable back to DNA mutations that impact cell growth and metastasis. Substances that cause DNA mutations are known as mutagens, and mutagens that cause cancers are known as carcinogens. Particular substances have been linked to specific types of cancer. Tobacco smoking is associated with many forms of cancer,^[5] and causes 90% of lung cancer.^[6]
Many mutagens are also carcinogens, but some carcinogens are not mutagens. Alcohol is an example of a chemical carcinogen that is not a mutagen.^[7] In Western Europe 10% of cancers in males and 3% of cancers in females are attributed to alcohol.^[8]
Decades of research has demonstrated the link between tobacco use and cancer in the lung, larynx, head, neck, stomach, bladder, kidney, esophagus and pancreas.^[9] Tobacco smoke contains over fifty known carcinogens, including nitrosamines and polycyclic aromatic hydrocarbons.^[10] Tobacco is responsible for about one in three of all cancer deaths in the developed world,^[5] and about one in five worldwide.^[10] Lung cancer death rates in the United States have mirrored smoking patterns, with increases in smoking followed by dramatic increases in lung cancer death rates and, more recently,^[when?] decreases in smoking followed by decreases in lung cancer death rates in men. However, the numbers of smokers worldwide is still rising, leading to what some organizations have described as the tobacco epidemic.^[11]
Cancer related to one's occupation is believed to represent between 2–20% of all cases.^[12] Every year, at least 200,000 people die worldwide from cancer related to their workplace.^[13] Currently,^[when?] most cancer deaths caused by occupational risk factors occur in the developed world.^[13] It is estimated that approximately 20,000 cancer deaths and 40,000 new cases of cancer each year in the U.S. are attributable to occupation.^[14] Millions of workers run the risk of developing cancers such as lung cancer and mesothelioma from inhaling asbestos fibers and tobacco smoke, or leukemia from exposure to benzene at their workplaces.^[13]

Diet and exercise

Diet, physical inactivity, and obesity are related to approximately 30–35% of cancer cases.^[1]^[15] In the United States excess body weight is associated with the development of many types of cancer and is a factor in 14–20% of all cancer death.^[15] Physical inactivity is believed to contribute to cancer risk not only through its effect on body weight but also through negative effects on immune system and endocrine system.^[15]
Diets that are low in vegetables, fruits and whole grains, and high in processed or red meats are linked with a number of cancers.^[15] A high salt diet is linked to gastric cancer, aflatoxin B1, a frequent food contaminate, with liver cancer, and Betel nut chewing with oral cancer.^[16] This may partly explain differences in cancer incidence in different countries for example gastric cancer is more common in Japan with its high salt diet^[17] and colon cancer is more common in the United States. Immigrants develop the risk of their new country, often within one generation, suggesting a substantial link between diet and cancer.^[18]

Infection

Main article: Infectious causes of cancer

Worldwide approximately 18% of cancers are related to infectious diseases.^[1] This proportion varies in different regions of the world from a high of 25% in Africa to less than 10% in the developed world.^[1] Viruses are usual infectious agents that cause cancer but bacteria and parasites may also have an effect.
A virus that can cause cancer is called an oncovirus. These include human papillomavirus (cervical carcinoma), Epstein-Barr virus (B-cell lymphoproliferative disease and nasopharyngeal carcinoma), Kaposi's sarcoma herpesvirus (Kaposi's Sarcoma and primary effusion lymphomas), hepatitis B and hepatitis C viruses (hepatocellular carcinoma), and Human T-cell leukemia virus-1 (T-cell leukemias). Bacterial infection may also increase the risk of cancer, as seen in Helicobacter pylori-induced gastric carcinoma.^[19] Parasitic infections strongly associated with cancer include Schistosoma haematobium (squamous cell carcinoma of the bladder) and the liver flukes, Opisthorchis viverrini and Clonorchis sinensis (cholangiocarcinoma).^[20]

Radiation

Up to 10% of invasive cancers are related to radiation exposure, including both ionizing radiation and non-ionizing radiation.^[1] Additionally, the vast majority of non-invasive cancers are non-melanoma skin cancers caused by non-ionizing radiation from ultraviolet radiation.
Sources of ionizing radiation include medical imaging, and radon gas. Radiation can cause cancer in most parts of the body, in all animals, and at any age, although radiation-induced solid tumors usually take 10–15 years, and up to 40 years, to become clinically manifest, and radiation-induced leukemias typically require 2–10 years to appear.^[21] Some people, such as those with nevoid basal cell carcinoma syndrome or retinoblastoma, are more susceptible than average to developing cancer from radiation exposure.^[21] Children and adolescents are twice as likely to develop radiation-induced leukemia as adults; radiation exposure before birth has ten times the effect.^[21] Ionizing radiation is not a particularly strong mutagen.^[21] Residential exposure to radon gas, for example, has similar cancer risks as passive smoking.^[21] Low-dose exposures, such as living near a nuclear power plant, are generally believed to have no or very little effect on cancer development.^[21] Radiation is a more potent source of cancer when it is combined with other cancer-causing agents, such as radon gas exposure plus smoking tobacco.^[21]
Unlike chemical or physical triggers for cancer, ionizing radiation hits molecules within cells randomly. If it happens to strike a chromosome, it can break the chromosome, result in an abnormal number of chromosomes, inactivate one or more genes in the part of the chromosome that it hit, delete parts of the DNA sequence, cause chromosome translocations, or cause other types of chromosome abnormalities.^[21] Major damage normally results in the cell dying, but smaller damage may leave a stable, partly functional cell that may be capable of proliferating and developing into cancer, especially if tumor suppressor genes were damaged by the radiation.^[21] Three independent stages appear to be involved in the creation of cancer with ionizing radiation: morphological changes to the cell, acquiring cellular immortality (losing normal, life-limiting cell regulatory processes), and adaptations that favor formation of a tumor.^[21] Even if the radiation particle does not strike the DNA directly, it triggers responses from cells that indirectly increase the likelihood of mutations.^[21]
Medical use of ionizing radiation is a growing source of radiation-induced cancers. Ionizing radiation may be used to treat other cancers, but this may, in some cases, induce a second form of cancer.^[21] It is also used in some kinds of medical imaging. One report estimates that approximately 29,000 future cancers could be related to the approximately 70 million CT scans performed in the US in 2007.^[22] It is estimated that 0.4% of current^[when?] cancers in the United States are due to CTs performed in the past and that this may increase to as high as 1.5–2% with 2007 rates of CT usage.^[23]
Prolonged exposure to ultraviolet radiation from the sun can lead to melanoma and other skin malignancies.^[24] Clear evidence establishes ultraviolet radiation, especially the non-ionizing medium wave UVB, as the cause of most non-melanoma skin cancers, which are the most common forms of cancer in the world.^[24]
Non-ionizing radio frequency radiation from mobile phones, electric power transmission, and other similar sources have been described as a possible carcinogen by the World Health Organization's International Agency for Research on Cancer.^[25]

Heredity

Main article: Cancer syndrome

The vast majority of cancers are non-hereditary, which are called sporadic cancers. Hereditary cancers are cancers that are primarily caused by an inherited genetic defect. Less than 0.3% of the population are carriers of a genetic mutation which has a large effect on cancer risk.^[26] They cause less than 3–10% of all cancer.^[26] Some of these syndromes include:

certain inherited mutations in the genes BRCA1 and BRCA2 with a more than 75% risk of breast cancer and ovarian cancer^[26]
Li-Fraumeni syndrome (various tumors such as osteosarcoma, breast cancer, soft tissue sarcoma, brain tumors) due to mutations of p53
Turcot syndrome (brain tumors and colonic polyposis)
Familial adenomatous polyposis an inherited mutation of the APC gene that leads to early onset of colon carcinoma.
Hereditary nonpolyposis colorectal cancer (HNPCC, also known as Lynch syndrome) can include familial cases of colon cancer, uterine cancer, gastric cancer, and ovarian cancer, without a preponderance of colon polyps.
Retinoblastoma, when occurring in young children, is due to a hereditary mutation in the retinoblastoma gene.
Down syndrome patients, who have an extra chromosome 21, are known to develop malignancies such as leukemia and testicular cancer, though the reasons for this difference are not well understood.

Physical agents

Some substances cause cancer primarily through their physical, rather than chemical, effects on cells.^[27]
A prominent example of this is prolonged exposure to asbestos, naturally occurring mineral fibers which are a major cause of mesothelioma, a type of lung cancer.^[27] Other substances in this category include both naturally occurring and synthetic asbestos-like fibers, such as wollastonite, attapulgite, glass wool, and rock wool, are believed to have similar effects.^[27]
Nonfibrous particulate materials that cause cancer include powdered metallic cobalt and nickel, and crystalline silica (quartz, cristobalite, and tridymite).^[27]
Usually, physical carcinogens must get inside the body (such as through inhaling tiny pieces) and require years of exposure to develop cancer.^[27]

Physical trauma and inflammation

Physical trauma resulting in cancer is relatively rare.^[28] Claims that breaking bone resulted in bone cancer, for example, have never been proven.^[28] Similarly, physical trauma is not accepted as a cause for cervical cancer, breast cancer, or brain cancer.^[28]
One accepted source is frequent, long-term application of hot objects to the body. It is possible that repeated burns on the same part of the body, such as those produced by kanger and kairo heaters (charcoal hand warmers), may produce skin cancer, especially if carcinogenic chemicals are also present.^[28] Frequently drinking scalding hot tea may produce esophageal cancer.^[28]
Generally, it is believed that the cancer arises, or a pre-existing cancer is encouraged, during the process of repairing the trauma, rather than the cancer being caused directly by the trauma.^[28] However, repeated injuries to the same tissues might promote excessive cell proliferation, which could then increase the odds of a cancerous mutation. There is no evidence that inflammation itself causes cancer.^[28]

Hormones

Some hormones factor in the development of cancer by promoting cell proliferation.^[29] Hormones are important agents in sex-related cancers such as cancer of the breast, endometrium, prostate, ovary, and testis, and also of thyroid cancer and bone cancer.^[29]
An individual's hormone levels are mostly determined genetically, so this may at least partly explains the presence of some cancers that run in families that do not seem to have any cancer-causing genes.^[29] For example, the daughters of women who have breast cancer have significantly higher levels of estrogen and progesterone than the daughters of women without breast cancer. These higher hormone levels may explain why these women have higher risk of breast cancer, even in the absence of a breast-cancer gene.^[29] Similarly, men of African ancestry have significantly higher levels of testosterone than men of European ancestry, and have a correspondingly much higher level of prostate cancer.^[29] Men of Asian ancestry, with the lowest levels of testosterone-activating androstanediol glucuronide, have the lowest levels of prostate cancer.^[29]
However, non-genetic factors are also relevant: obese people have higher levels of some hormones associated with cancer and a higher rate of those cancers.^[29] Women who take hormone replacement therapy have a higher risk of developing cancers associated with those hormones.^[29] On the other hand, people who exercise far more than average have lower levels of these hormones, and lower risk of cancer.^[29] Osteosarcoma may be promoted by growth hormones.^[29] Some treatments and prevention approaches leverage this cause by artificially reducing hormone levels, and thus discouraging hormone-sensitive cancers.^[29]

Other

Excepting the rare transmissions that occur with pregnancies and only a marginal few organ donors, cancer is generally not a transmissible disease. The main reason for this is tissue graft rejection caused by MHC incompatibility.^[30] In humans and other vertebrates, the immune system uses MHC antigens to differentiate between "self" and "non-self" cells because these antigens are different from person to person. When non-self antigens are encountered, the immune system reacts against the appropriate cell. Such reactions may protect against tumour cell engraftment by eliminating implanted cells. In the United States, approximately 3,500 pregnant women have a malignancy annually, and transplacental transmission of acute leukaemia, lymphoma, melanoma and carcinoma from mother to fetus has been observed.^[30] The development of donor-derived tumors from organ transplants is exceedingly rare. The main cause of organ transplant associated tumors seems to be malignant melanoma, that was undetected at the time of organ harvest.^[31] though other cases exist^[32] In fact, cancer from one organism will usually grow in another organism of that species, as long as they share the same histocompatibility genes,^[33] proven using mice; however this would never happen in a real-world setting except as described above.
In non-humans, a few types of transmissible cancer have been described, wherein the cancer spreads between animals by transmission of the tumor cells themselves. This phenomenon is seen in dogs with Sticker's sarcoma, also known as canine transmissible venereal tumor,^[34] as well as devil facial tumour disease in Tasmanian devils.

Pathophysiology

Main articles: Carcinogenesis and The Hallmarks of Cancer

Cancers are caused by a series of mutations. Each mutation alters the behavior of the cell somewhat.

Cancer is fundamentally a disease of failure of regulation of tissue growth. In order for a normal cell to transform into a cancer cell, the genes which regulate cell growth and differentiation must be altered.^[35]
The affected genes are divided into two broad categories. Oncogenes are genes which promote cell growth and reproduction. Tumor suppressor genes are genes which inhibit cell division and survival. Malignant transformation can occur through the formation of novel oncogenes, the inappropriate over-expression of normal oncogenes, or by the under-expression or disabling of tumor suppressor genes. Typically, changes in many genes are required to transform a normal cell into a cancer cell.^[36]
Genetic changes can occur at different levels and by different mechanisms. The gain or loss of an entire chromosome can occur through errors in mitosis. More common are mutations, which are changes in the nucleotide sequence of genomic DNA.
Large-scale mutations involve the deletion or gain of a portion of a chromosome. Genomic amplification occurs when a cell gains many copies (often 20 or more) of a small chromosomal locus, usually containing one or more oncogenes and adjacent genetic material. Translocation occurs when two separate chromosomal regions become abnormally fused, often at a characteristic location. A well-known example of this is the Philadelphia chromosome, or translocation of chromosomes 9 and 22, which occurs in chronic myelogenous leukemia, and results in production of the BCR-abl fusion protein, an oncogenic tyrosine kinase.
Small-scale mutations include point mutations, deletions, and insertions, which may occur in the promoter region of a gene and affect its expression, or may occur in the gene's coding sequence and alter the function or stability of its protein product. Disruption of a single gene may also result from integration of genomic material from a DNA virus or retrovirus, and resulting in the expression of viral oncogenes in the affected cell and its descendants.
Replication of the enormous amount of data contained within the DNA of living cells will probabilistically result in some errors (mutations). Complex error correction and prevention is built into the process, and safeguards the cell against cancer. If significant error occurs, the damaged cell can "self destruct" through programmed cell death, termed apoptosis. If the error control processes fail, then the mutations will survive and be passed along to daughter cells.
Some environments make errors more likely to arise and propagate. Such environments can include the presence of disruptive substances called carcinogens, repeated physical injury, heat, ionising radiation, or hypoxia^[37] (see causes, below).
The errors which cause cancer are self-amplifying and compounding, for example:

A mutation in the error-correcting machinery of a cell might cause that cell and its children to accumulate errors more rapidly
A further mutation in an oncogene might cause the cell to reproduce more rapidly and more frequently than its normal counterparts.
A further mutation may cause loss of a tumour suppressor gene, disrupting the apoptosis signalling pathway and resulting in the cell becoming immortal.
A further mutation in signaling machinery of the cell might send error-causing signals to nearby cells.

The transformation of normal cell into cancer is akin to a chain reaction caused by initial errors, which compound into more severe errors, each progressively allowing the cell to escape the controls that limit normal tissue growth. This rebellion-like scenario becomes an undesirable survival of the fittest, where the driving forces of evolution work against the body's design and enforcement of order. Once cancer has begun to develop, this ongoing process, termed clonal evolution drives progression towards more invasive stages.^[38]

Diagnosis

Chest x-ray showing lung cancer in the left lung.

Most cancers are initially recognized either because signs or symptoms appear or through screening. Neither of these lead to a definitive diagnosis, which usually requires the opinion of a pathologist, a type of physician (medical doctor) who specializes in the diagnosis of cancer and other diseases. People with suspected cancer are investigated with medical tests. These commonly include blood tests, X-rays, CT scans and endoscopy.

Pathology

A cancer may be suspected for a variety of reasons, but the definitive diagnosis of most malignancies must be confirmed by histological examination of the cancerous cells by a pathologist. Tissue can be obtained from a biopsy or surgery. Many biopsies (such as those of the skin, breast or liver) can be done in a doctor's office. Biopsies of other organs are performed under anesthesia and require surgery in an operating room.
The tissue diagnosis given by the pathologist indicates the type of cell that is proliferating, its histological grade, genetic abnormalities, and other features of the tumor. Together, this information is useful to evaluate the prognosis of the patient and to choose the best treatment. Cytogenetics and immunohistochemistry are other types of testing that the pathologist may perform on the tissue specimen. These tests may provide information about the molecular changes (such as mutations, fusion genes, and numerical chromosome changes) that has happened in the cancer cells, and may thus also indicate the future behavior of the cancer (prognosis) and best treatment.

An invasive ductal carcinoma of the breast (pale area at the center) surrounded by spikes of whitish scar tissue in the surrounding yellow fatty tissue.
An invasive colorectal carcinoma (top center) in a colectomy specimen.
A squamous cell carcinoma (the whitish tumor) near the bronchi in a lung specimen.
A large invasive ductal carcinoma in a mastectomy specimen.

Prevention

Cancer prevention is defined as active measures to decrease the incidence of cancer.^[39] The vast majority of cancer risk factors are environmental or lifestyle-related, thus cancer is largely a preventable disease.^[40] Greater than 30% of cancer is preventable via avoiding risk factors including: tobacco, overweight or obesity, low fruit and vegetable intake, physical inactivity, alcohol, sexually transmitted infections, and air pollution.^[41]

Dietary

Main article: Diet and cancer

Dietary recommendations to reduce the risk of developing cancer, including: (1) reducing intake of foods and drinks that promote weight gain, namely energy-dense foods and sugary drinks, (2) eating mostly foods of plant origin, (3) limiting intake of red meat and avoiding processed meat, (4) limiting consumption of alcoholic beverages, and (5) reducing intake of salt and avoiding mouldy cereals (grains) or pulses (legumes).^[42]^[43]
Proposed dietary interventions for cancer risk reduction generally gain support from epidemiological association studies. Examples of such studies include reports that reduced meat consumption is associated with decreased risk of colon cancer,^[44] and reports that consumption of coffee is associated with a reduced risk of liver cancer.^[45] Studies have linked consumption of grilled meat to an increased risk of stomach cancer,^[46] colon cancer,^[47] breast cancer,^[48] and pancreatic cancer,^[49] a phenomenon which could be due to the presence of carcinogens in foods cooked at high temperatures.^[50] Whether reducing obesity in a population also reduces cancer incidence is unknown. Some studies have found that consuming lots of fruits and vegetables has little if any effect on preventing cancer.^[51] A 2005 secondary prevention study showed that consumption of a plant-based diet and lifestyle changes resulted in a reduction in cancer markers in a group of men with prostate cancer who were using no conventional treatments at the time.^[52] These results were amplified by a 2006 study. Over 2,400 women were studied, half randomly assigned to a normal diet, the other half assigned to a diet containing less than 20% calories from fat. The women on the low fat diet were found to have a markedly lower risk of breast cancer recurrence, in the interim report of December, 2006.^[53]

Medication

The concept that medications could be used to prevent cancer is an attractive one, and many high-quality clinical trials support the use of such chemoprevention in defined circumstances. Aspirin has been found to reduce the risk of death from cancer.^[54] Daily use of tamoxifen or raloxifene has been demonstrated to reduce the risk of developing breast cancer in high-risk women by about 50%.^[55]Finasteride has been shown to lower the risk of prostate cancer, though it seems to mostly prevent low-grade tumors.^[56] The effect of COX-2 inhibitors such as rofecoxib and celecoxib upon the risk of colon polyps have been studied in familial adenomatous polyposis patients^[57] and in the general population.^[58]^[59] In both groups, there were significant reductions in colon polyp incidence, but this came at the price of increased cardiovascular toxicity.
Vitamins have not been found to be effective at preventing cancer,^[60] although low levels of vitamin D are correlated with increased cancer risk.^[61]^[62] Whether this relationship is causal and vitamin D supplementation is protective is yet to be determined.^[63] Beta-carotene supplementation has been found to increase slightly, but not significantly, risks of lung cancer.^[64] Folic acid supplementation has not been found effective in preventing colon cancer and may increase colon polyps.^[65]

Vaccination

Vaccines have been developed that prevent some infection by some viruses that are associated with cancer, and therapeutic vaccines are in development^[when?] to stimulate an immune response against cancer-specific epitopes.^[66] Human papillomavirus vaccine (Gardasil and Cervarix) decreases the risk of developing cervical cancer.^[66] The hepatitis B vaccine prevents infection with hepatitis B virus and thus decreases the risk of liver cancer.^[66]
Advances in cancer research have made a vaccine designed to prevent cancers available. In 2006, the U.S. Food and Drug Administration (FDA) approved a human papilloma virus vaccine, called Gardasil. The vaccine protects against 6,11,16,18 strains of HPV, which together cause 70% of cervical cancers and 90% of genital warts. It also lists vaginal and vulvar cancers as being protected. In March 2007, the US Centers for Disease Control and Prevention (CDC) Advisory Committee on Immunization Practices (ACIP) officially recommended that females aged 11–12 receive the vaccine, and indicated that females as young as age 9 and as old as age 26 are also candidates for immunization. There is a second vaccine from Cervarix which protects against the more dangerous HPV 16,18 strains only. In 2009, Gardasil was approved for protection against genital warts. In 2010, the Gardasil vaccine was approved for protection against anal cancer for males and reviewers stated there was no anatomical, histological or physiological anal differences between the genders so females would also be protected.

Screening

Main article: Cancer screening

Unlike diagnosis efforts prompted by symptoms and medical signs, cancer screening involves efforts to detect cancer after it has formed, but before any noticeable symptoms appear.^[67] This may involve physical examination, blood or urine tests, or medical imaging.^[67]
Cancer screening is not currently^[when?] possible for some types of cancers, and even when tests are available, they are not recommended to everyone. Universal screening or mass screening involves screening everyone.^[68] Selective screening identifies people who are known to be at higher risk of developing cancer, such as people with a family history of cancer.^[68]
Several factors are considered to determine whether the benefits of screening outweigh the risks and the costs of screening.^[67] These factors include:

Possible harms from the screening test: Some types of screening tests, such as X-ray images, expose the body to potentially harmful ionizing radiation. There is a small chance that the radiation in the test could cause a new cancer in a healthy person. Screening mammography, used to detect breast cancer, is not recommended to men or to young women because they are more likely to be harmed by the test than to benefit from it. Other tests, such as a skin check for skin cancer, have no significant risk of harm to the patient. A test that has high potential harms is only recommended when the benefits are also high.
The likelihood of the test correctly identifying cancer: If the test is not sensitive, then it may miss cancers. If the test is not specific, then it may wrongly indicate cancer in a healthy person. All cancer screening tests produce both false positives and false negatives, and most produce more false positives. Experts consider the rate of errors when making recommendations about which test, if any, to use. A test may work better in some populations than others. The positive predictive value is a calculation of the likelihood that a positive test result actually represents cancer in a given individual, based on the results of people with similar risk factors.
The likelihood of cancer being present: Screening is not normally useful for rare cancers. It is rarely done for young people, since cancer is largely a disease found in people over the age of 50. Countries often focus their screening recommendations on the major forms of treatable cancer found in their population. For example, the United States recommends universal screening for colon cancer, which is common in the US, but not for stomach cancer, which is less common; by contrast, Japan recommends screening for stomach cancer, but not colon cancer, which is rarer in Japan. Screening recommendations depend on the individual's risk, with high-risk people receiving earlier and more frequent screening than low-risk people.
Possible harms from follow-up procedures: If the screening test is positive, further diagnostic testing is normally done, such as a biopsy of the tissue. If the test produces many false positives, then many people will undergo needless medical procedures, some of which may be dangerous.
Whether suitable treatment is available and appropriate: Screening is discouraged if no effective treatment is available.^[68] When effective and suitable treatment is not available, then diagnosis of a fatal disease produces significant mental and emotional harms. For example, routine screening for cancer is typically not appropriate in a very frail elderly person, because the treatment for any cancer that is detected might kill the patient.
Whether early detection improves treatment outcomes: Even when treatment is available, sometimes early detection does not improve the outcome. If the treatment result is the same as if the screening had not been done, then the only screening program does is increase the length of time the person lived with the knowledge that he had cancer. This phenomenon is called lead-time bias. A useful screening program reduces the number of years of potential life lost (longer lives) and disability-adjusted life years lost (longer healthy lives).
Whether the cancer will ever need treatment: Diagnosis of a cancer in a person who will never be harmed by the cancer is called overdiagnosis. Overdiagnosis is most common among older people with slow-growing cancers. Concerns about overdiagnosis are common for breast and prostate cancer.
Whether the test is acceptable to the patients:If a screening test is too burdensome, such as requiring too much time, too much pain, or culturally unacceptable behaviors, then people will refuse to participate.^[68]
Cost of the test: Some expert bodies, such as the U.S. Preventive Services Task Force, completely ignore the question of money. Most, however, include a cost-effectiveness analysis that, all else being equal, favors less expensive tests over more expensive tests, and attempt to balance the cost of the screening program against the benefits of using those funds for other health programs. These analyses usually include the total cost of the screening program to the healthcare system, such as ordering the test, performing the test, reporting the results, and biopsies for suspicious results, but not usually the costs to the individual, such as for time taken away from employment.

Recommendations

The U.S. Preventive Services Task Force (USPSTF) strongly recommends cervical cancer screening in women who are sexually active and have a cervix at least until the age of 65.^[69] They recommend that Americans be screened for colorectal cancer via fecal occult blood testing, sigmoidoscopy, or colonoscopy starting at age 50 until age 75.^[70] There is insufficient evidence to recommend for or against screening for skin cancer,^[71] oral cancer,^[72] lung cancer,^[73] or prostate cancer in men under 75.^[74] Routine screening is not recommended for bladder cancer,^[75] testicular cancer,^[76] ovarian cancer,^[77] pancreatic cancer,^[78] or prostate cancer in men over 75.^[74]
The USPSTF recommends mammography for breast cancer screening every two years for those 50–74 years old; however, they do not recommend either breast self-examination or clinical breast examination.^[79] A 2009 Cochrane review came to slightly different conclusions with respect to breast cancer screening stating that routine mammography may do more harm than good.^[80]
Japan screens for gastric cancer using photofluorography due to the high incidence there.^[3]

Genetic testing

Gene	Cancer types
BRCA1, BRCA2	Breast, ovarian, pancreatic
HNPCC, MLH1, MSH2, MSH6, PMS1, PMS2	Colon, uterine, small bowel, stomach, urinary tract

Management

Main article: Management of cancer

Many management options for cancer exist including: chemotherapy, radiation therapy, surgery, immunotherapy, monoclonal antibody therapy and other methods. Which treatments are used depends upon the type of cancer, the location and grade of the tumor, and the stage of the disease, as well as the general state of a person's health.
Complete removal of the cancer without damage to the rest of the body is the goal of treatment for most cancers. Sometimes this can be accomplished by surgery, but the propensity of cancers to invade adjacent tissue or to spread to distant sites by microscopic metastasis often limits its effectiveness. Surgery often required the removal of a wide surgical margin or a free margin. The width of the free margin depends on the type of the cancer, the method of removal (CCPDMA, Mohs surgery, POMA, etc.). The margin can be as little as 1 mm for basal cell cancer using CCPDMA or Mohs surgery, to several centimeters for aggressive cancers. The effectiveness of chemotherapy is often limited by toxicity to other tissues in the body. Radiation can also cause damage to normal tissue.
Because cancer is a class of diseases,^[82]^[83] it is unlikely that there will ever be a single "cure for cancer" any more than there will be a single treatment for all infectious diseases.^[84] Angiogenesis inhibitors were once thought to have potential as a "silver bullet" treatment applicable to many types of cancer, but this has not been the case in practice.^[85]
Experimental cancer treatments are treatments that are being studied to see whether they work. Typically, these are studied in clinical trials to compare the proposed treatment to the best existing treatment. They may be entirely new treatments, or they may be treatments that have been used successfully in one type of cancer, and are now being tested to see whether they are effective in another type.^[86] More and more, such treatments are being developed alongside companion diagnostic tests to target the right drugs to the right patients, based on their individual biology.^[87]

Alternative treatments

Alternative cancer treatments are treatments used by alternative medicine practitioners. These are a group of non-related interventions that do not fit the rigors of Western medicine and include mind–body interventions, herbal preparations, massage, acupuncture, reiki, electrical stimulation devices, and a variety of strict dietary regimens among others.
Alternative cancer treatments have never been shown to be effective at killing cancer cells in research studies, but remain popular in some cultures and religions. Some are dangerous, but most are harmless or provide the patient with a degree of physical or emotional comfort. Alternative cancer treatment has also been a fertile field for hoaxes aimed at stripping desperate patients of their money.^[88]
Many physicians are supportive of patients using alternative medicine in addition to standard management, especially for symptom management, though certain types of alternative herbs or diets could actually interfere with treatments and should be discussed with an oncologist if undergoing chemotherapy or radiation treatments.^[89]^[90]^[91]^[92]

Palliative care

Palliative care is a multidisciplinary approach to symptom management that aims to reduce the physical, emotional, spiritual, and psycho-social distress experienced by people with cancer. Unlike treatment that is aimed at directly killing cancer cells, the primary goal of palliative care is to make the person feel better as soon as possible.
Palliative care is often confused with hospice and therefore only involved when patients approach end of life. Like hospice care, palliative care attempts to help the person cope with the immediate needs and to increase the person's comfort. Unlike hospice care, palliative care does not require patients to stop treatment aimed at prolonging their lives or curing the cancer.
Multiple national medical guidelines recommend early palliative care involvement in people whose cancer has produced complex symptoms (pain, shortness of breath, fatigue, nausea) or who need help coping with their illness. In people who have metastatic disease when first diagnosed, oncologists should consider a palliative care consult immediately. Additionally, an oncologist should consider a palliative care consult in any patient they feel has a prognosis of less than 12 months even if continuing aggressive treatment.^[93]^[94]^[95]

Prognosis

Epidemiology

Main article: Epidemiology of cancer

Death rate from malignant cancer per 100,000 inhabitants in 2004.^[99]

no data

≤ 55

55-80

80-105

105-130

130-155

155-180

180-205

205-230

230-255

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≥ 305

In 2008 approximately 12.7 million cancers were diagnosed (excluding non-melanoma skin cancers and other non-invasive cancers) and 7.6 million people died of cancer worldwide.^[3] Cancers as a group account for approximately 13% of all deaths each year with the most common being: lung cancer (1.3 million deaths), stomach cancer (803,000 deaths), colorectal cancer (639,000 deaths), liver cancer (610,000 deaths), and breast cancer (519,000 deaths).^[100] This makes invasive cancer the leading cause of death in the developed world and the second leading cause of death in the developing world.^[3] Over half of cases occur in the developing world.^[3]
Global cancer rates have been increasing primarily due to an aging population and lifestyle changes in the developing world.^[3] The most significant risk factor for developing cancer is old age.^[101] Although it is possible for cancer to strike at any age, most people who are diagnosed with invasive cancer are over the age of 65.^[101] According to cancer researcher Robert A. Weinberg, "If we lived long enough, sooner or later we all would get cancer."^[102] Some of the association between aging and cancer is attributed to immunosenescence,^[103] errors accumulated in DNA over a lifetime, and age-related changes in the endocrine system.^[104]
Some slow-growing cancers are particularly common. Autopsy studies in Europe and Asia have shown that up to 36% of people have undiagnosed and apparently harmless thyroid cancer at the time of their deaths, and that 80% of men develop prostate cancer by age 80.^[105]^[106] As these cancers, often very small, did not cause the person's death, identifying them would have represented overdiagnosis rather than useful medical care.
The three most common childhood cancers are leukemia (34%), brain tumors (23%), and lymphomas (12%).^[107] Rates of childhood cancer have increased between 0.6% per year between 1975 to 2002 in the United States^[108] and by 1.1% per year between 1978 and 1997 in Europe.^[107]

History

Hippocrates (ca. 460 BC – ca. 370 BC) described several kinds of cancers, referring to them with the Greek word carcinos (crab or crayfish), among others.^[109] This name comes from the appearance of the cut surface of a solid malignant tumour, with "the veins stretched on all sides as the animal the crab has its feet, whence it derives its name".^[110] Since it was against Greek tradition to open the body, Hippocrates only described and made drawings of outwardly visible tumors on the skin, nose, and breasts. Treatment was based on the humor theory of four bodily fluids (black and yellow bile, blood, and phlegm). According to the patient's humor, treatment consisted of diet, blood-letting, and/or laxatives. Through the centuries it was discovered that cancer could occur anywhere in the body, but humor-theory based treatment remained popular until the 19th century with the discovery of cells.

Engraving with two views of a Dutch woman who had a tumor removed from her neck in 1689.

Celsus (ca. 25 BC - 50 AD) translated carcinos into the Latin cancer, also meaning crab. Galen (2nd century AD) called benign tumours oncos, Greek for swelling, reserving Hippocrates' carcinos for malignant tumours. He later added the suffix -oma, Greek for swelling, giving the name carcinoma.
The oldest known description and surgical treatment of cancer was discovered in Egypt and dates back to approximately 1600 BC. The Papyrus describes 8 cases of ulcers of the breast that were treated by cauterization, with a tool called "the fire drill." The writing says about the disease, "There is no treatment."^[111]
In the 16th and 17th centuries, it became more acceptable for doctors to dissect bodies to discover the cause of death. The German professor Wilhelm Fabry believed that breast cancer was caused by a milk clot in a mammary duct. The Dutch professor Francois de la Boe Sylvius, a follower of Descartes, believed that all disease was the outcome of chemical processes, and that acidic lymph fluid was the cause of cancer. His contemporary Nicolaes Tulp believed that cancer was a poison that slowly spreads, and concluded that it was contagious.^[112]
The first cause of cancer was identified by British surgeon Percivall Pott, who discovered in 1775 that cancer of the scrotum was a common disease among chimney sweeps. The work of other individual physicians led to various insights, but when physicians started working together they could make firmer conclusions.
With the widespread use of the microscope in the 18th century, it was discovered that the 'cancer poison' spread from the primary tumor through the lymph nodes to other sites ("metastasis"). This view of the disease was first formulated by the English surgeon Campbell De Morgan between 1871 and 1874.^[113] The use of surgery to treat cancer had poor results due to problems with hygiene. The renowned Scottish surgeon Alexander Monro saw only 2 breast tumor patients out of 60 surviving surgery for two years. In the 19th century, asepsis improved surgical hygiene and as the survival statistics went up, surgical removal of the tumor became the primary treatment for cancer. With the exception of William Coley who in the late 19th century felt that the rate of cure after surgery had been higher before asepsis (and who injected bacteria into tumors with mixed results), cancer treatment became dependent on the individual art of the surgeon at removing a tumor. During the same period, the idea that the body was made up of various tissues, that in turn were made up of millions of cells, laid rest the humor-theories about chemical imbalances in the body. The age of cellular pathology was born.
The genetic basis of cancer was recognised in 1902 by the German zoologist Theodor Boveri, professor of zoology at Munich and later in Würzburg.^[114] He discovered a method to generate cells with multiple copies of the centrosome, a structure he discovered and named. He postulated that chromosomes were distinct and transmitted different inheritance factors. He suggested that mutations of the chromosomes could generate a cell with unlimited growth potential which could be passed onto its descendants. He proposed the existence of cell cycle check points, tumour suppressor genes and oncogenes. He speculated that cancers might be caused or promoted by radiation, physical or chemical insults or by pathogenic microorganisms.

1938 poster identifying surgery, x-rays and radium as the proper treatments for cancer.

When Marie Curie and Pierre Curie discovered radiation at the end of the 19th century, they stumbled upon the first effective non-surgical cancer treatment. With radiation also came the first signs of multi-disciplinary approaches to cancer treatment. The surgeon was no longer operating in isolation, but worked together with hospital radiologists to help patients. The complications in communication this brought, along with the necessity of the patient's treatment in a hospital facility rather than at home, also created a parallel process of compiling patient data into hospital files, which in turn led to the first statistical patient studies.
A founding paper of cancer epidemiology was the work of Janet Lane-Claypon, who published a comparative study in 1926 of 500 breast cancer cases and 500 control patients of the same background and lifestyle for the British Ministry of Health. Her ground-breaking work on cancer epidemiology was carried on by Richard Doll and Austin Bradford Hill, who published "Lung Cancer and Other Causes of Death In Relation to Smoking. A Second Report on the Mortality of British Doctors" followed in 1956 (otherwise known as the British doctors study). Richard Doll left the London Medical Research Center (MRC), to start the Oxford unit for Cancer epidemiology in 1968. With the use of computers, the unit was the first to compile large amounts of cancer data. Modern epidemiological methods are closely linked to current^[when?] concepts of disease and public health policy. Over the past 50 years, great efforts have been spent on gathering data across medical practise, hospital, provincial, state, and even country boundaries to study the interdependence of environmental and cultural factors on cancer incidence.
Cancer patient treatment and studies were restricted to individual physicians' practices until World War II, when medical research centers discovered that there were large international differences in disease incidence. This insight drove national public health bodies to make it possible to compile health data across practises and hospitals, a process that many countries do today. The Japanese medical community observed that the bone marrow of victims of the atomic bombings of Hiroshima and Nagasaki was completely destroyed. They concluded that diseased bone marrow could also be destroyed with radiation, and this led to the discovery of bone marrow transplants for leukemia. Since World War II, trends in cancer treatment are to improve on a micro-level the existing treatment methods, standardize them, and globalize them to find cures through epidemiology and international partnerships.

Society and culture

While many diseases (such as heart failure) may have a worse prognosis than most cases of cancer, it is the subject of widespread fear and taboos. Euphemisms, once "a long illness", and now informally as "the big C", provide distance and soothe superstitions.^[115] This deep belief that cancer is necessarily a difficult and usually deadly disease is reflected in the systems chosen by society to compile cancer statistics: the most common form of cancer—non-melanoma skin cancers, accounting for about one-third of all cancer cases worldwide, but very few deaths^[116]^[117]—are excluded from cancer statistics specifically because they are easily treated and almost always cured, often in a single, short, outpatient procedure.^[118]
Cancer is regarded as a disease that must be "fought" to end the "civil insurrection"; a War on Cancer has been declared. Military metaphors are particularly common in descriptions of cancer's human effects, and they emphasize both the parlous state of the affected individual's health and the need for the individual to take immediate, decisive actions himself, rather than to delay, to ignore, or to rely entirely on others caring for him. The military metaphors also help rationalize radical, destructive treatments.^[119]^[120]
In the 1970s, a relatively popular alternative cancer treatment was a specialized form of talk therapy, based on the idea that cancer was caused by a bad attitude.^[88] People with a "cancer personality"—depressed, repressed, self-loathing, and afraid to express their emotions—were believed to have manifested cancer through subconscious desire. Some psychotherapists said that treatment to change the patient's outlook on life would cure the cancer.^[88] Among other effects, this belief allows society to blame the victim for having caused the cancer (by "wanting" it) or having prevented its cure (by not becoming a sufficiently happy, fearless, and loving person).^[121] It also increases patients' anxiety, as they incorrectly believe that natural emotions of sadness, anger or fear shorten their lives.^[121] The idea was excoriated by the notoriously outspoken Susan Sontag, who published Illness as Metaphor while recovering from treatment for breast cancer in 1978.^[88] Although the original idea is now generally regarded as nonsense, the idea partly persists in a reduced form with a widespread, but incorrect, belief that deliberately cultivating a habit of positive thinking will increase survival.^[121] This notion is particularly strong in breast cancer culture.^[121]

Research

Main article: Cancer research

Cancer research is the intense scientific effort to understand disease processes and discover possible therapies.
Research about cancer causes focusses on the following issues:

Agents (e.g. viruses) and events (e.g. mutations) which cause or facilitate genetic changes in cells destined to become cancer.
The precise nature of the genetic damage, and the genes which are affected by it.
The consequences of those genetic changes on the biology of the cell, both in generating the defining properties of a cancer cell, and in facilitating additional genetic events which lead to further progression of the cancer.

The improved understanding of molecular biology and cellular biology due to cancer research has led to a number of new, effective treatments for cancer since President Nixon declared "War on Cancer" in 1971. Since 1971 the United States has invested over $200 billion on cancer research; that total includes money invested by public and private sectors and foundations.^[122] Despite this substantial investment, the country has seen a five percent decrease in the cancer death rate (adjusting for size and age of the population) between 1950 and 2005.^[123]
Leading cancer research organizations and projects include the American Association for Cancer Research, the American Cancer Society (ACS), the American Society of Clinical Oncology, the European Organisation for Research and Treatment of Cancer, ECCO - the European Cancer Organisation, the National Cancer Institute, the National Comprehensive Cancer Network, and The Cancer Genome Atlas project at the NCI.

Cancer and Treatment Tips

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Training

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Anti Aging

Cancer Treatment Tips

Contents

Classification

Signs and symptoms

Causes

Chemicals

Diet and exercise

Infection

Radiation

Heredity

Physical agents

Physical trauma and inflammation

Hormones

Other

Pathophysiology

Diagnosis

Pathology

Prevention

Dietary

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Screening

Recommendations

Genetic testing

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Prognosis

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