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Prevention and Treatment of Cancers Research Projects:
Endometrial Cancer Biomedical Societies and Associations |
There are more than 200 different types of human cancers. Cancer affects people at all ages with the risk for most types increasing with age. Worldwide there are 24.6 million people alive who have received a diagnosis of cancer in the last five years. It is estimated that there will be more than 12 million new cancer cases worldwide, of which 5.4 million will occur in economically developed countries and 6.7 million in economically developing countries. The corresponding estimates for total cancer deaths are 7.6 million (about 20,000 cancer deaths a day), 2.9 million in economically developed countries and 4.7 million in economically developing countries. By 2050, the global burden is expected to grow to 27 million new cancer cases and 17.5 million cancer deaths simply due to the growth and aging of the population.Worldwide cancer caused 13% of all deaths (7-8 million), only second to heart diseases. The leading cancer death causes were: lung cancer (1.3 million deaths/year), stomach cancer (803,000 deaths), colorectal cancer (639,000 deaths), liver cancer (610,000 deaths), and breast cancer (519,000 deaths). In the United States, cancer is responsible for 25% of all deaths with 30% of these from lung cancer. The most commonly occurring cancer in men is prostate cancer (about 25% of new cases) and in women is breast cancer (also about 25%). Cancer can occur in children and adolescents, but it is uncommon (about 150 cases per million in the U.S.), with leukemia the most common. In the first year of life the incidence is about 230 cases per million in the U.S., with the most common being neuroblastoma.
In the developed world, one in three people will develop cancer during their lifetimes. If all cancer patients survived and cancer occurred randomly, the lifetime odds of developing an second primary cancer would be one in nine. However, cancer survivors have an increased risk of developing a second primary cancer, and the odds are about two in nine. About half of these second primaries can be attributed to the normal one-in-nine risk associated with random chance. The increased risk is believed to be primarily due to the same risk factors that produced the first cancer, such as the person's genetic profile, alcohol and tobacco use, obesity, and environmental exposures, and partly due, to the treatment for the first cancer, which typically includes mutagenic chemotherapeutic drugs or radiation. Cancer survivors may also be more likely to comply with recommended screening, and thus may be more likely than average to detect cancers.
Cancer is caused by both external factors (tobacco, infectious organisms, chemicals, and radiation) and internal factors (inherited mutations, hormones, immune conditions, and mutations that occur from metabolism). These causal factors may act together or in sequence to initiate or promote carcinogenesis. Chemical Carcinogens: 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, and causes 90% of lung cancer. Prolonged exposure to asbestos fibers is associated with mesothelioma. Decades of research has demonstrated the link between tobacco use and cancer in the lung, larynx, head, neck, stomach, bladder, kidney, oesophagus and pancreas. Tobacco smoke contains over fifty known carcinogens, including nitrosamines and polycyclic aromatic hydrocarbons.Tobacco is responsible for about one in three of all cancer deaths in the developed world, and about one in five worldwide. Ionizing Radiation: Sources of ionizing radiation, such as radon gas, can cause cancer. Prolonged exposure to ultraviolet radiation from the sun can lead to melanoma and other skin malignancies.It is estimated that 2% of future cancers will be due to current CT scans. Non-ionizing radio frequency radiation from mobile phones and other similar RF sources has also been proposed as a cause of cancer, but there is currently little established evidence of such a link. Infection: Some cancers can be caused by infection. This is especially true in animals such as birds, but also in humans, with viruses responsible for up to 20% of human cancers worldwide. These include human papillomavirus (cervical carcinoma), human polyomaviruses (mesothelioma, brain tumors), 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), Human T-cell leukemia virus-1 (T-cell leukemias), and Helicobacter pylori (gastric carcinoma). Hormonal imbalance: Some hormones can act in a similar manner to non-mutagenic carcinogens in that they may stimulate excessive cell growth. Immune system dysfunction: HIV is associated with a number of malignancies, including Kaposi's sarcoma, non-Hodgkin's lymphoma, and HPV-associated malignancies such as anal cancer and cervical cancer. AIDS-defining illnesses have long included these diagnoses. The increased incidence of malignancies in HIV patients points to the breakdown of immune surveillance as a possible etiology of cancer. Certain other immune deficiency states (e.g. common variable immunodeficiency and IgA deficiency) are also associated with increased risk of malignancy. Heredity: Most forms of cancer are sporadic, meaning that there is no inherited cause of the cancer. There are, however, a number of recognised syndromes where there is an inherited predisposition to cancer, often due to a defect in a gene that protects against tumor formation. Famous examples are:
Cancer is treated with surgery, radiation, chemotherapy, hormone therapy, biological therapy( immunotherapy, monoclonal antibody therapy ), and targeted therapy. Which are used depends upon the location and grade of the tumor and the stage of the disease, as well as the general state of a person's health. Experimental cancer treatments are also under development. Currently, the following chemical drugs are using to treat some types of cancer. * Gleevec(imatinib): It has been used to treat certain types of leukemia and other cancers of the blood cells. * Iressa (gefitinib): It can be used to treat non-small cell lung cancer. * Tarceva (erlotinib): It can be used as a replacement for Iressa for treatment of non-small cell lung cancer if Iressa does not work. Tarceva plus Gemzar (gemcitabine) is also used to treat pancreatic cancer. * Sutent (sunitinib): It is used to treat gastrointestinal stromal tumors and tumors associated with esophagus. it is also used for treating advanced renal cell carcinoma. * Nexavar (sorafenib): It can be used to treat advanced renal cell carcinoma, primary liver cancer. * Votrient (pazopanib): A drug that are used to treat renal cell carcinoma, ovarian cancer, soft tissue sarcoma, and non-small cell lung cancer.
Cancer prevention is defined as active measures to decrease the incidence of cancer. 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 infection, air pollution. This can be accomplished by avoiding carcinogens or altering their metabolism, pursuing a lifestyle or diet that modifies cancer-causing factors and/or medical intervention (chemoprevention, treatment of pre-malignant lesions). The epidemiological concept of "prevention" is usually defined as either primary prevention, for people who have not been diagnosed with a particular disease, or secondary prevention, aimed at reducing recurrence or complications of a previously diagnosed illness.
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