Cancer

The term cancer refers to many different diseases. They all have in common uncontrolled cell proliferation (growth and division). Cancers are usually named for the organ or cell type that is originally involved. After beginning at one site, cancer may metastasize (spread) to other organs. The cancer is still named by its place of origin. "All known cancer-inducing agents — certain chemicals and viruses and ionizing radiation — act by breaking chemical bonds to produce DNA mutations." [1]

Types of Cancer

X-Ray of patient with tumor cancer in right lung

Lung tumor

Data are for USA

Most common cancers in men:

Deadliest cancers in men:

Lung
Prostate
Colon
Pancreatic
Leukemia
Liver
Stomach

Most common cancers in women

Breast
Lung
Colorectal

Deadliest cancers in women

Lung
Breast
Colorectal
Pancreatic
Uterus
Stomach

see Mortality

Prevention and Screening

Preventative strategies are continuously being revised. Please see references below for up to date information.

Breast cancer: In women without a family history of breast cancer, mammograms should be done yearly. Clinical breast exam by a medical professional should also be done yearly. Women who have had abortions are significantly more likely to contract breast cancer.
Lung cancer: There are no currently accepted preventative guidelines
Prostate cancer: evidence is inconclusive, but most doctors recommend yearly PSA blood test and digital rectal exam
Colon cancer: in people without a family history of colon cancer, most sources recommend a colonoscopy at age 50, with further studies based on the results. Fecal occult blood testing should also be conducted yearly.
Cervical cancer: yearly Pap smears should be done on all women who have been sexually active and have not had a hysterectomy. Over age 65, women in monogamous relationships and recent normal Pap smears probably do not need to be screened as frequently.
Testicular cancer: the evidence is unclear, however most physicians recommend routine testicular exams in young men.
Skin cancer: keep skin protected from sunlight by use of clothing and sunscreen, and watch you skin for new moles, or changes in existing moles.

Treatment of cancer

Chemotherapy

Chemotherapy is the use of drugs that kill tumor cells. Conventionally, the drugs that are used are those that target cells which are rapidly undergoing mitosis; this approach is effective but is limited by side effects, which occur because these drugs have an adverse effect on normal tissues that contain rapidly-dividing cells. Research is under way to find drugs with a wider therapeutic index. One approach is to study specific molecular markers that may be used to identify cancer cells, and to develop drugs that preferentially kill cells that exhibit those markers.

Radiation therapy

Radiation therapy involves the use of precisely-targeted radiation to destroy cancer cells. Because radiation damages DNA and thus has the ability both to treat and to cause cancer, this method of treatment must be administered by physicians highly-skilled in physics.

Surgery

The goal of cancer surgery is to physically remove the abnormal cells. This becomes more difficult after the cancer spreads. Often, chemotherapy is used either before or after surgery to kill cancer cells that have metastasized.

Immunotherapy

The immune system contains a number of cell types, such as NK cells and killer T cells that have the capability to destroy other cells that have become infected with viruses or have become cancerous. Immunotherapy involves the enhancement or potentiation of these natural defenses against tumor cells. A common procedure is to remove immature immune cells from the patient's bone marrow, purify the T-cells and expose them to antigens from the tumor. The activated cells are then re-injected, allowing them to seek out cancerous tissues.

Dichloroacetate

Dichloroacetate (DCA) is a chemical with the formula: CHCl₂COOH. DCA cures cancer by restoring the mitochondria of cancer cells. Cancer cells use glycolysis to produce energy since the mitochondria is damaged and there is not enough oxygen (see. Hypoxia) to go through respiration (oxidative phosphorylation)^[1]. Usually cells with a critical amount of damage (such as in cancer cells) kill themselves by apoptosis which requires properly functioning mitochondria. DCA restores the function of the mitochondria and thus apoptosis is restored. Cancer cells then begin killing themselves off.

DCA is still in the human testing trials in Canada, however it is available for purchase from websites and physicians. This off-label use of DCA to treat cancer has sparked an incredible amount of controversy. However the animal trials, and initial human tests proved promising.

References

↑ Xu R, Pelicano H, Zhou Y, Carew J, Feng L, Bhalla K, Keating M, Huang P (2005). "Inhibition of glycolysis in cancer cells: a novel strategy to overcome drug resistance associated with mitochondrial respiratory defect and hypoxia". Cancer Res 65 (2): 613–21. PMID 15695406.

[1] Xu R, Pelicano H, Zhou Y, Carew J, Feng L, Bhalla K, Keating M, Huang P (2005). "Inhibition of glycolysis in cancer cells: a novel strategy to overcome drug resistance associated with mitochondrial respiratory defect and hypoxia". Cancer Res 65 (2): 613–21. PMID 15695406.

[1]