What is cancer!?
CANCER is very common disease of industrialized nations, currently causing slightly in excess of 20 percent of all deaths in the United States. Some one million new cases are diagnosed each year, with half a million deaths annually.
The incidence of cancer has increased sixty times since 1800, and the risk of cancer for men born in the 1950s is three times higher than for men born in the 1880s. Since 1958 alone, the incidence of cancer in men has increased 55 percent. The curve of cancer incidence rises steeply after the age of 60. A number of potential contributing causes have fueled the increase.
Anatomy and Physiology
Cancer is a distorted, wild, uncontrolled growth of portions of body tissues or organs in which cells multiply rapidly without restraint, producing a family of descendants that invade and destroy the structure and function of adjacent normal tissues in the organ from which the tumor originated.
Cancerous cells can travel through the bloodstream or lymph channels to lodge elsewhere in the body, starting new growths (metastases) and compromising the function of organs to which the cells spread. The initiatory phase of cancerous growth is triggered by a distortion in the DNA command apparatus of the nucleus of body cells.
Many authorities believe that human beings in a single lifetime experience cancer many times and that on most occasions the immune chemical and cellular defenses defeat the new growth so quickly that no symptoms ever make themselves known.
These authorities believe that we should pay more attention to the state of the immune system, which for a variety of reasons, occasionally fails to recognize and eliminate these early growths before they can become a threat. Damage to DNA in cell nuclei from free radical proliferation appears to play a key role in initiation and promotion phases of cancer.
Symptoms and Diagnosis
The classical warning symptoms of cancer are:
• The appearance of a new and growing palpable lump
• The sudden and continuing enlargement in a palpable lymph node or gland, most easily felt in the groin, underarm, and neck areas
• The appearance of unexplained bleeding from the mouth, throat, lungs, bladder, vagina, rectum, or skin lesion
• A noticeable change in size, color, or shape of a birthmark, mole, or skin blemish
• A noticeable change in function of a major organ; for example, unusual persistent diarrhea, constipation, difficulty swallowing food, or cough
• Fatigue of new onset or unexplained weight loss
Following preliminary diagnosis by the taking of a history, performing a physical examination, and obtaining certain laboratory tests and X-rays, the definitive diagnosis of a cancer depends on the obtaining of a sample of the apparent tumor by surgical or needle biopsy.
Following the pathological description of the cancerous tissue, the standard approach is to attempt surgical excision or removal of the entire cancer or, failing that, most of the cancer. Many patients at this juncture are then advised to undertake further therapy to destroy the remainder of the tumor or prevent recurrence from tiny amounts of tumor unknowingly left behind at surgery.
Cancer Chemotherapy, with varying combinations of chemicals that are destructive to rapidly multiplying cells, is used to attempt to destroy cancerous tissues manifesting uncontrolled growth. Chemotherapy is highly successful in Hodgkin’s lymphoma, certain testicular and kidney cancers, and childhood leukemias. However, 70 percent of women with breast cancer whose lymph nodes are free of cancer at the time of surgery are cured without chemotherapy.
Chemotherapy destroys not only rapidly multiplying cancer cells but rapidly multiplying immune cells as well. Patients may actually die from irreversible suppression of the immune system from the chemotherapy. This suppression limits the effectiveness and potential for chemicals to destroy all cancer cells. Many combinations of chemotherapeutic drugs cause side effects, including nausea, loss of appetite, diarrhea, weight loss, hair loss, and fatigue. Additional hazards include the appearance of secondary cancers later in life arising from the free radical damage from the original chemotherapeutic and radiation treatment.
Cancer Radiation, in the form of X-ray and radioactive isotope exposure, is used to destroy localized areas of remaining cancer. Radiation, too, has side effects: inflammation in surrounding normal tissues, diarrhea when the bowel is exposed, and degrees of nausea, loss of appetite, and fatigue.
In some types of cancer, including leukemias, radiation is used to destroy the blood-cell-producing bone marrow, after which the patient is given a bone marrow transplant. Patients must then take immune suppressant drugs to avoid rejection of the transplanted bone marrow.
Newer techniques used in certain cancers involve the use of vaccines and tagged antibodies made from tumor tissue itself. Conventional treatment also now encompasses chemoprevention (e.g., tamoxifen or raloxifen for women with and at high risk for breast cancer).
Cancer Immunotherapy. In late-stage melanoma patients treated with a vaccine made from irradiated, cultured melanoma cells harvested from lymph node biopsies, four year disease free survival of 47 percent greatly exceeded the usual surgical survival of 20 percent. Similar work is proceeding in using vaccines developed from biopsy material in lymphomas.
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