Cancer is a group of diseases characterized by an uncontrolled growth of abnormal cells. If the spread of these abnormal cells is not controlled, cancer can cause death. Most cancers take the form of tumors, although not all tumors are cancers. A tumor is simply a mass of new tissue that serves no physiological purpose. It can be benign, like a wart, or malignant, like cancer. Benign tumors are made up of cells similar to the surrounding normal cells and are enclosed in a membrane that prevents them from penetrating neighboring tissues. They are dangerous only if their physical presence interferes with bodily functions. A malignant tumor, or cancer, is capable of invading surrounding structures, including blood vessels, the lymph system and nerves. It can also spread to distant sites by the blood and lymphatic circulation and so can produce invasive tumors in almost any part of the body.
In 1997, an estimated 1,359,150 people in the United States will be diagnosed with cancer and 554,740 will die of the disease. Early screening for cancer is believed to be able to drastically reduce the number of deaths due to the disease. Knowing what to look for when detecting cancer, as well as knowing if you are in a high-risk population are two of the main factors of early intervention. Early intervention of cancer has proven to increase survival rates and lower the length and severity of treatments. Detection and protection are two types of ambulatory care for cancer that begin before the disease is ever diagnosed.
Cancer often causes symptoms that you can watch for. These include: change in bowel or bladder habits; a sore that does not heal; unusual bleeding or discharge; thickening or lump in the breast or any other part of the body; indigestion or difficulty swallowing; obvious change in a wart or mole; and nagging cough or hoarseness. These symptoms are not always warning signs of cancer. They can also be caused by less serious conditions. It is important to see a doctor if any of these symptoms occur. Only a doctor can make a diagnosis. A person shouldn't wait to feel pain because early cancer usually does not cause pain.
Observation is the most widely available examination for the detection of cancer. It is useful in identifying suspicious lesions in the skin, lip, mouth, larynx, external genitalia and cervix. The second most available detection procedure is palpation. It is particularly valuable in detecting lumps, nodules, or tumors in the breast, mouth, salivary glands, thyroid, subcutaneous tissues, anus, rectum, prostate, testes, ovaries and uterus and enlarged lymph nodes in the neck, axilla or groin.
Internal cancers require an extension of observation through endoscopes, x-rays, magnetic resonance imaging, and ultrasound. Laboratory test, such as the Pap smear, and occult blood testing of the feces have also proven helpful for some of the cancers. However, concerns...