Colorectal Cancer
Colorectal Cancer, malignancy of the large intestine, the lower portion of the intestinal tract, which consists of the colon and rectum. Although colon cancer can occur in any segment of the colon, it is most common in the sigmoid colon, the section closest to the rectum.
Two simple tests can detect most colorectal tumors while they are still in an early, easy-to-treat stage. The first test is the digital rectal examination, during which the physician uses a gloved finger to gently check the smoothness of the rectal lining. The second test is the fecal occult blood test, in which a small sample of the patient’s feces is smeared on a card coated with a chemical called guaiac, which reacts with blood. The card is analyzed in a laboratory for occult (hidden) blood. A positive result does not necessarily indicate the presence of cancer. Although most colorectal cancers bleed, so do benign conditions such as hemorrhoids.
Another test is fiberoptic sigmoidoscopy, in which a flexible instrument is inserted into the lower intestinal tract through the anus. This instrument has light-conducting fibers that enable a physician to visually examine the interior of the colon and rectum. A biopsy can be performed simultaneously with a special biopsy tool attached to the end of the sigmoidoscope. The tissue is then examined under a microscope for signs of cancerous cells.
Early diagnosis is a major factor in surviving colorectal cancer. It is recommended that people aged 50 years and older have a fecal occult blood test and a sigmoidoscopy. If the tests do not show cancer, a fecal occult blood test should be performed annually and one of the following screening options should be followed: a sigmoidoscopy every five years, a colonoscopy every ten years, or a double contrast barium enema every five to ten years. A digital rectal examination should also be performed at the time of each screening sigmoidoscopy, colonoscopy, or barium enema examination.
The primary treatment for colorectal cancer is surgery to remove the tumor. The surgery may be combined with radiation, chemotherapy, or both. Using a combination of high-dose radiation and chemotherapy prior to surgery makes it possible to avoid permanent colostomies in many patients who previously would have needed this procedure. A colostomy is a surgical procedure to create an artificial opening through the abdominal wall to the exterior of the body for elimination of wastes into a plastic bag.
If cancer has spread from the colorectal area to the lymph nodes or liver, surgery or chemotherapy used in combination with three drugs—fluorouracil, leucovorin, and irinotecan—prolongs the lives of some patients.
Two simple tests can detect most colorectal tumors while they are still in an early, easy-to-treat stage. The first test is the digital rectal examination, during which the physician uses a gloved finger to gently check the smoothness of the rectal lining. The second test is the fecal occult blood test, in which a small sample of the patient’s feces is smeared on a card coated with a chemical called guaiac, which reacts with blood. The card is analyzed in a laboratory for occult (hidden) blood. A positive result does not necessarily indicate the presence of cancer. Although most colorectal cancers bleed, so do benign conditions such as hemorrhoids.
Another test is fiberoptic sigmoidoscopy, in which a flexible instrument is inserted into the lower intestinal tract through the anus. This instrument has light-conducting fibers that enable a physician to visually examine the interior of the colon and rectum. A biopsy can be performed simultaneously with a special biopsy tool attached to the end of the sigmoidoscope. The tissue is then examined under a microscope for signs of cancerous cells.
Early diagnosis is a major factor in surviving colorectal cancer. It is recommended that people aged 50 years and older have a fecal occult blood test and a sigmoidoscopy. If the tests do not show cancer, a fecal occult blood test should be performed annually and one of the following screening options should be followed: a sigmoidoscopy every five years, a colonoscopy every ten years, or a double contrast barium enema every five to ten years. A digital rectal examination should also be performed at the time of each screening sigmoidoscopy, colonoscopy, or barium enema examination.
The primary treatment for colorectal cancer is surgery to remove the tumor. The surgery may be combined with radiation, chemotherapy, or both. Using a combination of high-dose radiation and chemotherapy prior to surgery makes it possible to avoid permanent colostomies in many patients who previously would have needed this procedure. A colostomy is a surgical procedure to create an artificial opening through the abdominal wall to the exterior of the body for elimination of wastes into a plastic bag.
If cancer has spread from the colorectal area to the lymph nodes or liver, surgery or chemotherapy used in combination with three drugs—fluorouracil, leucovorin, and irinotecan—prolongs the lives of some patients.