Colon Cancer

Colon cancer is unregulated cell replication and accumulation in the colon. Colon cancer is often called colorectal cancer. Colorectal cancer ranks as the fourth most common cancer in the United States among men and women.

Colon cancer is more frequent in obese individuals. In 2002, 41,000 cases of colon cancer were due to obesity in the United States. Studies have shown increase of colon cancer with higher body mass index (BMI) and abdominal obesity. Increased levels of insulin in obese individuals have been suggested to play a role in colon cancer.

Food enters the colon after becoming digested by the stomach and the small intestine. The colon removes water, nutrients, and forms stool from food. When colon cancer spreads to other parts of the body, the cancer is still recognized as colorectal cancer because the abnormal cells are the same. Colorectal cancer spread to the liver is diagnosed and treated as metastatic or distant colorectal cancer. The liver and lymph nodes, which are immunological filters from foreign bodies, are common locations to where colon cancer spreads.

Factors that may increase individual risk for colon cancer include age over 50, colorectal polyps (extra tissue growths in the colon), family history, inflammation of the colon, poor diet, and smoking. The non-polyp-inherited cancer, HNPCC, is more common than the polyp-inherited cancer, FAP. Inherited colon cancers can be detected by genetic testing. Studies have shown with diets high in fat and low in calcium, folate, fiber, fruits, and vegetables to increase the risk of colorectal cancer.

Detecting immunologic proteins in the blood common in cancer patients or a bloody stool test can screen for colon cancer. A lighted tube, such as a sigmoidoscope or colonoscope, is used to examine the colon for polyps. Polyps and tumors can also be detected with X-ray procedures. The detection of polyps may be followed by a tissue sample check for cancer cells. Ultrasounds, X-rays, computerized axial tomography (CAT) scans, and magnetic resonance imaging (MRI) may be used to determine if the colon cancer has spread to other areas. Symptoms of colon cancer include diarrhea, constipation, bloody or narrow stools, bloating, loss of weight, nausea, vomiting, and feeling tired. Colon cancer can be categorized in five stages (0–IV). Higher stages are categorized by the deeper penetration of the cancer in the colon wall and the spread to other parts of the body.

[Page 152]Cancerous polyps are surgically removed, which is the most common treatment. Sections of the colon with cancer cells may also be surgically removed. Radiation and chemotherapy are also used to attack cancer cells. Exercise, fruits, vegetables, and fiber intake are often recommended to prevent colon cancer.