The Digital Rectal Exam 

This is a useful diagnostic tool to screen for both colon and prostate cancers. In my experience, it is also the part of the examination that the patient most dreads -- but it is necessary.

According to the American Cancer Society, colorectal cancer screening guidelines for both men and women should begin at age fifty with one of the following:

1. Yearly stool blood test (FOBT) or fecal immunochemical test (FIT)

2. Flexible sigmoidoscopy every five years

3. Yearly stool blood test plus flexible sigmoidoscopy every five years

For the stool blood test, the take- home, multiple sample method should be used. (Of the first three options, the American Cancer Society prefers the third option, that is, FOBT or FIT every year plus flexible sigmoidoscopy every fi ve years.) Or you may have:

4. Double contrast barium enema every five years

5. Colonoscopy every ten years

A colonoscopy is recommended for all men over the age of fifty -- or earlier (age forty) for high- risk patients like African-Americans or men with a family history of prostate or colon cancer. Gay men should have a rectal exam beginning at age forty. After the exam is performed, a Guaiac Card is used to test for microscopic blood, also called the fecal occult blood test (FOBT), which is a screening test for colon cancer.

Colorectal cancer is the third most prevalent cancer found in men and women in this country. The American Cancer Society estimates that there were about 106,680 new cases of colon cancer and 41,930 new cases of rectal cancer in 2006 in the United States alone. Combined, they will cause about 55,170 deaths. The death rate from colorectal cancer has steadily decreased over the past fi fteen years, thanks, in part, to proper colorectal cancer screening, like the FOBT. Even with these startling numbers, the good news is that colorectal cancer can be cured if found early.

However, despite its utility, the FOBT misses one in three cancers. That is why a positive FOBT should be followed up with a fl exible sigmoidoscopy. This test, usually performed by a gastroenterologist, uses a fiberoptic tube that is inserted into the rectum to assess the lower colon. Polyps or any suspicious growth should be biopsied.

A colonoscopy, on the other hand, is a much more thorough examination of the entire colon. Patients must be prepped the night before with a powerful laxative to clean out the colon offering the doctor better visibility. It is performed in a hospital or a doctor's office, and the patient is given sedation during the procedure. Once again, polyps and suspicious lesions should be biopsied. If any polyps or suspicious lesion are detected, the procedure can be repeated the following year. If the colonoscopy is normal, it should be repeated every three to five years thereafter.