Digital rectal examination

In this test, the doctor inserts a lubricated, gloved finger into the rectum and feels the surface of the prostate to determine whether it is swollen or has any lumps or abnormally textured areas (see Figure 1). This exam also helps doctors screen for diseases of the rectum, such as rectal cancer. When combined with a chemical test to determine the presence of blood in the stool (known as a hemoccult or fecal occult blood test), the digital rectal examination (DRE) is extremely effective in screening patients for a variety of gastrointestinal disorders, including stomach cancer, peptic ulcer disease, polyps, and hemorrhoids. The American Cancer Society advises that all men ages 50 or older have a yearly DRE. Studies have produced conflicting results, but one conducted by the Mayo Clinic demonstrated that men who get DREs are less likely to die from prostate cancer.

Although this exam generally takes less than a minute, some men find it uncomfortable and, most of all, embarrassing, so they postpone it or avoid going to a physician altogether. But the discomfort is mild and lasts only a few moments, and the procedure causes no physical injury.

The DRE is a useful screening test, but it isn’t foolproof. Its accuracy depends on the skill of the physician conducting and interpreting the test. Moreover, early cancerous tumors are often too small to detect during a DRE, and some are located in areas a doctor’s finger can’t reach. For these reasons, clinicians who use DRE alone to screen for prostate cancer sometimes miss the smallest and most treatable tumors. On the other hand, small tumors that can’t be felt by the physician may be less likely to cause future problems.