Q: My brother was operated on for prostate cancer. Does that mean that I have an increased danger of getting prostate cancer?
A: A number of studies have shown that men have a significantly higher risk of developing prostate cancer if other family members have the disease.
The magnitude of the increased risk depends on three factors: the number of family members affected, the closeness of the family relationship, and the age of diagnosis of prostate cancer in the family member. The risk is greater if the affected family member is a first-degree relative (father or son) rather than a second-degree relative (such as grandfather or uncle, or either the paternal or maternal side).
The risk is increased somewhat more if the disorder is discovered in one first-degree relative before they reach the age of 55; the risk is seven-fold higher if two or more other first-degree relatives develop prostate cancer at such an early .. age. There appears to be no increased risk if your brother (or father) was more than 70 years old when prostate cancer was diagnosed so long as no other family member has the disease. It is not clear if familial prostate cancer is due to the inheritance of an abnormal gene or to exposure to an identical environmental carcinogen.
These findings indicate that you, and others with a family history of prostate cancer, should have regular measurements of prostatic specific antigen (PSA test) and a digital rectal exam to pick up the earliest possible evidence of prostate cancer. The good news is that there is no evidence that prostate cancers are more prone to spread in people with other affected family members.
Dr. Margolis is professor of medicine and biological chemistry at the Johns Hopkins School of Medicine.