Prostate cancer is, in most (but not all) cases, a very slowly growing type of cancer. It is often said that if a man lives long enough, that he will likely develop prostate cancer at some point. This is said because autopsy studies show that nearly all men ages 90 and older have at least a little prostate cancer. Most men who have prostate cancer do not die of prostate cancer. This is especially true of elderly men diagnosed late in life.
These facts lead to an attractive option for some patients: if a man has a small amount of a slow-growing type of prostate cancer, and his age or health is such that his life expectancy is 10 years or less, he may consider not having any treatment at all for the cancer, at least initially. Under these circumstances, we can often safely follow these men conservatively by checking their PSA and perform an exam at intervals. Sometimes follow-up biopsies are recommended as well. Treatment can, of course, be started at any time that the patient and physician choose.