PSA and the conservative treatment of early prostate cancer.

The large difference between the incidence of prostate cancer and mortality from this disease suggests that a large number of men do not require treatment. As a result of the epidemiologic trends observed, a growing number of urologists recognize that many men with newly diagnosed localized disease can be treated conservatively for many years without adverse consequences. We recently published a twenty-year update of the large cohort of men diagnosed with clinically localized prostate cancer in Connecticut. From this study we have learned that men with high-grade disease, specifically Gleason score 7-10 prostate cancers, have a significant risk of dying from their disease if left untreated. Men with low-grade disease (Gleason score 2-6 tumors) have a remarkably indolent course over a period of twenty years. Fewer than 20% of these men died from clinically localized prostate cancer when managed conservatively. Based on our analysis of over 1,800 men diagnosed with localized prostate cancer in Connecticut between 1990 and 1992, we found that during the past two decades there has been a significant shift in the use of the Gleason scoring system. Gleason score 2-5 tumors ten years ago are much more likely to be scored as Gleason 6 tumors in contemporary practice. Men with high-grade prostate cancers (Gleason scores 7-10) face a significant risk of disease progression and death if managed expectantly. Men with low grade prostate cancers (Gleason scores 6 or less) face a much more ambiguous outcome. Some researchers suggest tracking PSA doubling times as a way of separating those patients with indolent disease from those who are likely to experience progression.