No abstract

Approximately half of the tumors missed with PSA 0 to 4 ng./ml. had aggressive characteristics (Gleason score 7 or greater, Gleason 4-5 components) and were organ confined. These tumors should be diagnosed and treated according to the present understanding of their natural history. More sensitive and selective screening strategies are needed. Presently a wrong "window of opportunity" is used for early detection of prostate cancer.

Reduced p27(kip1) expression is an independent predictor of poor outcome in prostate cancer, while MIB-1 is not. Decreased expression of CD44s yields additional information in predicting clinical recurrence. These tissue markers may identify patients at risk for disease recurrence after retropubic radical prostatectomy who may benefit from adjuvant therapy.

PSA testing was moderate in the control arm but if different men undergo this test each year, the contamination rate may become rather high. In the final analysis of mortality PSA testing should be considered.

Screening for prostate cancer leads to an increase in surgical treatment for relatively small tumors that have a higher probability of being organ confined. Although the frequency of positive lymph nodes at operation decreases dramatically and the proportion of organ confined tumors after surgery increases, there is a shift from Gleason 8 to 10 tumors towards lower grade tumors at radical prostatectomy. Still, judged by the high frequency of focal dedifferentiation in screen detected tumors, most of them and surgically treated tumors are likely to be clinically important. The relatively large accumulation of these tumors in the Gleason 7 category is a concern because it could lead to a decrease in the clinical usefulness of the Gleason score system.