IMPALPABLE INVISIBLE STAGE TIE PROSTATE-CANCER - CHARACTERISTICS AND CLINICAL RELEVANCE IN 100 RADICAL PROSTATECTOMY SPECIMENS - A DIFFERENT VIEW

Purpose: We analyzed 100 consecutive radical prostatectomy specimens t o evaluate the extent and clinical relevance of the stage Tie cancers discovered. Materials and Methods: All cases were diagnosed by systema tic prostatic puncture biopsies because of abnormal prostate specific antigen (PSA) or PSA density. Surgical specimens were examined with th e whole organ multiple step-section technique (4 mm.) to identify prim ary tumor location (peripheral or transition zone cancer), tumor volum e, tumor volume divided by prostate volume (percent tumor volume), Gle ason score, pathological T stage and positive surgical margins. Tumors smaller than 0.5 cm.(3) and without unfavorable pathology (Gleason sc ore 7 or more, or positive surgical margins) were considered insignifi cant. Results: Median patient age, PSA, tumor volume and Gleason score were 64 years, 8.8 mu g./l., 1.6 cm.(3) and 6, respectively. Of the s pecimens 46 (46%) had transition zone cancer that was clinically undet ectable due to anterior location, while peripheral zone cancers were s mall, diffuse, anterolateral or in large glands with low percent tumor volume. Transition zone cancer showed greater PSA, PSA density, tumor volume and percent tumor volume than peripheral zone cancer (p = 0.08 , 0.03, 0.0002 and 0.0004, respectively), yet with similar Gleason sco re (p = 0.4). Of the tumors 34 (34%) were locally advanced (stage pT3 and/or positive surgical margins, mostly anterior in 16 transition zon e cancers, and apical or posterolateral in 18 peripheral zone cancers) , whereas 22 were insignificant (6 transition and 16 peripheral zone c ancers). Prostatic puncture biopsies with a core cancer length of less than 3 mm. could have predicted 18 of 19 insignificant tumors but und erestimated 13 (33%) and 6 (17%) significant transition and peripheral zone cancers. Conclusions: The majority of our stage Tie tumors were significant with a distinguished high incidence of transition zone can cer. Therefore, they were large but occult. Transition zone cancer beh aved differently than peripheral zone cancer, and warranted considerat ions during treatment of stage Tie prostate carcinoma.