CELL-PROLIFERATION AND APOPTOSIS IN PROSTATE-CANCER - CORRELATION WITH PATHOLOGICAL STAGE

Gleason grade, especially at low and high ends of the spectrum, is a k nown predictor of pathologic stage. What are needed are predictors of stage with Gleason sum 5 to 7 tumors, which encompasses the majority o f clinically organ-confined tumors, In this study, we analyzed whether cell proliferation and apoptosis (programmed cell death) were correla ted with stage in men with clinically organ-confined Gleason sum 6 to 7 cancer, We studied 98 radical prostatectomies with the following pat hologic stages: organ-confined disease (n = 28); capsular penetration (n = 28); seminal vesicle invasion (n = 21); and pelvic lymph node met astases (n = 21), Histological sections from the radical prostatectomi es were stained for cell proliferation using MIB1 antibody (Ki-67) and for apoptosis using the TUNEL technique. The extent of staining was r ecorded as the number of positive cells per 1000 cells, Overall daily growth (kp) was calculated as: kp = (ki/2) (apoptosis/0.5), based on t he time of prostate cancer to undergo mitosis and apoptosis per day, U sing logistic regression analysis, pathologic stage did not correlate with cell proliferation, apoptosis, or overall daily growth, These par ameters also did not distinguish between Gleason sum 6 and Gleason sum 7 tumors, We supplemented these cases with examples of Gleason sum le ss than or equal to 4 and Gleason sum greater than or equal to 8 to st udy cell proliferation and cell death in the full spectrum of Gleason grades, There was a significant difference (P = 0.005) in cell prolife ration between Gleason sum greater than or equal to 6 and Gleason sum less than or equal to 4 tumors, but apoptosis and daily growth were no t significant, We conclude that cell proliferation and apoptosis do no t correlate with pathological stage in clinically organ-confined cance r with Gleason sum 6 or 7, but that cell proliferation can distinguish between high (Gleason sum greater than or equal to 6) and low (Gleaso n sum less than or equal to 4) grade tumors.