DNA-PLOIDY AND SURGICALLY TREATED PROSTATE-CANCER - IMPORTANT INDEPENDENT ASSOCIATION WITH PROGNOSIS FOR PATIENTS WITH PROSTATE CARCINOMA TREATED BY RADICAL PROSTATECTOMY

The authors addressed the following question: Does DNA ploidy measurem ent provide additional unique prognostic information beyond the custom ary parameters of tumor stage and histologic grade for patients with p rostate adenocarcinoma? They analyzed 494 patients treated by radical retropubic prostatectomy and bilateral pelvic lymphadenectomy at the M ayo Clinic from 1967 to 1981, pathologic stages B (n = 258), C (n = 14 5), and D1 (n = 91). Clinical follow-up was a minimum of 10 years. Nuc lear DNA ploidy patterns were measured with the archival paraffin embe dded specimen blocks using the Hedley technique. Univariate analysis d emonstrated that DNA ploidy, Gleason score, and pathologic stage are a ll highly important prognostic variables, each with a log-rank P value of <0.0001 for progression and cause-specific survival. Multivariate analysis indicates that DNA ploidy, pathologic stage, and Gleason scor e are each independently important prognostic variables for progressio n and cause-specific survival. DNA ploidy is particularly useful for d ifferentiating prognosis of patients with the common intermediate grad e (Gleason 5-7) tumors, which constituted 76% of this series. For this data set, prognostic risk after radical prostatectomy is summarized b y tables that take into account each of these three synergistic, indep endent variables. Within each Gleason score and pathologic-stage group ing, tumors with a nondiploid DNA content had roughly a 2.7-fold highe r chance of disease progression or of causing cancer death than DNA di ploid tumors.