Stage B prostate cancer: Correlation of DNA ploidy analysis with histological and clinical parameters

Abstract

Background: The ability to accurately predict tumor behavior and patient survival is a problem in managing patients with prostate cancer. Prognostic variables in predicting death from tumor include prostate-specific antigen (PSA) level, histological grade, and clinical stage. Observer subjectivity is inherent in determining grade and stage; thus, criteria that are more objective are needed to identify patients for appropriate treatment. Methods: The authors correlated flow cytometric nuclear DNA ploidy with Gleason score, PSA level, and recurrence risk in patients who underwent radical retropubic prostatectomy and bilateral pelvic lymphadenectomy between 1987 and 1993 for histopathologic stage B prostate cancer (T2, N0, M0). Results: Of the tumors analyzed, 64% were DNA diploid with a low proliferative fraction, 25% were DNA diploid with a high proliferative fraction, and 11% were DNA aneuploid. DNA aneuploidy was associated with high Gleason grade (7-10). All Gleason grade 10 tumors were DNA aneuploid. Both DNA aneuploidy and high proliferative fraction (S+G2M) were statistically correlated with high Gleason grade and adverse prognosis but not with PSA level or patient age. Conclusions: A direct relationship is shown between both DNA aneuploidy and a high proliferation index with aggressive biological behavior in stage B prostatic cancer. Objective tumor criteria are needed to choose treatment more selectively for individual patients.