Objectives: The biology of prostate cancer is poorly understood. Despite established prognostic criteria, a confident prediction of the clinical outcome is not always possible. Therefore, additional and more precise information is highly desirable. In the present study, we compared potential biologic markers with the laboratory, clinical, and histopathologic parameters of prostate-specific antigen (PSA) level, tumor stage, and tumor grade.
Methods: Paraffin-embedded material from 62 radical prostatectomies for prostate carcinoma was examined immunohistochemically using monoclonal antibody Ki-S5 to determine the tumor growth fraction and antibody DO-1 to assess p53 protein overexpression. Deoxyribonucleic acid-ploidy was analyzed by flow and image cytometry. Preoperative PSA levels were assessed by standard method. The tumors were categorized according to the Gleason grading system and staged postsurgery after the TNM classification.
Results: The p53 expression, proliferation rate (Ki-S5), and rate of aneuploidy correlated closely with stage (P < 0.05) and Gleason score (P < 0.01). However, divergences were occasionally observed. The ploidy status correlated closely with proliferative activity and p53 expression. Conversely, no correlation was seen between these parameters and serum PSA content, the latter being significantly associated with the tumor stage alone.
Conclusions: The results characterize proliferation marker Ki-S5, p53 expression, and ploidy status as tumor biopotential markers, whereas PSA provides diagnostic information. Use of these investigative methods promises to provide additional information relevant in prognosis and therapy selection. Nonetheless, their precise prognostic value will have to be established in further studies.