Objective: To evaluate whether DNA ploidy and immunohistochemistry performed in primary prostatic carcinoma specimens give predictive information on regional lymph node metastasis in addition to T category, histological grade and serum prostate specific antigen (PSA).
Patients and methods: Pre-treatment TURP specimens from 80 patients with prostatic carcinoma T0-T3/M0 disease were retrospectively evaluated by means of DNA ploidy and histological grade, and immunostaining for PSA, prostatic acid phosphatase (PAP), neuron-specific enolase (NSE) and p53 protein. Pelvic lymph node dissection was performed in all patients. Serum PSA was determined in 76 of the 80 patients before pelvic staging lymphadenectomy. Thirty-two (40%) of the 80 patients had pN+ disease.
Results: Thirty-six patients (46%) had serum PSA values below the upper reference limit (< or = 10 micrograms/L). By univariate analysis the pN category correlated with the serum PSA level (P < 0.001), histological grade (P < 0.001), tissue PSA (P < 0.001), tissue PAP (P < 0.04), T category (P < 0.005) and DNA ploidy (P < 0.02). Multivariate analysis revealed that the serum PSA level was the most powerful independent prognosticator, followed by the T category, tissue PAP and tissue PSA. Histological grade and DNA ploidy did not reach the level of significance in the multivariate analysis.
Conclusion: These data suggest that tissue PAP and tissue PSA predict the pN status in patients with T0-T3/M0 prostate carcinoma, in addition to serum PSA and T category. Neuroendocrine differentiation and p53 protein seem to have no predictive ability.