Neuroendocrine differentiation in prostatic adenocarcinoma and its relationship to tumor progression

Abstract

Background. Neuroendocrine differentiation has been demonstrated by immunohistochemical preparations in many cases of acinar type prostatic adenocarcinoma (CAP). Some studies have suggested that this differentiation may indicate an adverse prognosis. Methods. Tissue samples from 38 consecutive patients with clinical Stage II (AJCC) CAP who underwent radical retropubic prostatectomy (RRP) were studied after preparations were made with antichromogranin (ChA) and neuron-specific enolase (NSE). All patients were followed for at least 4 years post-RRP or until disease progression was documented by rising serum prostate specific antigen concentration, X-ray evidence of recurrence, or a positive tissue biopsy. Results. Nine of the 38 RRP specimens (24%) were positive for NSE, and 11 (29%) were positive for ChA. Neither of these neuroendocrine markers showed a significant correlation with tumor progression. Neuroendocrine differentiation in needle biopsy specimens from these same patients (when available) did not correlate with tumor progression either. Of the patients with tumor progression, 9 of 11 (82%) had pathologic Stage III disease after RRP; of those with no progression of CAP, only 7 of 27 (26%) had pathologic Stage III disease. Conclusions. Neuroendocrine differentiation, as demonstrated by NSE and ChA preparations, was not helpful in predicting tumor progression of CAP.