Regressive changes and neuroendocrine differentiation in prostate cancer after neoadjuvant hormonal treatment

BACKGROUND. We studied the extent of neuroendocrine (NE) tumor cell differe ntiation and its relation to regressive changes in prostate cancer after 3- month hormonal treatment. METHODS. Radical prostatectomy specimens from 103 patients, randomized to 3 -month neoadjuvant LH-RH-analogue treatment (neoadjuvant group) or to surge ry alone (control group), were available for analysis. The effects of hormo nal treatment in terms of positive surgical margins, the degree of histopat hological changes, and tumor cell proliferation were evaluated in relation to NE-differentiation assessed with antibodies against chromogranin A (CGA) . RESULTS. Both the number of CGA-positive cells/cm(2) (P < 0.003) and the pr oportion of NE-positive tumors (P = 0.07) were greater in the neoadjuvant g roup than in the control group. No correlation existed between NE-different iation and the effects of the neoadjuvant hormonal treatment; nor did NE-di fferentiation correlate to the decrease in serum PSA. CONCLUSIONS. Neuroendocrine differentiation in prostate cancer increases af ter 3 months of neoadjuvant hormonal treatment but does not correlate to th e effects of hormonal treatment. Prostate 42:274-279, 2000. (C) 2000 Wiley- Liss, Inc.