Neuroendocrine differentiation and short-term neoadjuvant hormonal treatment of prostatic carcinoma with special regard to tumor regression

Objectives: Neuroendocrine (NE) differentiation in prostate cancer is belie ved by some authors to play an important role in the development of androge n resistance. However, there is little knowledge about the impact of short- term neoadjuvant hormonal therapy on NE differentiation and on whether the degree of tumor regression is linked with the extent of NE differentiation. Methods: NE cells were detected by immunohistochemistry using a chromograni n A antibody. The densities of NE cells in 20 pretreated and 20 nonpretreat ed radical prostatectomy specimens were compared. Furthermore, we compared the NE cell density in tumors with variable degrees of regression. Results:The median percentage of tumor cells showing NE differentiation did not significantly differ between pretreated and nonpretreated specimens (0 .61%, range 0.0-2.4%, vs. 1.47%, range 0.0-6.8%; p = 0.9896). Twelve nonreg ressive/slightly regressive tumor foci and 12 strongly regressive tumor foc i were assessed. The NE cell density did not differ significantly (p = 0.12 27). Conclusions: Short-term neoadjuvant hormonal therapy does not induce releva nt clonal propagation of NE cells. The degree of tumor regression following short-term neoadjuvant hormonal therapy does not correlate with the extent of NE differentiation. Copyright (C) 2001 S. Karger AG, Basel.