Frequency and number of neuroendocrine tumor cells in prostate cancer: No difference between radical prostatectomy specimens from patients with and without neoadjuvant hormonal therapy

Abstract

Neuroendocrine tumor cells in prostate cancer are thought to increase after hormonal therapy due to neuroendocrine differentiation of tumor cells. This assumption is based on the histological analyses of limited portions of the cancerous lesions examined. Radical prostatectomy specimens were obtained from 122 consecutive patients with prostate adenocarcinoma, 70 of whom underwent prostatectomy alone (Group A) and 52 with neoadjuvant hormonal therapy (Group B). Sections from all the 5-mm-thick slices from formalin-fixed specimens were immunostained for chromogranin-A, and the total number of choromogranin-A-positive neuroendocrine tumor cells were counted. No difference was found between Groups A and B in the frequency of cancer with neuroendocrine cells. The total number of neuroendocrine cells in cancer varied widely with no difference of median values in the two groups. These results do not support the assumption that hormonal therapy induces neuroendocrine differentiation, but suggest androgen-independent neuroendocrine cells existed before therapy.