[Immunohistochemical and morphometric studies on neuroendocrine differentiation of prostate carcinomas].

102 unselected and untreated prostate carcinomas were immunohistochemically analysed with regard to neuroendocrine (ne) differentiation using a monoclonal antibody against Chromogranin A. Density of ne-tumor cells/mm2 tumor area and arrangement of ne-tumor cells (single cells; small groups and large groups) were determined. We found ne-tumor cells in 90% of all carcinomas (n = 92). 70% had a low density of ne-tumor cells (< or = 1 cell/mm2). 67% of carcinomas with ne-differentiation showed only single ne-tumor cells, there were small groups in 19% and large groups in 14%. There was an association between higher densities of ne-tumor cells and arrangement in groups. In high malignancy carcinomas we found a higher density of ne-tumor cells and more often an arrangement in groups than in low grade tumors. Our results support reports in literature that ne-differentiation is of prognostic significance.