The endocrine component of prostatic carcinomas, mixed adenocarcinoma-carcinoid tumours and non-tumour prostate. Histochemical and ultrastructural identification of the endocrine cells.

Two types of endocrine-paracrine (EP) cells have been detected histochemically and ultrastructurally in normal and hyperplastic prostates; i.e. type I cells resembling intestinal EC (enterochromaffin) cells and type 2 cells similar to urethral EP cells previously reported by Casanova et al. (1974). About one-third of the 40 prostatic carcinomas studied contained EP cells: two of these were composite tumours exhibiting both adenocarcinomatous and carcinoid patterns. These four tumours have also been studied histochemically and ultrastructurally. ACTH and beta-endorphin immunoreactive cells, ultrastructurally resembling pituitary corticotrophic cells, have been identified in three tumours. Cells identical with type I and type 2 cells of the normal prostate were detected in two cases and in a further case, respectively.