Immunohistological demonstration of calcitonin in endometrial carcinomas with and without argyrophil cells.

Sixteen endometrial carcinomas were studied by an immunoperoxidase method with anti-human calcitonin, 8 with and 8 without argyrophil cells. Calcitonin was demonstrated in 7 with and 2 without argyrophil cells. Calcitonin production was not associated with any specific histology of the endometrial carcinomas. Regardless of the existence of argyrophil cells, calcitonin was located in the apical portion or in the entire cytoplasm of the glandular tumor cells in the well differentiated adenocarcinomas. In a poorly differentiated adenocarcinoma and the adenosquamous carcinomas, it was found in many immature and squamous tumor cells as well as in some glandular tumor cells. The comparative studies between calcitonin and argyrophil granules in the endometrial carcinomas with argyrophil cells revealed that calcitonin was located in many tumor cells other than argyrophil cells. The extreme examples were 2 calcitonin-producing tumors without argyrophil cells. Calcitonin production of the endometrial carcinomas is a novel finding, but the biological significance of argyrophil cells remains to be further investigated.