Immunohistochemical demonstration of peptide hormones in endometrial carcinomas

Sixty‐eight endometrial carcinomas were examined histochemically and immunohistochemically for the presence of amine‐containing or neurohormonal peptide‐containing cells, particularly in relation to argyrophil cells. Argyrophil cells, detected in 43 of the 68 endometrial carcinomas by the Grimelius method, were subgrouped into two types according to the distribution of argyrophil granules and the shape of the tumor cells. Type I was found in 7 tumors and type II in 39; 3 tumors contained both cell types. The argyrophilia of type II cells was diminished in varying degrees in some tumors by diastase digestion, although it was unchanged in type I argyrophil cells. Indoleamine was detected by the formaldehyde‐induced fluorescence method in type I argyrophil cells of four carcinomas. Immunohistochemically, somatostatin‐reactive cells were found in two well‐differentiated adenocarcinomas with argyrophilia; many of these cells corresponded to some of the type I argyrophil cells, although some were nonargyrophilic. Two adenosquamous cell carcinomas with type II argyrophil cells also contained cells that were immunoreactive with antisera against gastrin; however, they were nonargyrophilic.