Carcinogenic effects of diethylstilbestrol in male Syrian golden hamsters and European hamsters.

The tumorigenic effects of sc-implanted diethylstilbestrol (DES) on male Syrian golden hamsters and European hamsters were compared. The adenohypophyses, kidneys, and testes of both species showed neoplastic responses to DES treatment. European hamsters were more sensitive than were Syrian hamsters, inasmuch as the European hamsters had a higher tumor incidence. The testicular tumors were all Leydig cell adenomas and seemed to depend on the coincident occurrence of hypophyseal neoplasms (all composed of gonadotropic cells). Of the European hamsters tested, 29% also developed liver tumors (hepatocellular adenomas, carcinomas, and cholangiocarcinomas.