Pararenal angiosarcoma induced in male mice by 1,2-dimethylhydrazine--a model for studying the role of androgens in chemical carcinogenesis.

CBA male mice treated with 1,2-dimethylhydrazine (DMH) developed high incidence (up to 97%) of pararenal angiosarcomas. Castration that preceded DMH-treatment almost completely inhibited the induction of these tumours while castration that followed DMH-treatment had on influence on their development. Testosterone propionate (TP) was efficient in restoring the incidence of DMH-induced pararenal tumours in castrated males only when given simultaneously with DMH and was totally inefficient when given after the cessation of DMH-administration. Castrated CBA female mice developed 92% of pararenal angiosarcomas when they received combined treatment with DMH and TP; no such tumours appeared in the intact females treated with DMH alone. The incidence of pararenal tumours in males of different strains was as follows: CBA, 97%; (CBA X C57Bl)F1, 36%; C57Bl, 4%; C3H, 35%; BALB/c, 13%; C3HA, 7%.