Decreased incidence of renal tumors in DMN treated Balb/C mice after orchiectomy.

Dimethylnitrosamine (DMN) induced a significant incidence (45.5%) of kidney epithelial tumors in adult male Balb/C mice. The proportion of mice with renal tumors orchiectomized after DMN injection was reduced to 25.6%; whereas the proportion of tumor bearing animals at other sites, such as lung, liver, and lymphatic tissue, increased compared to intact DMN treated animals and controls. This experiment confirms other studies in rats and mice showing that androgens play a role in initiation and progression of nitrosamine induced renal cancer, paralleling the finding of increased male susceptibility in human renal cancer.