Bacillus of Calmette and Guérin and 7, 12-dimethylbenz(a)-anthracene carcinogenesis in mice.

The effects of single or repeated Bacillus of Calmette and Guérin (BCG) treatment on the onset of tumors induced by the carcinogen 7,12-dimethylbenz(a)anthracene (DMBA) injected at birth into Swiss mice were studied. Multiple doses of BCG, given at regular intervals significantly lowered the incidence of carcinogen-induced tumors. The DMBA-induced lung adenomas did not differ morphologically from the ones that appeared in mice simultaneously treated with both DMBA and BCG.