Abstract
Summary
The effects of Bacillus Calmette Guerin on the development of spontaneous virus induced mammary adenocarcinomas in the mammary tumor prone R III strain of mice was investigated. A single injection of 1 × 106 infectious units of living BCG administered to mice between 3 to 4 weeks of age was found to significantly inhibit the rate of development of mammary adenocarcinoma as compared to control mice receiving a placebo injection of medium only. The incidence of spontaneous mammary tumors was essentially identical in both groups (96 vs 98%). However, mammary tumors developed at a consistently later time in the BCG treated animals as compared to the appearance of tumors in the control mice. Mice injected with BCG during the 2nd and 3rd month of life showed a moderately slower rate of development of tumors as compared to animals injected during the 3rd and 4th weeks of life. The possible role of BCG in nonspecific stimulation of resistance to the tumor virus mediated by immunologic factors seems likely.
Get full access to this article
View all access options for this article.