Experimental Carcinogenesis in Submandibular Glands of Hamsters

Abstract

When 0.05 cc of 0.5 per cent (250 mg) 112 dimethylbenz (a) anthracene dissolved in liquid petrolatum was injected into the submandibular glands of 3-month-old hamsters, fibrosarcomas were induced between 10 and 14 weeks. The sequence of microscopic changes were, in order, degeneration of the parenchymatous and stromal tissue of the gland in the immediate environs of the infection site, fibrosis, and its subsequent transformation into fibrosarcomas of varying gradations. No changes of any significance were, however, noticed in the control glands. The tumor yield at the end of 18 weeks increased from 7.7 to 55.4% with the change in concentration from 0.1 (50 mg) to 1.0% (500 mg). The number of tumors induced did not vary with age, up to 9 months, all other factors being constant.