Experimental mammary radiation carcinogenesis at the tissue level

This article reports on a study to evaluate the histological changes in a sample of mammary tissue irradiated in vivo with radiations of different LET and grafted to an ectopic site (dorsum) of an isogenic recipient. Two types of recipient animal were utilized: one with an artificially elevated plasma oestrogen level and a second with a normal hormonal status. Irradiations were performed with 1 and 2 Gy 15 MeV neutrons and 4 and 8 Gy 300 kV X rays. Inguinal mammary glands from whole-body irradiated 6 to 8-week-old female Sprague-Dawley rats were transplanted into an isogenic recipient. On the whole, the study shows that the technique of in vivo irradiation and subsequent transplantation of mammary gland tissue to an ectopic site is successful and reproducible. (Auth./C.F.)