Multiple autotransplantation of rat mammary tumors induced by 7,12- dimethyl-benz[a]anthracene: brief communication

Mammary tumors induced in outbred Spraque-Dawley rats by 7,12-dimethylbenz[a]anthracene were excised, cut into 1- to 2-mm³ pieces, and then autotransplanted sc along the mammary line at six sites. Following an average period of 20-30 days, these autografts grew to approimately 2 cm in diameter in 32 of 48 rats (67%). Autografts in the other 33% of the rats remained dormant. Mammary tumors tansplanted into allogeneic hosts failed to grow. Tumors derived from autotransplantation were indistinguishable from their primary tumors with respect to their histologic features, the nature of hormone dependency, the content of estrogen receptors, and their ability to incorporate [³H]leucine. Furthermore, autotransplanted tumors derived from a single primary tumor varied little with regard to the preceding parameters; thus they provided an opportunity for serial sampling of individual tumors for repeated morphologic and biochemical evaluations.