Tumors Produced by Adenovirus 12 in Mastomys and Mice

Newborn Mastomys [Rattus (Mastomys) natalensis] and newborn C3H/Bi mice were inoculated witb human adenovirus 12. Some of the animals were inoculated subcutaneously, some intracerebrally, and some by both routes. Tumors were observed in 2 of 32 Mastomys after 5 to 6 months and in 7 of 29 mice after 2½ to 6 months. Histologically, the tumors were similar to those described by Trentin and his associates and by Huebner and his associates in Syrian hamsters inoculated with adenovirus 12, and we have classified them as “undifferentiated malignant tumors.” Transplantation of one of the mouse tumors was attempted, and it was serially transplantable in C3H/Bi mice. Attempts to isolate virus from the tumors were unsuccessful.