Inhibition of benzo(a)pyrene carcinogenesis in rats with vitamin C.

The s.c. infection of 10 mg benzo(a)pyrene dissolved in 1 ml tricaprylin induced in Wistar rats local malignant tumors, such as fibrosarcoma, rhabdomyosarcoma, and polymorph cell sarcoma. The growth of the tumors was relatively rapid, reaching weights of 140-155 g before rats died 142-168 days after the administration of the carcinogen. On the contrary, under the same experimental conditions, high doses of Vitamin C about 525 mg/day/rat administered orally in drinking water (total amount of Vitamin C 55 g/rat corresponding to 40% of their body weight ) inhibited to a great extent the benzo(a)pyrene carcinogenesis. Only one slowly growing rhabdomyosarcoma (13 g of weight) was developed showing characteristic damage of malignant cells and partial replacement of the neoplastic area with granuloma tissue. The significance ov Vitamin C for cancer prevention and treatment is discussed.