ABSTRACT
The study was concerned with the evaluation of effect of the extract of a human fetal organ, the umbilical cord, on development and growth of such transplantable tumors as Ehrlich's ascites tumor, sarcoma 37, sarcoma 180 and Zajdela's hepatoma as well as of dimethylbenzanthracene- and benzo(a)pyrene-induced cancer. In a subgroup of animals who had been vaccinated once or twice prior to inoculation of cells, a significant inhibition of growth of tumors of all the histologies except sarcoma 180 was observed alongside with a decrease in tumor incidence and partial resorption of ascitic fluid. Preliminary vaccination of rats interfered with dimethylbenzanthracene- and benzo(a)pyrene-induced carcinogenesis reducing tumor incidence and assuring longer latent period and slower progression of cancer.
