Carcinogenic effects of cadmium on the prostate of the rat

The carcinogenic effects of cadmium were tested in an animal experiment to check the results of epidemiological studies showing that the incidence of prostatic carcinoma is above average in workers industrially exposed to high cadmium levels. For this purpose 1.9 mg CdCl2 (1.2 mg Cd/kg body weight) was injected into the right ventral prostatic lobe of 12-month-old male inbred rats of the Okamoto-toki strain. Simple hyperplasia was found in 38, atypical hyperplasia in 29, atypical hyperplasia with severe dysplasia in 11 and invasive prostatic carcinoma in 5 of 100 animals 270 days after the injection. Various mechanisms are discussed in connection with the carcinogenic action of cadmium.