Neoplastic lesions in streptozotocin-treated rats

Pathological examination was carried out on 16 male Sprague-Dawley rats received single i. v. injection of 60 mg/kg of streptozotocin (SZ) at 5 weeks of age and maintained for 22 months. Insulinoma (63%), renal adenoma (50%), hepatocellular tumor (69%), cholangioma (31%) and Leydig cell tumor (56%) were found in a high incidence, and therefore occurrence of these tumors was considered to be attributable to the treatment with SZ. In addition to these tumors, though in a low incidence, various such tumors as leukemia, reticulum cell sarcoma, mammary tumor and glioma were also found.