Hepatic cytologic and neoplastic changes in mice given benzidine dihydrochloride.

The administration of benzidine dihydrochloride in water to mice for up to 39 weeks resulted in hemosiderosis of the spleen, focal vacuolization of the transitional epithelium of the urinary bladder, and chronic inflammation and cytologic and neoplastic changes in the liver. Basophilic and acidophilic cytologic foci appeared in the liver as two distinct entities and both appeared preneoplastic. Benign and malignant liver tumors were also seen. Both types of cytologic changes and malignant liver tumors were more common in the female than male mouse.