Cancer induction studies using different administrations of benzenediazonium sulfate in mice

Benzenediazonium sulfate (BD) was administered as 10 weekly subcutaneous injections at 25 micrograms/g b.w. and as 52 weekly oral gavages at 100 micrograms/g b.w. to Swiss mice, starting at 6 weeks of age. The subcutaneous administration induced tumors in the subcutis with an incidence of 8% in females. The oral treatment gave rise to lung tumors with incidences of 52% in females and 62% in males. In the untreated control female mice, no subcutaneous tissue tumor was observed, but the incidences of lung tumors were 28% in females and 38% in males. Histopathologically, the neoplasms were classified as fibrosarcomas of the subcutis and adenomas and adenocarcinomas of the lungs. In an earlier experiment, BD induced high incidences of subcutaneous tissue tumors in the same species when it was administered as 26 weekly subcutaneous injections at 10 micrograms/g. This indicates the length of treatment is paramount to the dose of carcinogen. The oral route, even though it was carcinogenic in the lungs, failed to elicit the development of cancer in the glandular stomach.