Indian Journal of Veterinary Pathology

The present study was aimed to access the progressive histopathological changes in experimentally induced skin carcinogenesis in rats. Skin carcinogenesis was induced in male Wistar rats with repeated low dosage topical application of dimethylbenz[a] anthracene (DMBA) at 1.28 mg/0.128 ml acetone thrice weekly for a period of 20 weeks. The rats were sacrificed periodically at 4 weeks interval up to 20 weeks. Histologically, the progression of precancerous lesions like hyperplasia, dysplasia and carcinoma in situ to benign papilloma and early invasive squamous cell carcinoma were recorded. A repeated low cumulative dosage of topical DMBA for 20 weeks enhanced the early onset of precancerous and cancerous lesions, and evaluation of histopathogenesis could be useful in therapeutic assessment of drugs or natural compounds for their chemopreventive efficacy.