Squamous cell carcinoma azathioprine

Skin carcinoma (predominantly squamous-cell carcinoma), cancer of the lip, Kaposi s sarcoma, and carcinoma of the cervix and anus are reported to be more common following azathioprine than in the general population (72). 

There is limited evidence of carcinogenicity of azathioprine in experimental animals. Studies with rats produced squamous cell carcinomas of the ear duct after administration at 150 mg kg in the diet for 52 weeks and lymphomas of the thymus gland under other conditions. In mice, intraperitoneal injections at 40 mg kg in 1-4-day-old offspring produced leukemia and long-term studies produced lymphoma and hemangiodothelioma of the uterus. 

Cohen S, Erturk E, Skibba J, and Bryan G (1983) Azathioprine induction of lymphomas and squamous cell carcinomas in rats. Cancer Research 43 2768-2772. 

Tumorigenicity The increased risk of squamous cell carcinoma in patients who are immunosuppressed by azathioprine has been reviewed [134 ]. 

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