[Development of multiple precancerous conditions and malignant skin tumors in immunosuppressive therapy].

A 45-year-old patient developed squamous cell carcinoma 4 years after renal transplantation and immunosuppressive therapy with azathioprine and fluocortolone. During the following 3 years, the patient developed on sun-exposed skin several premalignant hyperkeratoses, Bowen's carcinoma, basal cell carcinoma, as well as squamous cell carcinoma and carcinoma of the eccrine sweat glands, both showing the clinical picture of keratoacanthoma.