Squamous cell carcinoma in localized scleroderma following immunosuppressive therapy with azathioprine

A 40-year-old man presented with an ulcerated tumour in a fibrotic plaque on the dorsum of his left foot. Due to severe localized scleroderma, the patient had been treated with azathioprine 10 years earlier. Histopathology of the excised tumour revealed an anaplastic squamous cell carcinoma within a scar of localized scleroderma. The case demonstrates that not only patients with tense scar tissue following burning, congelation, chronic radiodermatitis, lupus vulgaris or lupus erythematosus but also patients who have had localized scleroderma may run a greater risk of developing squamous cell carcinoma. Immunosuppressive therapy has to be discussed as an additional risk factor in our patient. Therefore, narrow clinical follow-up was recommended for early detection of relapse.