Squamous cell carcinoma and Crohn's disease: a sometimes-challenging diagnosis.

Non-melanoma skin cancers are more common in people with inflammatory bowel disease. However, these tumors can rarely mimic a cutaneous manifestation of the disease, which delays diagnosis and clouds prognosis. A 35-year-old man with stenosing and fistulizing ileocolic Crohn's disease developed squamous cell carcinoma mimicking a groin fold abscess. After surgical drainage of the abscess, despite antibiotics and therapy combining azathioprine with infliximab, the abscess has recurred. Biopsies revealed a cutaneous squamous cell carcinoma. Palliative radiotherapy-chemotherapy was initiated, but the patient died after 3 months. This observation illustrates the increased risk of non-melanoma skin cancers in inflammatory bowel disease patients, particularly those exposed to thiopurines, and the value of diagnosing them at an early stage.