Hypercalcemia in association with cutaneous squamous cell carcinoma. Occurrence as a late complication of hidradenitis suppurativa.

Squamous cell carcinoma of the skin is a rare complication of hidradenitis suppurativa. We treated a case of hidradenitis-associated squamous cel carcinoma with metastases to the inguinal lymph nodes. Hypercalcemia also occurred, possibly in relation to the secretion of a hormonelike substance by the tumor. Chemotherapy with bleomycin sulfate, methotrexate sodium, and cisplatin led to tumor regression and control of the hypercalcemia.