Hidradenitis suppurativa complicated by squamous cell carcinoma and paraneoplastic neuropathy.

Squamous cell carcinoma is a rare complication of chronic, severe, hidradenitis suppurativa. We describe a patient with a 20-year history of extensive perineal hidradenitis suppurativa who presented with subacute muscle weakness and sensory symptoms. He was subsequently diagnosed with squamous cell carcinoma arising in the area of hidradenitis. The neurologic symptoms and signs resolved after complete excision of the tumor. This presentation is consistent with a paraneoplastic neuropathy, which has not been reported previously in patients with squamous cell carcinoma arising in patients with hidradenitis suppurativa.