The development of squamous cell carcinoma complicating hidradenitis suppurativa of the perianal region is reported. The patient, a 44-year old white male, had suffered from hidradenitis for 23 years. Malignant change was not confirmed pathologically until the eighth biopsy examination.
The literature of hidradenitis suppurativa and malignancy in the disease is reviewed. The relation of hidradenitis suppurativa to the follicular occlusion triad is discussed.