Squamous cell carcinoma arising in dissecting perifolliculitis of the scalp. A case report and review of secondary squamous cell carcinomas.

Squamous cell carcinomas have been reported to arise within acne conglobata and hidradenitis suppurativa. A case report of a secondary squamous cell carcinoma (SSCC) arising in the third member of the follicular occlusion triad, dissecting perifolliculitis of the scalp (Hoffman's disease, perifolliculitis capitis abscedens et suffodiens) is presented. The fatal outcome of this case and a review of the literature emphasize the biologic aggressiveness of SSCCs arising in chronic inflammatory lesions or scars (Marjolin's ulcers). Compared to squamous cell carcinomas arising in actinic keratoses, the metastasis rate of these carcinomas arising in chronic inflammatory lesions is so high that early and aggressive therapy appear indicated.