Chondrodermatitis nodularis chronica helicis: a perforating necrobiotic granuloma.

Seventeen cases of clinically and histologically characteristic chondrodermatitis nodularis chronica helicis (CNCH) are presented. Thirteen histologic specimens revealed transepidermal elimination (TE) of necrobiotic material from the dermis. This elimination occurred through transepidermal channels, slits, or erosions overlying a dermal necrobiotic granuloma. The granuloma was surrounded by granulation tissue composed of histiocytes and lymphocytes. Telangiectasia and peripheral solar elastosis were common findings. The histologic features and clinical characteristics found predominantly in white men over 40 years of age suggest that CNCH etiologically and pathogenetically represents an actinically induced perforating necrobiotic granuloma.