증식성 모낭종 1례

Abstract

Proliferating trichilemmal tumor occurs predominantly over the scalp of women in the form of a single nodular lesion. Occasionally, the lesion appears in individuals with multiple trichilemmal cysts or shows involvement of a good portion of scalp with exophytic lesion or with a large plaque exhibiting surface nodularities. Histologically, the lesion is made up of proliferation of the outer root sheath epithelium with many central areas of trichilemmal keratinization and homogenous keratin cyst formation. The presence of low grade cellular atypia, individual cell keratinization, occasional dyskeratotic cells and mitotic figures may provide a false impression of an invasive squamous cell carcinoma. We are reporting a case of proliferating trichilemmal tumor in an 74-year-old woman with recent history of rapid enlagemnt of long shading exophytic scalptleision. Histologic section shows trichilemmal keratinization characterisic of a proliferating trichilemmal tumor. There were also abnormal mitosis, marked cellular plemorphism, and infiltrating margin suggesting malignant transformation.