ABSTRACT
A histopathological study was performed on nevus sebaceus to observe its aging effect based on 75 cases of neuvs sebaceus those were collected during the past 10 years from three university hospitals in Seoul. The results are as follows: 1) Clinical findings The incidence was most frequent in the teenage group. The 75 cases consisted of 41 males and 34 females with a sex ratio of 1.2:1. Most of cases developed in the head and neck areas with 62.7% on the scalp and 29.3% on the face. 2) Histopathologic findings. The epidermal changes such as acanthosis(40%), papillomatosis(73%), hypergranulosis(44%) were most remarkable in the second decade and gradually decreased with aging. The apparent proliferation of sebaceous gland was observed in 73% and it was most prominent in the second decade. Apocrine glands were absent before the first decade but apparently increased after then. Proliferation of eccrine gland was not significant in all the age groups. Mild increase of immature hair follicles were noted in 49% of our cases with gradually decreasing tendency in the older age. The dermal inflammatory infiltrates were noted from the 2nd decade(28%) and thereafter gradually increased. Associated neoplasms were one apocrine adenoma, one sebaceous adenoma, two trichilemmomas and two arteriovenous hemangiomas. The majority of tumors occured in the third decade. Therefore, it is observed that neuvs sebaceous undergoes dynamic histopathologic changes according to the age of patient and later develop various secondary neoplastic changes. The pathogenesis of the nevus sebaceus is suggested to be closely related with developmental anomalies of primitive hair germ units in fetal stage.