A Clinical and Histopathologic Study of 154 Cases with Congenital Melanocytic Nevus / 대한피부과학회지

ABSTRACT

BACKGROUND: Congenital melanocytic nevus(CMN) is regarded as benign, however it can be transformed to malignant melanoma. Thus, careful follow-up is mandatory. OBJECTIVE: To identify the clinical and histologic characteristics of CMN METHOD: We evaluated the clinical characteristics of CMN from 154 patients diagnosed at the Department of Dermatology in Chonnam National University Hospital from January, 1993 to December, 2002. Histopathologic exam was done from 50 patients. RESULTS: Female was more common(62.3%) and most cases(96.8%) were clinically apparent at birth. Medium-sized nevi(1.5cm> or =, <20cm) was most common(75.3%). The commonest location was on the head and neck region(45.5%). Most lesions were brown, dark brown or black in color, and flat-surfaced or slightly elevated in contour. About half of the cases manifested excessive hair growth on the surface and the possibility to have hair was positively correlated with the size of CMN. Some cases accompanied with neurofibromatosis, nevus flammeus and vitiligo were observed. Large CMN, compared with medium-sized or small CMN, involved deeper in the dermis. In 25 cases(50%), nevus cells involved the skin appendages, nerves, and vessels. CONCLUSION: Medium-sized CMNs on the head and neck were most prevalent. Some cases were associated with other diseases, especially pigmentary and vascular disorders. There was positive correlation between the size of CMN and the possibility to be hairy and, larger CMN tended to involve deeper in lower reticular dermis.