Blue nevus of the uterine cervix.

The clinical, gross pathologic, and light and electron microscopic features of three blue nevi of the endocervix were studied. Immunocytochemical studies for the localization of S-100 protein in the blue nevus cells were performed. A comprehensive review of 47 previously published cases is also presented. Blue nevi of the endocervix appear to be rare incidental lesions; they are often found in hysterectomy specimens from middle-aged women. The lesion is seldom detected clinically or colposcopically. However, it appears in most instances as a blue-black lesion in the posterior wall of the endocervix on gross pathologic examination. The demonstration of S-100 protein in the blue nevus cells before and after bleaching in the present study, along with the ultrastructural observations, supports combined melanocytic and schwannian differentiation of the blue nevus cell.