'Atypical' blue nevus--a benign variant of cellular blue nevus. Presentation of three cases.

Three cases of 'atypical' blue nevus presented almost identical histological findings differing from both benign cellular blue nevus and malignant blue nevus or malignant melanoma, and suggesting malignancy. Long-term follow-up--in one case 19 years--indicates that this pigmented tumor is a benign variant of blue nevus.