Mondo Description Clinically atypical nevi (usually exceeding 5 mm in diameter and having variable pigmentation and ill defined borders) with an increased risk for development of non-familial cutaneous malignant melanoma. Biopsies show melanocytic dysplasia. Nevi are clinically and histologically identical to the precursor lesions for melanoma in the B-K mole syndrome. (Stedman, 25th ed)

Uniprot Description A malignant neoplasm of melanocytes, arising de novo or from a pre-existing benign nevus, which occurs most often in the skin but also may involve other sites.