Moles Atypical Nevi Information
Atypical mole syndrome consists of multiple clinically atypical nevi, together with an increased risk of melanoma. It occurs as a familial syndrome and also sporadically. Atypical nevus syndrome was described in 1978 in families whose members possessed large irregular nevi with a variegated color and a palpable dermal component. Several family members had a history of melanoma. These atypical nevi were considered to be a phenotypic marker for family members at increased risk for developing melanoma. Inheritance is thought to be autosomal dominant with variable penetrance.
These clinically and histologically distinctive melanocytic nevi occur as solitary lesions, as multiple lesions in sporadic cases, and as multiple lesions in the familial syndrome. In all three settings, atypical nevi are considered to be precursors for melanoma, most often the superficial spreading type. More than 90% of patients with familial melanoma have atypical nevi.