Neurocristic hamartoma (NCH) is an extremely uncommon, benign hamartoma of the skin and soft tissue that arises from abnormal migration and differentiation of pluripotential cells from the neural crest that show differentiation toward Schwann cells, pigmented dendritic spindle cells, and melanocytes.

NCH presents as a blue-to-black pigmented plaque most commonly located on the scalp that may be found on other areas of the head, face, neck, and back. When on the scalp, there is often accompanying alopecia; however, lesions may rarely show local hypertrichosis. Most cases are congenital, but NCH may be acquired.

Recognition of NCH is critical as malignant transformation to melanoma and subsequent metastatic disease can occur. Thirty-eight percent of reported cases to date have shown the development of melanoma, and 19% of patients displayed metastatic disease. Patients with congenital NCH tend to develop malignant degeneration with melanoma occurring within 15-67 years, whereas acquired lesions show more rapid progression to melanoma within 1-6 years.