Changing pigmentation in a solitary scalp lesion.

A healthy 66 year-old man presented with a complaint of changes within a nodule on the scalp, which had first appeared over 10 years prior. He had no previous history of skin cancer. On physical examination a solitary, asymmetric, purple-black nodule with irregular borders was identified on the right vertex of his scalp. The remainder of his examination did not reveal any additional lesions.