[Early melanoma as opposed to a benign nevus, nevus-associated melanoma, or halo nevus with regression?].

A 43-year-old woman, in whom a melanoma associated with a melanocytic nevus had been removed 2 years previously, came for a follow-up examination presenting with two light brown to medium brown maculae measuring approximately 7x5 mm with a flat papular center. One of the lesions was surrounded by a large white halo about 2 mm in size. The differential diagnosis on clinical grounds included a halo nevus with a second common nevus, a nevus with regression, and a melanoma associated with a nevus. Under the dermatoscope, an unremarkable homogeneous/reticular pattern could be seen and in one portion hallmarks of regression, namely gray tones and distinct gray-black dots. The diagnosis based on histopathological analysis was that of an atypical congenital nevus with regression.