Lentigo maligna has occasionally been noted to have the capacity to invade and repigment grey hairs. We present a case of a 78-year-old male who presented with a patch of brown hair on the vertex of the scalp in an area of previously white hair. The patient had previous radiotherapy to the site as a child for the treatment of tinea capitis. Initial histology revealed a lentigo maligna in situ subtype and the patient underwent surgical excision with split thickness skin graft. An invasive component was identified on histological examination of the entire lesion. This case highlights not only the rare entity of hair repigmentation as a sign of malignancy but also highlights past scalp radiotherapy as a possible risk factor in the development of melanoma.
Kelly et al. (Tue,) studied this question.