Recurrent lentigo maligna invading a skin graft successfully treated with Mohs' micrographic surgery

Abstract

Lentigo maligna (LM) is a pigmented lesion occurring on sun-exposed skin that may become lentigo maligna melanoma (LMM). The tumor can behave in an aggressive fashion, causing significant cosmetic disfigurement, often extending significantly further than the clinical margin. Complete surgical excision is the treatment of choice. We describe a 74-year-old woman with a large LM of the left cheek, upper and lower eyelids, and preauricular skin that had recurred twice. The tumor was removed using Mohs' micrographic surgery (MMS) with rush permanent sections and was found to infiltrate extensively the split-thickness skin graft that had been placed five years earlier. LM can invade and replace a skin graft. Although destructive modalities and conventional surgery are recommended by some authors, MMS offers the greatest likelihood of cure, the ability to examine nearly 100 percent of the surgical margins, and maximal tissue sparing. Complete excision of LM at its earliest recognition may prevent invasive LMM and will limit cosmetic disfigurement.