Am J Dermatopathol 2016 Dec;38(12):e159-e162
*Department of Anatomical Pathology, PathWest, QEII Medical Centre, Perth, Western Australia, Australia; †School of Pathology and Laboratory Medicine, University of Western Australia, Perth, Western Australia, Australia; ‡Department of Medical Oncology, Sir Charles Gairdner Hospital, Perth, Western Australia, Australia; §School of Medicine and Pharmacology, University of Western Australia, Perth, Western Australia, Australia; and ¶Margaret River Surgery, Margaret River, Western Australia, Australia.
Malignant melanoma is a common source of cutaneous metastases and can occasionally adopt a histological appearance which mimics a primary melanocytic lesion, either benign or malignant. The authors describe a case of new cutaneous deposits of metastatic melanoma in a 70-year-old woman with a prominent admixed lymphocytic infiltrate, imparting a striking resemblance to a halo nevus. The authors believe this appearance was a direct reflection of treatment with pembrolizumab, a humanized antibody against the immune checkpoint inhibitor programmed death-1. Read More