Nicole Chang, Yoni Hirsch, Krisztian Nemeth, Susan Pei
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引用次数: 0
Abstract
Immune checkpoint inhibitors (ICIs) targeting programmed cell death protein 1 (PD-1), programmed cell death ligand 1 (PD-L1), and cytotoxic lymphocyte-associated antigen-4 (CTLA-4) have revolutionized cancer treatment but are associated with immune-related adverse events, particularly cutaneous toxicities. We report a rare case of pembrolizumab-exacerbated pigmented purpuric dermatosis (PPD) in a 77-year-old male with a history of metastatic non-small cell lung cancer. His rash, initially confined to the lower extremities, worsened and became widespread to involve the trunk after pembrolizumab initiation. Histopathology showed perivascular lymphocytic infiltrate with extravasated erythrocytes without vasculitis, compatible with PPD; however, due to some lymphocyte atypia and exocytosis, together with the clinically widespread lesions, there was initial concern for PPD-like mycosis fungoides (MF). Subsequent T-cell receptor gene rearrangement studies revealed no monoclonal lymphoid population, and the later resolution of the rash with treatments typical for PPD did not support MF. This represents only the second reported case of ICI-associated PPD and highlights a potential diagnostic pitfall with histopathology and clinical presentation mimicking PPD-like MF. Our case contributes to the expanding spectrum of ICI-related cutaneous reactions and underscores the importance of recognizing inflammatory dermatoses with atypical histopathologic features for dermatologists and dermatopathologists.
期刊介绍:
Journal of Cutaneous Pathology publishes manuscripts broadly relevant to diseases of the skin and mucosae, with the aims of advancing scientific knowledge regarding dermatopathology and enhancing the communication between clinical practitioners and research scientists. Original scientific manuscripts on diagnostic and experimental cutaneous pathology are especially desirable. Timely, pertinent review articles also will be given high priority. Manuscripts based on light, fluorescence, and electron microscopy, histochemistry, immunology, molecular biology, and genetics, as well as allied sciences, are all welcome, provided their principal focus is on cutaneous pathology. Publication time will be kept as short as possible, ensuring that articles will be quickly available to all interested in this speciality.