Lymphocytic gastritis induced by pembrolizumab in a patient with metastatic melanoma

• Published in: Melanoma research Vol. 28; no. 6; p. 645
• Main Authors: Yip, Raymond H L, Lee, Lawrence H, Schaeffer, David F, Horst, Basil A, Yang, Hui-Min
• Format: Journal Article
• Language: English
• Published: England 01.12.2018
• Subjects: Adult; Antibodies, Monoclonal, Humanized - adverse effects; Antineoplastic Agents, Immunological - adverse effects; Gastritis - chemically induced; Humans; Immunotherapy - methods; Male; Melanoma - complications; Melanoma - drug therapy; Melanoma - pathology; Skin Neoplasms - complications; Skin Neoplasms - drug therapy; Skin Neoplasms - pathology
• ISSN: 1473-5636
• DOI: 10.1097/CMR.0000000000000502

Immune checkpoint inhibitors such as programmed cell death-1 inhibitor pembrolizumab have been shown to be effective in metastatic malignancies such as advanced melanoma. Immune-related adverse effects on multiple organs have been described, such as colitis, skin rash, and hypothyroidism. We present the case of a 44-year-old man with advanced melanoma and recurrent lung metastases who developed symptoms of dyspepsia and gastroesophageal reflux disease after 1 month of therapy with pembrolizumab. Gastric biopsy showed histologic features consistent with lymphocytic gastritis, which was absent on a biopsy 2 months before initiation of therapy. Lymphocytic infiltrates likely secondary to increased autoimmunity after use of immunotherapy have been observed in the colon; however, such histologic findings in the upper gastrointestinal tract have yet to be described. Here, we present a case of lymphocytic gastritis in a patient treated with pembrolizumab, suggesting a new manifestation of toxicity.