# Cytomegalovirus Gastritis Induced by Immune Checkpoint Inhibitors Treatment in Lung Adenocarcinoma: A Case Report

## TL;DR

A lung cancer patient developed cytomegalovirus gastritis after treatment with immune checkpoint inhibitors, highlighting the need for careful diagnosis of stomach symptoms during such therapies.

## Contribution

This case report highlights the rare but important complication of cytomegalovirus gastritis in patients receiving immune checkpoint inhibitors.

## Key findings

- A patient with lung adenocarcinoma developed cytomegalovirus gastritis after pembrolizumab treatment.
- Endoscopic biopsy confirmed the diagnosis and antiviral treatment improved symptoms.
- Symptoms of cytomegalovirus gastritis are similar to immune-related gastritis, requiring biopsy for accurate diagnosis.

## Abstract

免疫检查点抑制剂（immune checkpoint inhibitors, ICIs）已广泛应用于实体肿瘤和血液系统肿瘤的治疗。ICIs引起的不良反应逐渐被重视。ICIs治疗后出现巨细胞病毒胃炎较为少见。本文结合文献复习报告1例晚期肺腺癌患者在使用帕博利珠单抗（Pembrolizumab）后出现反复上腹痛、呕吐，通过胃镜活检确诊为巨细胞病毒胃炎，患者接受抗病毒治疗后症状好转。在ICIs治疗过程中，需注意上腹痛症状的鉴别诊断，警惕巨细胞病毒胃炎。巨细胞病毒胃炎和免疫相关胃炎难以通过症状来鉴别，胃镜活检非常重要。

A: PET/CT showed that the entire gastric wall was significantly thickened with diffuse and unevenly increased metabolic uptake; B, C: Gastroscopy revealed that the entire gastric mucosa was bleeding and eroded, with a white coating on the surface; D: Gastroscopy showed that the mucosal lesions had significantly improved after antiviral treatment; E: Gastric mucosal biopsy revealed viral inclusion bodies in the cells (HE, ×400); F: In situ hybridization showed cytomegalovirus positive (×400). PET/CT: positron emission tomography/computed tomography; HE: hematoxylin-eosin.