Case Report: Massive polypoid early Epstein-Barr virus-associated gastric carcinoma in a young immunocompromised host

Epstein-Barr virus-associated gastric carcinoma (EBVaGC) typically presents as a solitary lesion in older men. We describe a 24-year-old woman with chronic diarrhea and immunosuppression who was found to have multiple gastric lesions. Laboratory evaluation revealed active EBV replication (2.55 × 10⁵ copies/mL) and severe CD4 lymphopenia (180/μL). Esophagogastroduodenoscopy showed extensive gastric squamous metaplasia and multiple elevated lesions. The large antral mass was clinically suspected to represent advanced malignancy, and therefore, prompted distal gastrectomy, whereas the smaller fundic lesion was treated with endoscopic submucosal dissection. Histopathology unexpectedly revealed moderately-to-poorly differentiated adenocarcinomas with prominent lymphoid stroma at both sites. In situ hybridization confirmed EBV-encoded RNA positivity. Notably, both tumors were confined to the mucosa (pT1a), consistent with early gastric cancer. This case illustrates that EBVaGC may present as massive polypoid lesions mimicking advanced neoplasia in young, immunocompromised hosts. Careful integration of endoscopic and histopathological findings is essential for appropriate management.