Anisakid larva mimicking a gastric subepithelial lesion: an unexpected histopathological diagnosis

Anisakidosis is a fish-borne zoonosis caused by the ingestion of live infective anisakid nematode larvae present in raw or undercooked seafood. Cases presenting as a gastric subepithelial lesion with histopathological confirmation are rare. Here we describe a 71-year-old asymptomatic woman whose screening esophagogastroduodenoscopy showed a subepithelial lesion measuring <10 mm in the gastric body, covered by intact mucosa and suspected to be a leiomyoma. Bite-on-bite biopsy unexpectedly revealed anisakid nematode larvae. The patient reported habitual sushi consumption. This case highlights the value of clinicopathological correlation and clinician awareness of anisakidosis in nonendemic urban settings amid rising global raw fish consumption.