Unveiling the Masquerade: Early Gastric Cancer Mimicking Advanced Disease with Ectopic Pancreas Intrusion.

Gastric cancer is a significant health concern worldwide, and its diagnosis and management are of paramount importance. Ectopic pancreas (EP) refers to an embryological abnormality where healthy pancreatic tissue develops without anatomical, vascular, or neural communication with the normal pancreas. We report the case of a patient whose initial endoscopic evaluation suggested early gastric cancer, but computed tomography scan (CT scan) and endoscopic ultrasound (EUS) indicated a locally advanced tumor. After a collegial evaluation and in accordance with the main diagnostic suspect, the patient underwent laparoscopic subtotal gastrectomy with D2 lymphadenectomy and Roux-en-Y reconstruction. Histopathological analysis post-surgery revealed an early-stage T1b gastric cancer coexisting with ectopic pancreatic tissue. The presence of ectopic pancreas in the stomach is a rare but noteworthy entity, often presenting a diagnostic challenge due to its varied clinical and histological features. Our case report aims to shed light on this condition by presenting a detailed clinical case, including clinical presentation, imaging findings, histological features, and treatment outcomes. Always improving our endoscopic practice and seeking an early diagnosis is the way to avoid post-staging surprises and misdiagnoses.