A Unique Case of Invasive Adenocarcinoma of the Body and Tail of the Pancreas Presenting as Gastric Outlet Obstruction.

Advanced-stage pancreatic cancer can present as secondary gastric outlet obstruction (GOO), which is an extremely rare entity. Given the initial vague presentation of gastrointestinal symptoms, the diagnosis is often delayed, leading to high morbidity and mortality. We report the case of a 68-year-old male patient who presented with vomiting, epigastric pain, and weight loss. CT abdomen and pelvis showed a distended stomach with a transition point in the duodenum. Immediate stomach decompression through the nasogastric tube was performed. Upper endoscopy (EGD) revealed ischemic gastritis with gastric body necrosis. Biopsy of the duodenum revealed moderately differentiated invasive adenocarcinoma. Magnetic resonance cholangiopancreatography (MRCP) showed a 7-cm mass centered in the body and the tail of the pancreas, invading the duodenojejunal junction. No surgical or oncological management was indicated due to the advanced stage of the malignancy at the time of the diagnosis. Malignant GOO, even though rare, should be a part of the differential diagnosis in elderly patients with vague gastrointestinal symptoms.