Duodeno-jejunal intussusception: an unusual manifestation of ampullary adenocarcinoma.

Duodeno-jejunal intussusception is highly unusual because of the retroperitoneal fixation of the duodenum, with only a limited number of cases documented in the literature. Furthermore, intussusception caused by a malignant ampullary lead point has not been reported previously. We present the case of a 58-year-old man who presented with obstructive jaundice for 8 months with no features of intestinal obstruction. Computed tomography imaging revealed dilation and deformation of the pancreaticobiliary tree due to duodenal intussusception. Intraoperative findings confirmed duodeno-jejunal intussusception with an ampullary mass acting as the lead point, which was confirmed to be adenocarcinoma upon pathological examination. The patient successfully underwent pylorus-preserving pancreaticoduodenectomy (Whipple procedure) with Child's reconstruction. Although duodenal intussusception is rarely encountered, clinicians must consider it in the differential diagnosis of unexplained biliary obstruction, even in the absence of intestinal obstruction features. A comprehensive diagnostic evaluation and tailored surgical approach are essential for optimal management.