Internal herniation beneath the external iliac vessels with deep vein thrombosis following pelvic lymphadenectomy: a rare cause of bowel obstruction

Internal hernias after pelvic lymphadenectomy are rare, but can cause small bowel obstruction and serious vascular complications. A woman in her early forties with prior endometrial cancer surgery presented with two weeks of progressive abdominal pain, distension, and right lower limb edema. Contrast-enhanced CT revealed herniation of small bowel loops through a peritoneal defect between the right external iliac artery (EIA) and the pelvic wall, with right external iliac vein compression and thrombosis. After preoperative inferior vena cava (IVC) filter placement, emergency laparotomy confirmed viable bowel herniated beneath the external iliac vessels. The hernia was reduced, the defect was closed with nonabsorbable sutures, and pelvic reconstruction was performed. The patient had an uneventful recovery. At three months, Doppler ultrasonography showed partial recanalization of the right external iliac vein without recurrence. Surgeons should be aware of this rare complication. Early recognition and multidisciplinary management are crucial for favorable outcomes.