Killer in the Mirror: A Case of Duodenal Adenocarcinoma in a Patient with Situs Inversus Totalis

Situs inversus totalis is a rare congenital anomaly characterized by complete mirror-image reversal of thoracic and abdominal organs, occurring in approximately one in ten thousand live births. Intraabdominal surgeries in patients with this condition pose significant orientation challenges for the operating surgeon. Primary small bowel cancers, particularly duodenal adenocarcinomas, are also uncommon malignancies requiring complex surgical resection. We present a case of a 75-year-old female with situs inversus totalis who presented with dysphagia, nausea, vomiting, and weight loss. Upper gastrointestinal endoscopy revealed a proliferative growth at the peri-ampullary region, and biopsy confirmed adenocarcinoma. The patient underwent classical Whipple resection with curative intent. Despite the anatomical challenges and lack of advanced preoperative vascular imaging due to economic constraints, the surgery was completed successfully in 220 minutes with an estimated blood loss of only 300 milliliters. The right-handed surgeon operated from the right side of the patient, similar to normal anatomy, with careful identification of major vascular structures. Preoperative planning using mirror-image orientation and proper utilization of surgical assistants eliminated the need for surgeon position changes during the procedure. Histopathology confirmed periampullary duodenal adenocarcinoma with complete clearance. The patient had an uneventful postoperative course with early enteral feeding and was discharged on the seventh postoperative day. This case demonstrates that with proper preoperative orientation and surgical planning, complex pancreaticoduodenectomy can be performed safely and efficiently in patients with situs inversus totalis, achieving comparable outcomes to standard anatomy cases with reduced operative time and blood loss.