Robot-assisted distal gastrectomy with lymph node dissection for gastric cancer in a patient with situs inversus partialis: a case report with video file

BACKGROUND Situs inversus is a rare congenital condition that is currently classified into two types: complete situs inversus (situs inversus totalis, SIT) and partial situs inversus (situs inversus partialis, SIP). In SIP patients, some organs are inverted and others are in their expected position, and individual patient variation in organ position increases surgical difficulty. Several surgeons have performed laparoscopic or robotic surgeries in situs inversus patients, but almost all were SIT patients. We report the first case, to our knowledge, of an SIP patient with gastric cancer who was successfully treated by robot-assisted distal gastrectomy (RADG) with lymph node dissection. CASE PRESENTATION A 64-year-old woman diagnosed with early gastric cancer on the posterior midbody of the stomach was referred to our hospital for treatment. Computed tomography showed levocardia and inverted abdominal organs without enlarged lymph nodes or distant metastases. Polysplenia syndrome, intestinal malrotation, and left-sided gallbladder were also detected. RADG with D1+ lymph node dissection and Billroth I reconstruction (delta-shaped anastomosis) were performed using robotics. Hepatopathy caused by a liver retractor and pancreatic fistula were identified during the postoperative course, and the latter was classified as grade II based on Clavien-Dindo classification. The patient was discharged 18 days after the operation. CONCLUSIONS Preoperative three-dimensional imaging is beneficial, and anatomical organ identification should be routinely performed, especially in SIP patients. We consider RADG a therapeutic option in SIP patients.