A retroperitoneal-first laparoscopic technique is promising for bile duct resection in pancreaticobiliary maljunction, improving surgical outcomes.

• Operative time was 480 minutes, with 210 minutes for the retroperitoneal approach and only 40 ml blood loss.
• Postoperative recovery was smooth; the patient was discharged on day 14 and remains recurrence-free after 3 years post-chemotherapy.

This technique offers enhanced visualization and stability, essential for challenging bile duct surgeries.

• It may be particularly beneficial for safe transection above the pancreatobiliary junction and improving lymphadenectomy.