Robotic Segmentectomy in a Patient with a Displaced Left Upper Division Bronchus and Fused Fissure.

Introduction: In thoracic surgery, anatomical anomalies and a fused fissure can cause inaccurate intraoperative recognition of anatomy and lead to accidental injury of pulmonary vessels and bronchi that should be preserved. A displaced left upper division bronchus (B¹⁺²⁺³), also known as a left eparterial bronchus, is a rare anomaly that can present in combination with abnormal pulmonary arteries positioning and lobulation. Herein, we report a case of lung cancer in S¹⁺² of the left fused lung that was successfully resected by robotic left upper division segmentectomy following a detailed preoperative simulation using 3-dimensional computed tomography.

Case presentation: A female octogenarian presented for the treatment of simultaneous bilateral lung cancer. Three months after surgery for right lung cancer, a surgery for left lung cancer was performed. Preoperative computed tomography identified several broncho-arterial anomalies and a completely fused fissure, including a displaced left upper division bronchus and a pulmonary artery running anteriorly to the left main bronchus, similar to those in the right lung. Robotic left upper division segmentectomy with lymph node dissection was performed using a "hilum first, fissure last" approach with fine dissection of the hilar structures and minimal bleeding. The postoperative course was uneventful.

Conclusions: Preoperative simulation and robotic-assisted thoracoscopic surgery enabled the safe and precise anatomical pulmonary segmentectomy for a patient with lung cancer, despite several bronchial and arterial anomalies, including a displaced left upper division bronchus.