Left lung combined segmentectomy for lung cancer with displaced left B¹⁺²

Congenital bronchial displacement with concomitant vascular anomalies complicates anatomical segmentectomy. We report a thoracoscopic combined S1 + 2 and S6 segmentectomy for early lung cancer in a patient with displaced left B1 + 2 and persistent left superior vena cava (PLSVC).

A 75-year-old man underwent chest computed tomography (CT) as part of a routine health examination, which revealed a 2.5-cm nodule in the left upper lobe. Computed tomography and bronchoscopy revealed a three‑branch carinal variation with left B¹⁺² arising dorsally from the left main bronchus; A¹⁺²and V¹⁺²coursed abnormally. The left lung was fissureless and PLSVC was present. After pulmonary rehabilitation his FEV1 improved from 1.20 L to 1.64 L. Given limited reserve, video‑assisted thoracoscopic combined segmentectomy (S¹⁺²+S⁶) was performed using a dorsal‑first hilar approach. Indocyanine green (ICG) fluorescence delineated the intersegmental planes, facilitating precise stapled transection. Final pathology revealed moderately to poorly differentiated squamous cell carcinoma, no visceral pleural invasion, intravascular tumor emboli, and spread through air spaces (STAS), with no perineural invasion and station 12 node 0/1. The postoperative course was uneventful without air leak; the patient was discharged on postoperative day 5. At 18‑month follow‑up, quality of life was good with no dyspnea or cough.

In rare left B¹⁺² displacement associated with vascular variants and PLSVC, 3D planning plus ICG mapping enables safe combined segmentectomy for pT1bN0M0 IA2 squamous cell carcinoma, balancing oncologic clearance with parenchymal preservation. The presence of STAS and vascular invasion underscores the need for generous margins and multidisciplinary surveillance.