右B3分岐異常を有する肺癌症例に対する右S3＋4＋5切除

Right S3＋4＋5 Resection for Lung Cancer with Displaced B3

気管支の分岐異常は肺血管の走行異常と比較するとまれであり，中でも右B3分岐異常は全気管支分岐異常の中でも少ない1）．当院で経験した，右B3分岐異常を有する肺癌症例に対し右S3＋4＋5切除を施行した症例について報告する．

A 68-year-old man was referred to our hospital due to an abnormal shadow on chest X-ray film. Chest computed tomography showed a tumor in the right middle lobe. The tumor was 41 mm in size and invaded S3. Preoperative bronchoscopy revealed that right B1, B2, and B3 were branched independently, and B3 was branched from the middle lobe bronchus. A trans-bronchial biopsy was performed and primary lung squamous cell carcinoma was diagnosed （cT2bN0M0, stageⅡA）. Although minor fissure was not observed, S3＋4＋5 resection was performed successfully by dividing pulmonary blood vessels and bronchus before dividing incomplete lobulation （bronchus-first method）. The bronchus-first method is useful to avoid not only post-operative air leakage but also accidental cutting of the displaced bronchus by dividing incomplete lobulation frequently associated with bronchial branching abnormalities.