Enblock Resection of the Right Middle Lobe and Right Anterior Segment of the Upper Lobe for Middle Lobe Lung Cancer with Displaced B3

There have been rare reports of B3 displacement from the right middle lobe (RML) bronchus. We report a case of thoracoscopic resection of the RML and anterior segment (S3) for RML lung cancer with B3 displacement from the RML bronchus. A 70-year-old woman was admitted to our hospital due to an abnormal shadow detected on chest radiography. Chest computed tomography (CT) revealed a middle lobe tumor and a displaced B3 bronchus originating from the RML. The tumor measured 30 mm in diameter; further, a transbronchial biopsy confirmed the adenocarcinoma diagnosis. We successfully performed a complete thoracoscopic resection of the RML and anterior segment of the right upper lobe. Given the limited knowledge of the lymphatic flow around the displaced bronchus, we opted for a reasonable approach to lymph node dissection. Preoperative assessments, including chest CT, bronchoscopy, and three-dimensional reconstructed CT scans, can facilitate preoperative bronchial and pulmonary vasculature identification.