[Resection of Metastatic Lung Tumor with Abnormal Bronchial Bifurcation and Running Pulmonary Artery:Report of a Case].

The patient is a 69-year-old woman who underwent surgery for rectal cancer in January 202X. In July 202X+2, computed tomography (CT) revealed a nodule shadow with a maximum diameter of 4 mm in S1 of the right lung. After three months, the nodule increased in size. Based on the patient's history, a metastatic lung tumor was suspected, and the patient underwent surgical resection. Preoperative CT revealed the presence of B1 tracheobronchus and abnormal running of A1. B 1 was more centrally located than usual and branched directly from the trachea, whereas A1 branched from the main pulmonary artery trunk. S1 segmentectomy was performed for suspected metastatic lung tumor nodule in S1. Abnormal running of the pulmonary artery poses a risk of vascular injury during surgery. In the case of abnormal bronchial branching, the pulmonary vessels may be abnormal, and it is important to recognize such abnormalities using contrast-enhanced or three-dimensional CT preoperatively.