A Case of Bronchial Leiomyoma with Complete Lower Lobe Atelectasis Treated by S⁶ Segmentectomy with Wedge Resection of the Bronchus

<p>Background. Pulmonary leiomyoma is a rare disease that account for only 0.04% of all lung tumors. It is classified into two types: bronchial and pulmonary parenchymal. Treatment options that preserve the respiratory function are preferred. However, the choice of treatment can be challenging, especially for bronchial leiomyomas that develop distally to the lobar bronchus. Case. The patient was a man in his 60s who presented with exertional dyspnea. Upon an examination, a nodule obstructing the left lower lobe bronchus was discovered, leading to his referral to our hospital. Bronchoscopy revealed that the tumor obstructed the left lower lobe bronchus inlet, and chest computed tomography revealed lower lobe atelectasis. A bronchoscopic biopsy did not lead to a definitive diagnosis; however, leiomyoma was suspected because smooth muscle code-like proliferation was observed, and positron emission tomography showed no accumulation. As it was determined that removal using a bronchoscope would be difficult, he was referred for thoracic surgery, and S⁶ segmentectomy with wedge resection of the lower lobe bronchus was performed. The resected specimen showed that a sessile tumor had developed from the root of B⁶, which occluded B⁶ and protruded into the lumen of the lower bronchial canal. The pathological diagnosis was a leiomyoma. The patient's dyspnea on exertion disappeared after surgery. Conclusion. Segmentectomy with wedge resection of the bronchus is a valuable surgical technique for preserving the respiratory function in leiomyoma arising at the bifurcation of segmental branches, especially when endoscopic treatment is not feasible.</p>