Benign Emptying After Right Lower Lobectomy Mimicking a Bronchopleural Fistula.

Bronchopleural fistula (BPF) is a serious and potentially fatal postoperative complication after pulmonary resection. Benign emptying of the postpneumonectomy space (BEPS) is a rare, self-limiting condition characterized by a sudden reduction in pleural fluid volume without evidence of fistula formation, observed after pneumonectomy. To date, BEPS-like conditions following lobectomy have not been reported. Because the clinical and radiological manifestations of BEPS overlap significantly with those of BPF, distinguishing between them is challenging. We present an unusual case of a BEPS-like phenomenon that developed after a right lower lobectomy and initially mimicked a BPF both clinically and radiographically. A 77-year-old man with a history of interstitial pneumonia and prostate cancer presented with right lower lobe adenocarcinoma. He underwent video-assisted thoracoscopic right lower lobectomy with lymph node dissection and was discharged without complications. Five weeks after surgery, he developed increased sputum production and mild dyspnea. Chest radiography revealed a reduction in the right pleural effusion, raising a strong suspicion of BPF. Exploratory thoracoscopy showed a well-healed bronchial stump without air leakage on saline irrigation or indocyanine green dye testing. These results supported the diagnosis of a BEPS-like condition. The patient's symptoms resolved spontaneously without therapeutic intervention, and follow-up imaging confirmed stable lung expansion and no recurrence at five months after exploratory thoracoscopy. This case highlights that a self-limiting BEPS-like phenomenon may occur even after lobectomy and can closely mimic BPF in presentation. Because the consequences of overlooking BPF are life-threatening, a cautious diagnostic approach integrating clinical evaluation, imaging, bronchoscopy, and, when indicated, surgical exploration is imperative before adopting conservative management. Awareness of this condition is crucial for thoracic surgeons to avoid unnecessary invasive interventions while ensuring prompt management of true BPF when present.