Spindle cell/pleomorphic lipoma causing complete obstruction of the left main bronchus: a case report

Spindle cell/pleomorphic lipoma (SCPL) is a rare benign mesenchymal neoplasm that seldom arises in the tracheobronchial tree. We report the case of a 55-year-old man who presented with cough and intermittent blood-streaked sputum and was initially diagnosed with pneumonia. Chest computed tomography subsequently revealed a left hilar lesion with obstructive changes, raising suspicion of central-type lung cancer. Bronchoscopy demonstrated a smooth, polypoid lesion completely obstructing the left main bronchus. Fluorescence bronchoscopy and narrow-band imaging showed no prominent features suggestive of malignancy. An initial superficial biopsy was nondiagnostic, revealing inflammation, hemorrhage, and necrosis but no malignant cells. A larger specimen obtained by piecemeal bronchoscopic resection enabled definitive histopathological and immunohistochemical evaluation, leading to a diagnosis of SCPL. A second bronchoscopic procedure was performed to remove residual tumor and restore bronchial patency. The patient’s respiratory symptoms improved after treatment, and he remained symptom-free during follow-up. This case demonstrates that an obstructing endobronchial SCPL can closely mimic central lung cancer on imaging and may be missed by superficial biopsy. Adequate tissue sampling is essential for definitive diagnosis, and staged bronchoscopic resection can relieve airway obstruction in selected patients.