Abstract Introduction Pulmonary bronchial gland cystadenoma is a rare benign endobronchial tumor that can obstruct central airways and closely mimic lung cancer on imaging. While most benign airway lesions exhibit low avidity on 18F-Fluorodeoxyglucose (FDG) PET/CT, cystadenomas may sometimes show significant uptake, thereby raising the risk of misdiagnosis. There have only been a few cases of FDG-avid mucous gland adenomas reported in the English-language literature, including two pulmonary mucous gland adenomas with high FDG uptake and two with low FDG uptake. Case Presentation We report the case of a 39-year-old asthmatic male with a long smoking history who developed intermittent hemoptysis, progressive dyspnea worse on his left side, and pleuritic left chest and back discomfort following a rollover motor-vehicle incident. A non-contrast chest CT identified an approximately 2-cm endobronchial mass in the distal left mainstem bronchus, resulting in significant narrowing of the left mainstem and upper-lobe airways, with near-occlusion of the lower-lobe bronchus and mild distal volume loss; a small peripheral nodule and a benign-appearing adrenal lesion were also observed. The endobronchial tumor showed significant FDG uptake on PET/CT; the Standardized uptake value (SUV) max was 8.8, but there were no avid lymph nodes or distant illness. Bronchoscopy with EBUS sampling of a mediastinal node was benign, and several endobronchial biopsies revealed a cystic lesion of small salivary/bronchial gland origin suspected to be papillary cystadenoma with supporting immunohistochemistry and no malignancy. Cardiothoracic surgery noted near-obliteration of the left lower-lobe bronchus at the left mainstem bifurcation and recommended pulmonary function testing and a nuclear perfusion scan to guide a likely left lower lobectomy, given the lesion’s critical airway location, which the patient currently awaits. Discussion This case underscores that an intensely FDG-avid obstructing endobronchial mass may represent a non-malignant pathology. Key takeaways for physicians include avoiding reliance solely on SUV, pursuing tissue diagnosis whenever possible, and integrating clinical presentation, bronchoscopic findings, and imaging before proceeding with oncologic surgery. Wider recognition of such cases may help prevent overtreatment and encourage airway-preserving, physiology-directed care where anatomical conditions permit. This abstract is funded by: None
Naseeb et al. (Fri,) studied this question.