Pulmonary Myelolipoma in NSCLC with EML4- ALK Fusion: A Case Report and Literature Review

Abstract

Pulmonary or bronchial myelolipomas are rare, and no cases of genetic testing have been clinically reported, which limits research on their pathogenesis and the scientific basis of diagnosis and treatment. A 52-year-old Asian male presented with a two-week history of paroxysmal cough and blood-streaked sputum. The patient reported no additional symptoms and had no history of smoking. A chest computed tomography (CT) scan conducted two years prior revealed a 10 mm × 18 mm nodule in the right lower lung, which had increased to 32 mm × 16 mm on the current scan. In addition, an enlarged lymph node measuring 18 mm × 10 mm was observed in the right lower pulmonary hilum, along with a pulmonary bulla. A whole-body 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) scan demonstrated increased metabolic activity in both the mass and the enlarged lymph node. A thoracoscopic right lower lobectomy was performed, and the pulmonary bulla was removed concurrently. Pathological examination confirmed non-small cell lung carcinoma (NSCLC) in the mass, while the tissue surrounding the pulmonary bulla revealed mixed components, including bone, adipose, and hematopoietic tissues. Postoperative tumor mutation testing identified an EML4-ALK fusion gene variant. The patient recovered well following surgery, and a follow-up chest X-ray showed a resolution of atelectasis in the right lower lung. Adjuvant therapy with alectinib is planned.