Mesenchymal cystic hamartoma of the lung mimicking simple pulmonary aspergilloma: a case report

Abstract

Abstract Background Mesenchymal cystic hamartoma is a rare pulmonary neoplasm, which occasionally presents with severe symptoms such as pneumothorax or hemothorax, and shows favorable outcomes following surgical resection. It presents as solitary or multiple cystic lesions and requires differentiation from cystic malignancies, lymphangiomyomatosis, and cystic adenomatoid malformation. Case presentation We encountered a 46-year-old woman with mesenchymal cystic hamartoma mimicking simple pulmonary aspergilloma on diagnostic imaging. Chest computed tomography showed a cystic lesion 1.6 cm in diameter, with an intracavitary nodule. Surgical resection proved neither fungus nor malignancy, and the final pathological diagnosis of mesenchymal cystic hamartoma was made. Conclusions Mesenchymal cystic hamartoma might show aspergilloma-like features on diagnostic imaging, in addition to the differential diagnosis of lung cancer.