A Case of Pulmonary Sialadenoma Papilliferum Presenting with Finger-in-glove Sign

A 61-year-old woman was referred to our hospital after a chest computed tomography scan revealed a mass lesion in the right lower lobe. The mass had been growing for 4 years, with a branching shadow at its periphery showing a finger-in-glove sign. A forceps biopsy was performed using a bronchoscope, which was suspicious for papilloma; however, malignancy could not be ruled out. Thoracoscopic surgery was subsequently performed, confirming the diagnosis of sialadenoma papilliferum (SP). SP is a rare benign tumor of the salivary glands, with recent reports focusing on its pathological and immunological characteristics. Although SP can also occur in the bronchi, reports on pulmonary SP are limited, and many of its characteristics remain unknown. This case provides clinically useful information for managing pulmonary SP.