Adenocarcinoma in situ detected on a thin-walled lung cavity: a case report

Background Cavitary lesions pathologically diagnosed as adenocarcinoma in situ (AIS) have been rarely reported. The examination of these type of lesions is necessary for a better understanding of the mechanisms underlying their formation and development of more efficient diagnostic and treatment strategies. Here, we present the case of a patient with cavitary lung carcinoma, diagnosed as AIS, who underwent partial resection. Case presentation A 72-year-old man presented with an abnormal shadow on chest radiography. Computed tomography findings showed a nodule in the right upper lobe, which was later diagnosed as an adenocarcinoma via transbronchial biopsy. A thin-walled cavity with partial thickening in the right lower lobe was also noted. We suspected that the thin-walled cavitary lesion was malignant, and performed wedge resection during a right upper lobectomy. AIS was diagnosed based on the histopathological findings of the thickened part of the thin-walled cavity. Conclusions This study highlights that, although rare, AIS may be observed in cavitary lung carcinoma cases, particularly in thin-walled lesions.