Lung cancer associated with cystic airspaces: CT and pathological features

BACKGROUND: Lung cancer associated with cystic airspaces (LC-CAS) is a special type of lung cancer that is often misdiagnosed due to its similar imaging appearances to pulmonary bulla or pulmonary cyst. This study was designed to explore the imaging and pathological features of LC-CAS. METHODS: A retrospective analysis was performed on 35 LC-CAS patients treated in our center from January 2017 to January 2020. There were 23 men and 12 women aged 61.4±9.2 years, with a range of 44–78 years. All patients underwent chest computed tomography (CT), and the diagnoses were surgically and pathologically confirmed. RESULTS: The lesions were 0.5–3.0 cm (mean: 1.6±0.7 cm) in diameter. The CT signs of these lesions included lobulation sign (n=25), spicule sign (n=21), pleural indentation sign (n=22), vessel convergence sign (n=17), nodules on cystic wall (n=16), bronchial cut-off sign (n=15), uneven thickening of the cystic wall (n=10), and honeycombing (n=7). Postoperative pathological types included 30 cases of adenocarcinoma [which included 22 cases of invasive adenocarcinoma (IAC) and 8 cases of minimally invasive adenocarcinoma (MIA)], 4 cases of squamous cell carcinoma, and 1 case of adenosquamous carcinoma. CONCLUSIONS: LC-CAS has diverse CT signs. The most common pathological type of LC-CAS is adenocarcinoma.