CT imaging in differentiating non-solid lung adenocarcinoma with cycstic airspaces: a clinical and diagnostic study

To investigate the correlation between clinical features, CT imaging manifestations and histopathology of cystic cavity-containing nodular lung adenocarcinomas, and to provide a basis for improving the diagnostic accuracy and therapeutic decision-making in this type of lung adenocarcinoma.

In total, 2146 patients with pathologically confirmed nodular lung adenocarcinoma in 3 hospitals in Anhui and Zhejiang were retrospectively analyzed from July 2017 to June 2023. The patients were divided into three groups according to their status of lung adenocarcinoma associated with cystic airspaces (LACA): the LACA0 group (no cystic airspaces, 1821 patients), the LACA1 group (cystic airspace diameter of < 5 mm, 208 patients), and the LACA2 group (cystic airspace diameter of ≥ 5 mm, 117 patients). The relationships between the patients' clinical data (e.g., sex, age, and smoking status), CT image characteristics (e.g., location, lobulation, and long-axis diameter), and postoperative histopathology were evaluated by univariate and multivariate analyses.

In the LACA2 group, 66(56.4%) patients were male, 57(48.7%) patients' lesions occurred in the lower lobe, 45(38.5%) patients' lesions were associated with pulmonary (e.g., emphysema/bullae, ventilation-perfusion imbalance)disease, 99(84.6%) patients had lobulation signs, and 50(42.8%) patients had postoperative histopathology findings of papillary, solid, or micropapillary adenocarcinoma. Multivariate logistic regression showed that sex, lobulation, long-axis diameter, location, and pulmonary disease were independent risk factors for LACA2.

When large cystic cavities (cystic cavity diameter ≥ 5 mm) are present in lung nodules of smoking male patients with lung disease, LACA subtypes should be comprehensively evaluated once the lesion shows signs of malignancy such as lobulation, in order to improve the diagnostic rate of the lesion and guide the clinic to develop an individualized treatment plan based on the imaging features.