Prognosis of lung cancer associated with cystic airspaces: A propensity score matching analysis

The association between the morphological characteristics and survival outcome of lung cancer associated with cystic airspaces (LCCAs) is unclear due to rarity of this disease. The current study attempted to compare the survival outcome between LCCAs and non-LCCAs and investigate the correlation between imaging features and prognosis of LCCA.Of 10,835 patients diagnosed with non-small cell lung carcinoma (NSCLC) between January 2015 and December 2016, 123 patients with LCCA were included. The non-LCCA group comprised 3136 patients with primary solitary adenocarcinoma or squamous cell lung cancer. Propensity score matching (PSM) was performed for age, sex, tumor size, tumor stage, and lymph node involvement in a 1:1 ratio between the LCCAs and non-LCCAs, and the correlation between radiological features and recurrence-free survival (RFS) was analyzed.The computed tomography (CT) lesion size was found to be higher in all LCCA subtypes, particularly in Type III (a cystic airspace with a mural nodule) and Type IV (mixed) LCCAs (3.09 and 3.65 cm, respectively), than in non-LCCAs (2 cm) after PSM. Three-year RFS in the LCCA group was higher than in the non-LCCA group (Type I- IV LCCAs: 100%, 84%, 77% and 83%, respectively vs. non-LCCAs: 77%). However, statistically significant difference was only found in comparison between LCCA Type I (thin-walled) and non-LCCA groups (P = 0.026). Type III lung cancer exhibited the worst survival among all four LCCA subtypes.The CT lesion size and pathologic tumor size varied significantly across LCCAs. Type I LCCAs exhibited better survival than non-LCCAs, whereas Type III LCCAs exhibited the worst survival rate among the four LCCA subtypes.