Neoadjuvant Treatment Is Associated With Superior Outcomes in T4 Lung Cancers With Local Extension

Neoadjuvant chemoradiation is associated with improved survival of superior sulcus cancers, but little data exists regarding clinical T4 lung cancers with mediastinal invasion. We hypothesized that neoadjuvant treatment would be associated with improved survival in T4 lung cancer patients with mediastinal invasion.

Clinical T4-N0/1-M0 non-small cell lung cancers from 2006-2015 were identified in the National Cancer Database. Patients with T4 extension to mediastinal structures undergoing lobectomy, bilobectomy, or pneumonectomy were included. Neoadjuvant treatment was defined as preoperative chemotherapy and/or radiation. Patients receiving surgery >120 days after radiation were excluded. Study endpoints were pathologic margin status and overall survival. To adjust for heterogeneity, a 1:1 propensity match analysis was performed.

A total of 1101 patients with cT4N0/1M0 cancers were analyzed; 595 (54.0%) received primary surgery and 506 (46.0%) received neoadjuvant treatment. Neoadjuvant therapy was associated with fewer positive surgical margins (46 of 506 [9.3%] vs 186 of 595 [33.1%], P < .001). Multivariate analysis showed an association of neoadjuvant therapy with a lower rate of positive margin (odds ratio 0.220, P < .001). Overall survival was longer among patients receiving neoadjuvant treatment (65.9 vs 27.5 months, P < .001). Propensity matching identified 331 matched pairs of patients. Among these, positive margins were less likely after receiving neoadjuvant treatment (10.5% vs 31.3%, P < .001). Overall survival among the matched pairs was improved in those receiving neoadjuvant treatment (57.0 vs 27.5 months, P < .001).

In the NCDB, T4N0/1 mediastinal invasion patients who receive neoadjuvant treatment have decreased rates of positive surgical margins and improved overall survival. The use of neoadjuvant treatment should be considered in these patients.