Outcomes of patients with technically resectable stage III non-small cell lung cancer treated with concurrent chemoradiation followed by durvalumab consolidation.

e20013 Background: Patients with early stage non-small cell lung cancer (NSCLC) benefit from surgical resection when feasible. The PACIFIC trial showed that patients with advanced stage III NSCLC with unresectable tumors have improved overall survival (OS) and progression-free survival (PFS) when treated with definitive concurrent chemoradiation (CCRT) followed by durvalumab (D) consolidation. In patients with potentially resectable disease, neoadjuvant chemoimmunotherapy (chemoIO) now has demonstrated survival benefit in stage IIIa and select IIIb (AJCC 8th Ed.) disease, but has not been compared to CCRT+D. Therefore, we chose to retrospectively analyze patients with stage IIIA and B NSCLC who would have been potentially eligible for neoadjuvant chemIO but were treated with CCRT+D between 2017 and 2023 with the intent to analyze outcomes of those patients with potentially resectable disease treated with CCRT+D. Methods: We developed a cohort of patients with stage IIIA or B NSCLC treated with CCRT+D consolidation using the University of Minnesota Thoracic Oncology and Immunooncology registries. Charts were reviewed to identify patients without actionable ALK or EGFR alterations whose tumors were classified as resectable, potentially resectable, or unclear resectability according to the EORTC Lung Cancer Group Initiative (Dingemans A-M, et al., ECLC 2023). Patients must have received CCRT and at least one dose of D between 1/1/2017 and 9/22/23. We calculated PFS and OS in our cohort from the time of initiation of chemotherapy. The University of Minnesota IRB approved the protocol (IRB ID: STUDY00020781). Results: 82 patients were included in the analysis. For patients with stage IIIA disease: median age at diagnosis was 69 years, median PFS was 12 months, and median OS was 35 months. For patients with stage IIIB disease: median age at diagnosis was 67 years, median PFS was 8 months, and median OS was 29 months. Conclusions: These findings suggest CCRT+D consolidation is a reasonable option for patients with potentially resectable stage IIIA or IIIB NSCLC when surgery is not pursued due to comorbidities or personal preference. Comparison of outcomes with patients treated with neoadjuvant or perioperative chemoimmunotherapy and surgical resection is limited by differences in performance status and comorbidities. Outcomes of patients in our cohort. Characteristic Stage IIIA (N=62) 1 Stage IIIB (N=20) 1 p-value 2 Squamous cell carcinomaAdenocarcinomaAdenosquamous 29 (47%)31 (50%)2 (3.2%) 12 (60%)8 (40%)0 (0%) 0.7 ECOG 0ECOG 1ECOG 2ECOG 3ECOG unknown 17 (30%)34 (60%)6 (11%)0 (0%)5 6 (32%)8 (42%)3 (16%)2 (11%)1 0.094 Age at diagnosis 69 (13) 67 (16) 0.8 OS 35 (24) 29 (35) >0.9 PFSunknown 12 (16)33 8 (9)12 0.6 1 n (%); Median (IQR). 2 Fisher's exact test; Wilcoxon rank sum test.