mutation ( ) in patients (pts) with stage IV non-small cell lung cancer (NSCLC) is associated with inferior survival and poor response to immune checkpoint inhibitors (ICI). The significance of in stage III NSCLC pts treated with concurrent chemoradiation (CCRT) with or without consolidation ICI is unknown.

Stage III NSCLC patients who received CCRT and had known mutational status were included in this retrospective study. The data on the pts were collected from 4 cancer institutions. A cohort of pts with wild type ( ) from the University of Iowa served as a comparison group. Patient demographics and clinical characteristics were collected. Cox regression models were used to explore the effect of mutation on survival.

75 pts with stage III NSCLC who had known mutational status were identified. 16/75 (21%) had . 5/16 with did not receive CCRT so they were excluded from the analysis. The clinical and demographic characteristics for the 11 and 59 pts were not statistically different ( ): mean age: 57 64 yrs, non-squamous histology: 8/11 (73%) 37/59 (63%), mutation: 3/11 (27%) 11/59 (19%), mutation: 6/11 (55%) 15/59 (25%), PD-L1 ≥50%: 1/8 (13%) 10/32 (31%), and consolidation ICI 6/11 (55%) 17/59 (29%). Regarding the 6 pts who received ICI (4 pembrolizumab, 2 durvalumab), the median number of ICI infusions was 8 (range, 3-17) 6 (range, 1-25) in the 17 pts with who received ICI (durvalumab). After adjusting for performance status and cancer stage, multivariable analysis showed that progression free survival (PFS) for the pts was significantly worse than pts (HR =2.25; 95% CI, 1.03-4.88, P=0.04), whereas overall survival (OS) showed no significant difference for patients (HR 1.47, 95% CI, 0.49-4.38, P=0.49).

In stage III NSCLC patients who received CCRT, was associated with worse PFS compared to . Larger studies are needed to further explore the prognostic implications of in stage III NSCLC and whether ICI impacts survival for this subgroup.