Despite the recent advance of consolidation durvalumab in the treatment of unresectable stage III NSCLC, not every patient benefits from durvalumab and the predictive markers of response have been difficult to identify.

We performed a retrospective analysis of patients with unresectable stage III NSCLC treated with consolidation durvalumab after definitive chemoradiation from January 2018 to March 2020.

A total of 36 patients with unresectable stage III NSCLC were treated with consolidation durvalumab. Of these patients, 14 had tumor mutations in the ERBB family including 11 EGFR and 3 ERBB2. The ERBB2/EGFR tumor mutation cohort was more likely to be nonsmokers; otherwise, the two groups were similar in age, sex, programmed death-ligand 1 expression, and type of previous chemotherapy regimen. Patients in the ERBB2/EGFR cohort had a significantly shorter disease-free survival compared with the EGFR or ERBB2 wild-type cohort (7.5 mo versus not reached, p = 0.04).

Consolidation durvalumab seems to be less efficacious in patients with ERBB2/EGFR-mutant tumors. Future work should seek to evaluate this in the prospective setting and provide insight into the optimal treatment of ERBB2/EGFR-mutant stage III NSCLC.