Neoadjuvant vs Adjuvant Chemoimmunotherapy for Stage II-IIIB Non-Small Cell Lung Cancer

Abstract

Background: In patients with resectable non-small cell lung cancer (NSCLC), recent trials demonstrate survival benefit of chemoimmunotherapy over chemotherapy alone in both the neoadjuvant and adjuvant settings. To date, there is no direct comparison between neoadjuvant and adjuvant protocols. We compared neoadjuvant vs adjuvant chemoimmunotherapy for resectable stage II-IIIB NSCLC.

Methods: We queried the National Cancer Database for patients who had undergone an operation for stage II-IIIB NSCLC and who had received neoadjuvant or adjuvant chemoimmunotherapy between 2015 and 2020. We used inverse probability weighting to adjust for confounding variables and used Kaplan-Meier survival curves and Cox regression to explore the relationship between treatment groups and overall survival (OS) at 3 years postoperatively.

Results: The inverse probability-weighted cohort represented 2119 weighted patient cases (neoadjuvant, 1034; adjuvant, 1085). Kaplan-Meier analysis demonstrated a significant OS benefit for neoadjuvant chemoimmunotherapy compared with adjuvant chemoimmunotherapy in the weighted cohort (3-year OS: 77% [95% CI, 71%-83%] vs 68% [95% CI, 64%-72%]; P = .035). On adjusted Cox regression, neoadjuvant chemoimmunotherapy was associated with a significant OS benefit (hazard ratio, 0.70; 95% CI, 0.50-0.96; P = .027). Among patients for whom pathologic stage data were available, 25% of patients receiving neoadjuvant chemoimmunotherapy had a pathologic complete response, with an additional 32.5% being downstaged.

Conclusions: Neoadjuvant chemoimmunotherapy confers a significant OS benefit over adjuvant chemoimmunotherapy for patients with resectable stage II-IIIB NSCLC. Although randomized trials are needed to confirm our findings, strong consideration should be given to administering neoadjuvant chemoimmunotherapy to patients who are predetermined to receive systemic treatment.