Adjuvant immunotherapy does not improve survival in non-small cell lung cancer with major/complete pathologic response after induction immunotherapy.

BACKGROUND

In patients with resectable non-small cell lung cancer (NSCLC), immune checkpoint inhibitor (ICI)-based regimens in both neoadjuvant and perioperative settings have demonstrated a survival benefit. However, no previous study has compared the efficacy between pure neoadjuvant and perioperative approaches, especially in patients who achieve a substantial pathologic response.

METHODS

In this retrospective study, patients with clinical stage II-IIIB NSCLC who achieved either a major pathologic response (MPR) or pathologic complete response (pCR) after induction ICI plus chemotherapy, followed by resection, between 2019 and 2023 were identified from multicenter databases. Inverse probability of treatment weighting-adjusted Cox regression was performed to compare disease-free survival (DFS) and overall survival (OS) between patients who received ICIs postoperatively and those who did not.

RESULTS

One hundred thirty-six patients who achieved pCR and 72 patients who achieved MPR were enrolled. Three-quarters of them had squamous cell cancer. The inverse probability-weighted cohort represented 208 weighted patient cases (adjuvant ICI group, n = 117; control group, n = 91). The weighted DFS and OS rates did not differ between the adjuvant ICI group and the control group (3-year DFS rate: 90.2% vs 93.2%; hazard ratio [HR], 2.47; 95% confidence interval [CI], 0.74-8.22; 3-year OS rate: 89.1% vs 93.9%; HR, 2.44; 95% CI, 0.71-8.34). Adverse events during the postoperative ICI treatment were found in 19 of 120 patients (15.8%) and led to adjuvant ICI termination in 18 patients (15.0%).

CONCLUSIONS

Adjuvant ICI does not improve survival in NSCLC patients who achieve pCR/MPR following neoadjuvant immunochemotherapy. A de-escalation strategy could be considered, given the adverse events associated with postoperative ICI treatment.