An Observational Population Level Study of Neoadjuvant Chemoimmunotherapy for Resectable Non-Small-Cell Lung Cancer

Neoadjuvant chemoimmunotherapy (NCIT) is being increasingly used in the treatment of resectable and early-stage NSCLC based on recent randomized controlled trials. The real-world effectiveness of this approach remains uncertain. We aimed to evaluate pathological response, treatment completion, surgical outcomes, and rates of relapse among patients with resectable NSCLC treated with NCIT in routine practice.

Demographic, clinical, treatment, and outcome variables were captured for 64 patients with stage II-III NSCLC treated with NCIT at cancer centers across Alberta, Canada, using a province-wide registry. Median follow-up was 7 months. Neoadjuvant Nivolumab combined with platinum-doublet chemotherapy administered every 3 weeks for up to 3 cycles. Primary endpoints were complete pathological response (pCR), major pathological response (mPR), and treatment completion rates. Secondary endpoints included adverse events, surgical complications, and disease recurrence events.

Of 64 patients, 57 (89.1%) completed NCIT, and 55 (85.9%, 95% CI, 75.4%-92.4%) underwent surgery. Pathological responses included mPR in 28 (44%, 95% CI, 32.3%-55.9%) and pCR in 19 (30%, 95% CI, 19.9%-41.8%). All but one patient who proceeded to surgery achieved an R0 resection. Adverse events occurred in 45 (71.4%) patients with 10 (15.6%) experiencing CTCAE grade ≥3 events. Nine patients (14.1%, 95% CI, 24.6%-92.4%) did not undergo surgery, most often due to disease progression rendering the disease unresectable. Seven patients (12.9%, 95% CI, 5.4%-20.9%) relapsed postoperatively, none of whom had experienced mPR (P = .001).

In this real-world cohort, NCIT for resectable NSCLC achieved pCR and mPR rates comparable to pivotal clinical trials, with manageable toxicity and favorable surgical outcomes. These findings suggest no major efficacy-effectiveness gap, although longer follow-up is needed to assess survival outcomes.