Abstract
BACKGROUND: Small-cell lung cancer (SCLC) is a highly aggressive form of lung cancer. The emergence of chemoimmunotherapy has changed the mode of SCLC treatment. However, in limited-stage SCLC (LS-SCLC), the effectiveness and safety of chemoimmunotherapy in the neoadjuvant setting for LS-SCLC are not well-established. To address this gap, we conducted a study to evaluate neoadjuvant chemoimmunotherapy in LS-SCLC. METHODS: A retrospective study was conducted on patients from Beijing Chest Hospital, Capital Medical University, who underwent etoposide-based chemotherapy with programmed death-ligand 1/programmed death 1 (PD-L1/PD-1) inhibitors (neoCIT group) or without (neoCT group) prior to surgery for LS-SCLC between April 2019 and March 2023. The primary endpoints were to evaluate the major pathological response (MPR) and the pathological complete response (pCR). Secondary endpoints comprised event-free survival (EFS), overall survival (OS), and safety. RESULTS: A total of 31 patients with stage IIB-IIIB LS-SCLC were included, comprising 16 cases in the neoCIT group and 15 patients in the neoCT group. A pCR was observed in eight cases [50.0%; 95% confidence interval (CI): 28.0 to 72.0] within the neoCIT group, compared to one patient (6.7%; 95% CI: 0.3 to 29.8) in the neoCT group (odds ratio, 14.00; 95% CI: 1.71 to 164.20; P=0.02). An MPR was observed in 14 cases (87.5%; 95% CI: 64.0 to 97.8) within the neoCIT group, while three patients (20.0%; 95% CI: 7.0 to 45.2) were noted in the neoCT group, yielding an odds ratio of 28.00 (95% CI: 4.23 to 150.50; P<0.001). The median EFS was not achieved with neoCIT, while it was 19.0 months with neoCT (hazard ratio, 0.15; 95% CI: 0.04 to 0.62). The median OS was not reached for neoCIT, while it was 39.0 months for neoCT (hazard ratio, 0.23; 95% CI: 0.06 to 0.95). Grade 3 or 4 adverse events were observed in five patients in the neoCIT group (30.0%) and five in the control group (33.3%). CONCLUSIONS: Our study underscores the potential of neoadjuvant chemoimmunotherapy in resectable SCLC patients. The significant improvements in pCR, MPR, EFS, and OS compared to neoadjuvant chemotherapy alone offer a promising outlook for the future management of LS-SCLC.