Abstract
OBJECTIVE: To evaluate the effect of postoperative adjuvant immune checkpoint inhibitor (ICI) therapy on survival outcomes in resectable non-small cell lung cancer (NSCLC) patients who received neoadjuvant chemoimmunotherapy. METHODS: A retrospective cohort study was conducted at Zhongshan Hospital, Fudan University, from January 2019 to June 2024, including resectable NSCLC patients treated with neoadjuvant chemotherapy combined with ICIs. Pathological responses were assessed, and event-free survival (EFS) and overall survival (OS) were compared between patients who received postoperative adjuvant ICI therapy and those who did not. RESULTS: Among the 186 patients included, 106 received adjuvant ICI therapy, while 80 did not. No significant differences in EFS or OS were observed between the two groups in patients who achieved pathological complete response (pCR) or major pathological response (MPR) (EFS: p = 0.282, OS: p = 0.330). In contrast, patients who did not achieve pCR or MPR experienced a significant improvement in EFS with adjuvant ICI therapy (p = 0.004). An AI-based decision tree model developed to predict the need for postoperative adjuvant immunotherapy demonstrated strong performance, with an accuracy of 85% and an area under the curve (AUC) of 0.82. Key predictors identified by the model included pathological response, age, clinical stage, and PD-L1 expression. CONCLUSIONS: Postoperative adjuvant ICI therapy significantly improves EFS in resectable NSCLC patients, especially in those without pCR or MPR. However, its effect on OS remains uncertain. These findings highlight the importance of personalized treatment strategies, with adjuvant ICI offering greater benefits for patients with incomplete pathological responses.