Abstract Background/Aim The standard treatment of stage I NSCLC is surgical resection with curative aim. Most of patients with stage I NSCLC are not recommended for adjuvant chemotherapy, however, up to 20% of patients eventually recur. This study aims to investigate the pathologic parameters including presence of driver mutations and PD-L1 expression in surgical specimens for postoperative recurrence and survival in stage I NSCLC after complete resection. Patients and Methods We analyzed data form the lung cancer registry at the Catholic Medical Center, Seoul, Republic of Korea. Eligible patients were those with histologically confirmed stage I NSCLC underwent surgical resection between January 2017 and December 2021. Clinicopathologic factors predicting treatment outcomes including disease-free survival (DFS) and overall survival (OS), were investigated. Results Disease recurred occurred in 56 patients (10.0%) of a total of 560 NSCLC patients underwent complete surgical resection. In univariate and multivariate analysis affecting DFS, age≥65, ECOG≥2, PD-L1 expression≥50% were significant factors. Age≥65 (p = 0.009), ECOG≥2 (p = 0.020), driver mutations (EGFR, ALK and ROS) (p = 0.025), PD-L1 expression≥50% (p = 0.001) were independently associated with poor OS, respectively. In addition, KM curve showed presence of driver mutations were significant risk factor for predicting death regardless of PD-L1 expression. Conclusion Our study shows driver mutations (+) and PD-L1 50% were associated with poor clinical outcome in in stage I NSCLC underwent surgical resection. These finding may help identify early stage NSCLC patients with a high risk of poor clinical outcome This abstract is funded by: None
C Yeo (2026) studied this question.