Junmiao Wen and Donglai Chen
Donglai Chen, Chang Chen, Junmiao Wen and Yongbing Chen
Donglai Chen, Yiming Mao, Junmiao Wen, Jian Shu, Fei Ye, Yunlang She, Qifeng Ding, Li Shi, Tao Xue, Min Fan, Yongbing Chen and Chang Chen
Background: This study sought to determine the optimal number of examined lymph nodes (ELNs) and examined node stations (ENSs) in patients with radiologically pure-solid non–small cell lung cancer (NSCLC) who underwent lobectomy and ipsilateral lymphadenectomy by investigating the impact of ELNs and ENSs on accurate staging and long-term survival. Materials and Methods: Data from 6 institutions in China on resected clinical stage I–II (cI–II) NSCLCs presenting as pure-solid tumors were analyzed for the impact of ELNs and ENSs on nodal upstaging, stage migration, recurrence-free survival (RFS), and overall survival (OS). Correlations between different endpoints and ELNs or ENSs were fitted with a LOWESS smoother, and the structural break points were determined by Chow test. Results: Both ELNs and ENSs were identified as independent prognostic factors for OS (ENS hazard ratio [HR], 0.690; 95% CI, 0.597–0.797; P<.001; ELN HR, 0.950; 95% CI, 0.917–0.983; P=.004) and RFS (ENS HR, 0.859; 95% CI, 0.793–0.931; P<.001; ELN HR, 0.960; 95% CI, 0.942–0.962; P<.001), which were also associated with postoperative nodal upstaging (ENS odds ratio [OR], 1.057; 95% CI, 1.002–1.187; P=.004; ELN OR, 1.186; 95% CI, 1.148–1.226; P<.001). A greater number of ELNs and ENSs correlated with a higher accuracy of nodal staging and a lower probability of stage migration. Cut-point analysis revealed an optimal cutoff of 18 LNs and 6 node stations for stage cI–II pure-solid NSCLCs, which were validated in our multi-institutional cohort. Conclusions: Extensive examination of LNs and node stations seemed crucial to predicting accurate staging and survival outcomes. A threshold of 18 LNs and 6 node stations might be considered for evaluating the quality of LN examination in patients with stage cI–II radiologically pure-solid NSCLCs.