The number of involved nodal stations has the potential to provide a more accurate prognosis in patients with resected non-small cell lung cancer (NSCLC), according to the results of a recent study published in the journal CHEST.
Researchers retrospectively reviewed medical records of patients with NSCLC undergoing surgical resection. The prognosis performance of the number of involved nodal station classification was compared with the location-based nodal classification using Kaplan-Meier and multivariate Cox analysis.
A total of 4011 patients with NSCLC undergoing surgical resection were identified and included in the study analysis. Four prognostically different subgroups were chosen according to the number of involved nodal stations: 1) nS0 (none positive), 2) nS1 (1 involved station), 3) nS2 (2 involved stations), and 4) nS≥3 (3 or more). A total of 2762 patients were categorized as nS0, 558 patients as nS1, 309 patients as nS2, and 382 patients as nS≥3. When these categories were compared, the number of involved nodal stations was an independent prognostic factor of both disease-free and overall survival.
Patients who were categorized as location-based N1 or N2 stage could be further divided into 3 prognostically different subgroups according to nodal station classification. However, there were no significant differences in disease-free and overall survival between N1 and N2 patients when staged in the same nodal station category. According to the decision curve analysis, the nodal station classification tended to have a higher predictive capability compared with the location-based nodal classification.
“The proposed nS classification in this study may provide a more accurate prognosis for patients with completely resected NSCLC,” the study authors wrote. “Thus, the nS is worth considering with respect to further revisions of the nodal classification in the forthcoming ninth edition of the TNM [tumor, node, metastasis] staging system.”
Xu L, Su H, She Y, et al. Which N descriptor is more predictive of prognosis in resected non-small cell lung cancer: the number of involved nodal stations versus the location-based pathological N stage? CHEST. Published online December 19, 2020. doi:10.1016/j.chest.2020.12.012