Optimal Lymph Nodes Examination and Adjuvant Chemotherapy for Stage I Lung Cancer
Menée en Chine à partir des données du registre national des cancers portant sur 65 438 patients atteints d'un cancer du poumon de stade I traité par chirurgie entre 2006 et 2014, puis validée sur une cohorte de 117 112 patients complémentaires, cette étude détermine le nombre optimal de ganglions lymphatiques à analyser pour stadifier avec précision la maladie et prédire la survie, puis évalue le rôle d'une chimiothérapie adjuvante chez les patients dont le nombre de ganglions analysés est en dessous du seuil optimal
Purpose : To determine the optimal number of lymph nodes (LNs) examined and role of adjuvant chemotherapy in stage I lung cancer.
Methods : The National Cancer Database was queried for surgically-treated patients with pathologic stage I lung cancer between 2006 and 2014 (n=65,438). The optimal LN numbers were determined in the multivariate Cox model, and were further validated in clinical stage I cohort (n=117,112) in terms of nodal upstaging and prognostic stratification. The role of adjuvant chemotherapy in patients with suboptimal staging (examined LN number fewer than the optimum) was evaluated in each T stage.
Results : The number of LNs examined correlated with tumor size (p<0.001). There were increasing survival benefits with each additional LN examined, up to 8, 9, 10, and 11 nodes for patients with T1a, T1b, T1c, and T2a, respectively. Validation from clinical cohort showed that the threshold of 8-11 LNs was an independent predictor of nodal upstaging (OR, 1.706; 95%CI, 1.608-1.779) and survival outcome (HR, 0.890; 95%CI, 0.865-0.916). After propensity matching, adjuvant chemotherapy was associated with improved survival in T2a patients having suboptimal staging (HR: 0.841; 95%CI, 0.714-0.990), but not in T1a to T1c.
Conclusion : LN evaluation was important for accurate staging and adequate treatment, and examinations of an increasing number of nodes for progressively higher T components (i.e., 8, 9, 10, and 11 nodes for T1a, T1b, T1c, and T2a tumors, respectively) seemed crucial to predict upstaging and survival outcomes. Adjuvant chemotherapy might be beneficial to T2a patients having suboptimal nodal staging.
Journal of Thoracic Oncology , résumé, 2018