Comparison of National Comprehensive Cancer Network and American College of Surgeons Commission on Cancer Lymph Node Sampling Guidelines for Non-Small Cell Lung Cancer

Abstract

<h3>Purpose/Objective(s)</h3> Current guidelines conflict regarding adequate lymph node sampling during lung cancer surgery. The National Comprehensive Cancer Network (NCCN) guidelines recommend sampling at least 3 N2 and 1 N1 stations while the American College of Surgeons Commission on Cancer (CoC) guidelines recommend sampling at least 10 total lymph nodes. We sought to compare these guidelines in a cohort of Veterans with clinical stage I non-small cell lung cancer (NSCLC). <h3>Materials/Methods</h3> We performed a retrospective cohort study using a uniquely compiled dataset from the Veterans Health Administration (VHA) consisting of adults with clinical stage I NSCLC receiving surgery (2006-2016). We assembled a team of researchers who extracted lymph node sampling information from pathology reports and operative notes over a period in excess of 20 months. We defined sampling adequacy based on current guidelines from the NCCN (≥3 N2 + 1 N1 station) and CoC (≥10 lymph nodes). Our primary outcomes of interest were pathologic upstaging, disease-free survival, and overall survival. <h3>Results</h3> A total of 9575 patients were included in the current study. Of these, 3556 (37.1%) patients met NCCN guidelines and 3250 (33.9%) patients met CoC guidelines. Upstaging was observed in 1236 (12.9%) individuals. Adherence to either NCCN (adjusted odds ratio [aOR] 1.299, 95% CI 1.130-1.492) or CoC (aOR 1.637, 95% CI 1.425-1.881) guidelines was associated with higher likelihood of upstaging. With a median follow-up of 6.14 years, recurrence was observed in 2260 (23.6%) patients. While adherence to NCCN guidelines was associated with lower risk of recurrence (adjusted hazard ratio [aHR] 0.867, 95% CI 0.785-0.958), adherence to CoC guidelines was not associated with disease recurrence (aHR 0.928, 95% CI 0.839-1.028). Adherence to NCCN (aHR 0.932, 95% CI 0.874-0.994) or CoC (aHR 0.931, 95% CI 0.871-0.996) guidelines were associated with improved overall survival. <h3>Conclusion</h3> These data suggest that adherence to NCCN sampling guidelines may mitigate the risk of recurrence in clinical stage I NSCLC. Improving adherence to either guideline, however, may significantly improve long-term survival in patients with clinical stage I NSCLC undergoing surgical treatment.