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Author Spotlight: A Model to Study the Systemic and Local Dynamics of CD8+ T Cells During LN Metastasis
Published on: January 26, 2024
Prognostic impact of N1 lymph node micrometastasis in T1-2a Non-small cell Lung Cancer
Hiroyasu Koga1, Tetsukan Woo2, Mai Matsumura3
1Department of Surgery, Yokohama City University School of Medicine, Yokohama, Japan; Department of Thoracic Surgery, National Hospital Organization Yokohama Medical Center, Yokohama, Japan.
Objectives:
Lymph node micrometastasis, defined as tumor deposits <2 mm, has been proposed as an adverse prognostic factor in early-stage non-small cell lung cancer (NSCLC), but its clinical significance remains unclear. This study aimed to evaluate the prognostic impact of N1 micrometastasis in patients with T1-2a NSCLC.
Patients And Methods:
We retrospectively analyzed patients with pathologically confirmed T1-2a NSCLC who underwent complete resection-including lobectomy or more extensive procedures-with systematic lymph node dissection between 2000 and 2015. N1 micrometastasis was identified by cytokeratin immunohistochemistry and quantified using digital slide analysis.
Results:
Among 617 patients, 550 had no lymph node metastasis, 22 had N1 micrometastasis, and 45 had N1 macrometastasis. In univariate analysis, patients with N1 micrometastasis had significantly worse recurrence-free survival (RFS) and overall survival (OS) compared with those without lymph node involvement (5-year RFS: 53.3 % vs. 85.1 %, P < 0.001; 5-year OS: 61.5 % vs. 87.0 %, P = 0.007). Multivariate analysis identified N1 micrometastasis as an independent adverse prognostic factor for RFS (HR 2.589, 95 % CI 1.388-4.829, P = 0.003) and OS (HR 2.179, 95 % CI 1.052-4.513, P = 0.036). Furthermore, stabilized inverse probability of treatment weighting (IPTW)-adjusted analysis confirmed significantly worse RFS (HR 2.992, 95 % CI 1.276-7.018, P = 0.012), whereas the difference in OS did not reach statistical significance (HR 2.207, 95 % CI 0.855-5.698, P = 0.102).
Conclusions:
N1 lymph node micrometastasis is a significant negative prognostic factor for RFS in T1-2a NSCLC. These findings support further prospective studies to validate its role in guiding treatment decisions for early-stage NSCLC.
Short Abstract:
We retrospectively analyzed patients with pathologically confirmed T1-2a non-small cell lung cancer (NSCLC) who underwent complete resection with systematic lymph node dissection. Multivariate and stabilized inverse probability of treatment weighting (IPTW)-adjusted analyses identified N1 lymph node micrometastasis as a significant adverse prognostic factor for postoperative recurrence-free survival (RFS).