A Comparison of the Currently Used Nodal Stage Classification with the Number of Metastatic Lymph Nodes and the Number of Metastatic Lymph Node Stations for Non-Small Cell Lung Cancer; Which of These Is the Best Prognostic Factor?^[*]

Abstract

Objectives We aimed to compare the currently used nodal staging system (pN) with the number of metastatic lymph node (LN) stations (sN) and the number of metastatic LNs (nN) on survival in patients with NSCLC.

Methods Between 2010 and 2017, 1038 patients resected for NSCLC were analyzed. We performed three-different stratifications of LN status assessment: pN-category (pN0, pN1 and pN2); sN-category (sN0, sN1; one station metastasis, sN2; two-three stations metastases, and sN3; ≥ 4 stations metastasis); nN-category (nN0, nN1; one-three LNs metastasis, nN2; four-six Lns metastasis, and nN3; ≥ 7 LNs metastasis).

Results Five-year survival rate was 70.1% for N0 in all classifications. It was 54.3% for pN1, and 26.4% for pN2 (p < 0.0001). Five-year survival rates for N1, N2, and N3 categories were 54.1%, 42.4% and 16.1% according to sN, and 51.4%, 36.1%, and 7.9% according to nN, respectively (p < 0.0001). In multivariate analysis, sN and nN were independent risk factors such as pN (p < 0.0001). Hazard ratios versus N0 for N1, N2, and N3 were more significant for sN and nN than pN (1.597, 2.176, and, 3.883 for sN, 1.645, 2.658, and, 4.118 for nN, and 1.576, 3.222 for pN, respectively). When the subcategories of sN and nN were divided into pN1 and pN2 subgroups, the anatomic location of the LN involvement lost importance as tumor burden and tumor spreading increased.

Conclusion The number of metastatic LN stations and the number of metastatic LNs are better prognostic factors than currently used nodal classification in NSCLC.

Zusammenfassung

Ziele Die Anzahl der metastasierten LN-Stationen und die Anzahl der metastasierten LNs sind bessere prognostische Faktoren als die derzeit verwendete nodale Klassifikation in NSCLC.

Methoden Zwischen 2010 und 2017 wurden 1038 resezierte Patienten für NSCLC analysiert. Wir haben 3 verschiedene Schichten für die LN-Zustandsbewertung durchgeführt: pN-Kategorie (pN0, pN1 und pN2); sN-Kategorie (sN0, sN1; 1. Station der Metastase, sN2; die 2. und 3. Station der Metastasen und sN3; ≥ 4. Station der Metastasen); die nN-Kategorie (nN0, nN1; 3 LNs Metastase, nN2; Metastasen in 4 – 6 LNs und nN3; Metastasen in ≥ 7 LNs).

Ergebnisse Die 5-Jahres-Überlebensrate betrug 70,1% für N0 in allen Klassifikationen. Sie lag bei 54,3% für pN1 und 26,4% für pN2 (p < 0,0001). Die 5-Jahres-Überlebensrate für die Kategorien N1, N2 und N3 betrug 54,1%, 42,4% und 16,1% nach sN und 51,4%, 36,1% und 7,9% nach nN (p < 0,0001). In der multivariaten Analyse waren sN und nN unabhängige Risikofaktoren wie pN (p < 0,0001). Die Gefahrenverhältnisse gegenüber N0 für N1, N2 und N3 waren für sN und nN signifikanter als für pN (1,597, 2,176 und 3,883 für sN; 1,645, 2,658 und 4,118 für nN bzw. 1,576, 3,222 für pN). Bei der Einteilung der Unterkategorien von sN und nN in den pN1- und pN2-Subgruppen verloren die anatomische Lage der LN-Beteiligung mit zunehmender Tumorbelastung und Tumorausbreitung an Bedeutung.

Fazit Die Anzahl der metastasierten LN-Stationen und die Anzahl der metastasierten LNs sind bessere prognostische Faktoren als die derzeit verwendete nodale Klassifikation in NSCLC.

Key words

non-small cell lung cancer - number of metastatic lymph node stations - number of metastatic lymph nodes - prognosis - staging

Schlüsselwörter

nicht kleinzelliger Lungenkrebs - Anzahl der metastasierten Lymphknotenstationen - Anzahl metastatischer Lymphknoten - Prognose - Staging des Lungenkarzinoms

^* Presentation: Presented at the Oral Presentation Session of the 26th European Conference on General Thoracic Surgery, Ljubljana/Slovenia/2018; winner of the ESTS/the Deutsche Gesellschaft für Thoraxchirurgie Travel Grant Award

Publication History

Article published online:
24 October 2019

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