Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2024 Nov 27;24(1):1460.
doi: 10.1186/s12885-024-13139-z.

Validation of IASLC 9th edition TNM classification for lung cancer: focus on N descriptor

Joung Woo Son #  1 , Joonseok Lee #  1 , Jae Hyun Jeon  2 , Sukki Cho  1 , Woohyun Jung  1 , Beatrice Chia-Hui Shih  1 , Kwhanmien Kim  1 , Sanghoon Jheon  1
Affiliations

Validation of IASLC 9th edition TNM classification for lung cancer: focus on N descriptor

Joung Woo Son et al. BMC Cancer. .

Abstract

Background: We externally validated the proposed 9th edition of the TNM staging classification with our institution's prospectively collected data and compared it to the 8th edition for overall survival (OS) and freedom from recurrence (FFR).

Methods: A retrospective analysis was conducted of 4029 cases of stage I-III non-small cell lung cancer that underwent surgical treatment from January 2004 to December 2020. Survival was compared using Kaplan-Meier curves and multivariable Cox regression analysis. The concordance index (C-index), Alkaike information criterion (AIC), and R2 were used to assess the discriminatory ability.

Results: In the 9th edition, the N2 category (n = 352) was subdivided into N2a (n = 256, 72.7%) and N2b (n = 96, 27.3%). The TNM stage changes were as follows: (1) IIB to IIA, 151 cases (26.0%); (2) IIIA to IIB, 52 cases (11.5%); (3) IIIB to IIIA, 57 cases (61.3%); (4) IIIA to IIIB, 56 cases (12.4%). The survival curves of the proposed 9th edition demonstrated similar patterns to those of the 8th edition, but with a greater discriminative ability for OS and FFR. Subdividing N2 into N2a and N2b refined prognosis prediction. The C-index, AIC, and R2 demonstrated improved values in the proposed 9th edition compared to the 8th edition.

Conclusions: The proposed 9th edition of the TNM staging classification for lung cancer showed favorable prognostic validity and better discrimination ability than the 8th edition.

Keywords: External validation; Nodal stage; Non-small cell lung cancer; Prognostic validity; TNM classification.

PubMed Disclaimer

Conflict of interest statement

Declarations. Ethics approval and consent to participate: This study was approved by the Institutional Review Board of Seoul National University Bundang Hospital. (IRB Number: B-2401-875-102, Approved date: 2023 − 1218). The requirement for informed consent was waived because of the retrospective study design. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests.

Figures

Fig. 1
Fig. 1
Cross table plots of 8th and proposed 9th edition TNM staging classification (A) and N staging classification (B)
Fig. 2
Fig. 2
Survival curves of overall survival (A) and freedom-from recurrence (B) based on the 8th and proposed 9th edition of the TNM staging classification
Fig. 3
Fig. 3
Survival curves of overall survival (A) and freedom-from recurrence (B) between the segmentectomy and the lobectomy group in patients diagnosed with pathologic stage IA
Fig. 4
Fig. 4
Survival curves of overall survival (A) and freedom-from recurrence (B) based on the 8th and proposed 9th edition of the N staging classification
Fig. 5
Fig. 5
Survival curves of freedom-from recurrence (A) and overall survival (B) according to subdivision of N2a group as N2a1 and N2a2
See this image and copyright information in PMC

References

    1. Adjei AA. Lung cancer worldwide. J Thorac Oncol. 2019;14(6):956. - PubMed
    1. Bülzebruck H, Drings P, Kayser K, et al. Classification of lung cancer: first experiences with the new TNM classification (4th edition). Eur Respir J. 1991;4(10):1197–206. - PubMed
    1. Goldstraw P, Chansky K, Crowley J, et al. The IASLC lung cancer staging project: proposals for revision of the TNM stage groupings in the forthcoming (eighth) edition of the TNM classification for lung cancer. J Thorac Oncol. 2016;11(1):39–51. 10.1016/j.jtho.2015.09.009 - PubMed
    1. Asamura H, Nishimura KK, Giroux DJ, et al. IASLC lung cancer staging project: the new database to inform revisions in the ninth edition of the TNM classification of lung cancer. J Thorac Oncol. 2023;18(5):564–75. 10.1016/j.jtho.2023.01.088 - PubMed
    1. Chen K, Chen H, Yang F, Sui X, Li X, Wang J. Validation of the eighth edition of the TNM staging system for lung cancer in 2043 surgically treated patients with non–small-cell lung cancer. Clin Lung Cancer. 2017;18(6):e457–66. 10.1016/j.cllc.2017.04.001 - PubMed

Publication types

LinkOut - more resources