Application of the revised lung cancer staging system (IASLC Staging Project) to a cancer center population

Received 8 May 2008; received in revised form 13 October 2008; accepted 13 January 2009. published online 29 May 2009.

Objective

The International Association for the Study of Lung Cancer (IASLC) proposed a revision to the Union Internationale Contre le Cancer (UICC-6) staging system for non–small cell lung cancer. The goal of our study was to compare these systems in patients undergoing surgery for non–small cell lung cancer to determine whether one system is superior in staging operable disease.

Methods

Pathologic stages in 1154 patients undergoing complete resection over a 9-year period were analyzed. Patients were assigned a stage based on both IASLC and UICC-6 systems. We tested for statistically meaningful differences between the two staging systems using the Wilcoxon signed rank test and the permutation test.

Results

The IASLC system is more effective than the UICC-6 system at ordering and differentiating patients (P = .009). Application of the IASLC system resulted in 202 (17.5%) patients being reassigned to a different stage (P = .012), with the most common shifts occurring from IB to IIA and IIIB to IIIA. The 5-year and median survivals of the IASLC IIIA patients including those shifted from the UICC-6 IIIB were 37% and 35 months, respectively. Reclassifying UICC-6 IIIB to IASLC IIIA did not reduce survival for the newly characterized IIIA cohort.

Conclusion

Our data confirm that the proposed IASLC staging system is more effective at differentiating stage than the UICC-6 system. Reclassifying patients from UICC-6 IIIB to IASLC IIIA will shift some patients from a stage previously considered unresectable to a stage frequently offered surgical resection. Further study and validation of the IASLC system are warranted.

CTSNet classification: 10

Abbreviations and Abstracts: AJCC, American Joint Committee on Cancer, IASLC, International Association for the Study of Lung Cancer, NSCLC, non–small cell lung cancer, TNM, tumor, node, metastasis, UICC, Union Internationale Contre le Cancer, UTMDACC, University of Texas M. D. Anderson Cancer Center

a Department of Thoracic and Cardiovascular Surgery, The University of Texas M. D. Anderson Cancer Center, Houston, Tex

b Department of Biostatistics, The University of Texas M. D. Anderson Cancer Center, Houston, Tex

c Department of Radiology, The University of Texas M. D. Anderson Cancer Center, Houston, Tex

d Department of Radiation Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, Tex

e Department of Pathology, The University of Texas M. D. Anderson Cancer Center, Houston, Tex

f Department of Thoracic/Head and Neck Medical Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, Tex

Address for reprints: Jack A. Roth, MD, Department of Thoracic and Cardiovascular Surgery, The University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Blvd, Box 445, Houston, TX 77030-4095.

This work was partially supported by grants from the National Cancer Institute and the National Institute of Health: Specialized Program of Research Excellence (SPORE) in Lung Cancer (2P50-CA70907); by The University of Texas M. D. Anderson Cancer Center Support Core Grant (CA 16672); by a grant from the Tobacco Settlement Funds as appropriated by the Texas State Legislature (Project 8); by the W. M. Keck Foundation; and a sponsored research agreement with Introgen Therapeutics, Inc.

Read at the Eighty-eighth Annual Meeting of The American Association for Thoracic Surgery, San Diego, Calif, May 10–14, 2008.

PII: S0022-5223(09)00568-6

doi:10.1016/j.jtcvs.2009.01.033

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