Adjuvant chemotherapy compared with observation in patients with T2aN0 stage IB lung adenocarcinoma

Po-Hsin Lee; Chun-Ju Chiang; Jeng-Sen Tseng; Zhe-Rong Zheng; Kun-Chieh Chen; Cheng-Hsiang Chu; Yen-Hsiang Huang; Kuo-Hsuan Hsu; Wen-Chung Lee; Tsung-Ying Yang; Tsang-Wu Liu; Jiun-Yi Hsia; Gee-Chen Chang

doi:10.3389/fonc.2023.1096683

Adjuvant chemotherapy compared with observation in patients with T2aN0 stage IB lung adenocarcinoma

Front Oncol. 2023 Feb 28:13:1096683. doi: 10.3389/fonc.2023.1096683. eCollection 2023.

Authors

Po-Hsin Lee^{1

2

3

4}, Chun-Ju Chiang^{5

6}, Jeng-Sen Tseng^{1

2

7

8}, Zhe-Rong Zheng^{9

10

11}, Kun-Chieh Chen^{9

10}, Cheng-Hsiang Chu^{9

10}, Yen-Hsiang Huang^{1

2

7}, Kuo-Hsuan Hsu¹², Wen-Chung Lee^{5

6}, Tsung-Ying Yang^{1

13}, Tsang-Wu Liu¹⁴, Jiun-Yi Hsia^{10

15}, Gee-Chen Chang^{7

9

10

11}

Affiliations

¹ Division of Chest Medicine, Department of Internal Medicine, Taichung Veterans General Hospital, Taichung, Taiwan.
² College of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan.
³ Ph.D. Program in Translational Medicine, National Chung Hsing University, Taichung, Taiwan.
⁴ Rong Hsing Research Center For Translational Medicine, National Chung Hsing University, Taichung, Taiwan.
⁵ Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taipei, Taiwan.
⁶ Taiwan Cancer Registry, Taipei, Taiwan.
⁷ Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan.
⁸ Department of Post-Baccalaureate Medicine, College of Medicine, National Chung Hsing University, Taichung, Taiwan.
⁹ Division of Pulmonary Medicine, Department of Internal Medicine, Chung Shan Medical University Hospital, Taichung, Taiwan.
¹⁰ School of Medicine, Chung Shan Medical University, Taichung, Taiwan.
¹¹ Institute of Medicine, Chung Shan Medical University, Taichung, Taiwan.
¹² Division of Critical Care and Respiratory Therapy, Department of Internal Medicine, Taichung Veterans General Hospital, Taichung, Taiwan.
¹³ Department of Life Sciences, National Chung Hsing University, Taichung, Taiwan.
¹⁴ National Institute of Cancer Research, National Health Research Institutes, Miaoli, Taiwan.
¹⁵ Division of Thoracic Surgery, Department of Surgery, Chung Shan Medical University Hospital, Taichung, Taiwan.

Abstract

Introduction: For patients with T2aN0 stage IB lung adenocarcinoma, benefits of adjuvant chemotherapy remain controversial. Here, we aimed to evaluate such benefits.

Methods: This retrospective cohort study was conducted on the database of the National Taiwan Cancer Registry. We analyzed patients with T2aN0 stage IB lung adenocarcinoma (re-classified by AJCC 8th edition) diagnosed during the period from January 2011 to December 2017. They were divided into two groups: (1) group 1: tumor <=3 cm with visceral pleural invasion (VPI); (2) group 2: tumor >3 cm, but <=4 cm. Overall survival (OS) and cancer specific survival (CSS) were evaluated. Risk factors for survival were determined.

Results: A total of 2,100 patients with T2aN0 stage IB lung adenocarcinoma (1,265 in group 1 and 835 in group 2) were enrolled for study. The proportions of patients receiving adjuvant chemotherapy in group 1 and 2 were 39.1% and 68.6%, respectively. Amongst group 1 patients, adjuvant chemotherapy was not an independent risk factor for OS and CSS. Amongst group 2 patients, high-grade histologic findings and receiving sublobar resection were two risk factors for poorer survival. Adjuvant chemotherapy was also associated with an OS (adjusted hazard ratio (aHR), 0.52; 95% confidence interval (CI), 0.38-0.72; P<0.001) and CSS (aHR, 0.54; 95% CI, 0.37-0.78; p=0.001) benefit regardless of the presence or absence of risk factors.

Conclusion: For patients with T2aN0 stage IB lung adenocarcinoma, adjuvant chemotherapy improved OS and CSS in those with tumors >3 cm, but <=4 cm.For patients with tumors <=3 cm with VPI, adjuvant chemotherapy had no survival benefit.

Keywords: T2aN0; adjuvant chemotherapy; early lung cancer; lung adenocarcinoma; stage IB.

Grants and funding

This study was funded by the Health Promotion Administration, Ministry of Health and Welfare, grant no. A1101009: Tobacco Health and Welfare Taxation. The funders had no role in study design, data collection and analysis, the decision to publish, or preparation of the manuscript.