Postoperative radiotherapy option based on mediastinal lymph node reclassification for patients with pN2 non-small-cell lung cancer

  • J. Jin The 2nd Clinical Medical College of Zhejiang Chinese Medical University, Institute of Cancer and Basic Medicine
  • Y. Xu Zhejiang Cancer Hospital
  • X. Hu Institute of Cancer and Basic Medicine (ICBM), Chinese Academy of Science, Hangzhou, Zhejiang 310022, P.R. China; Department of Radiation Oncology, Cancer Hospital of the University of Chinese Academy of Sciences, Hangzhou, Zhejiang 310022, P.R. China; Department of Radiation Oncology, Zhejiang Cancer Hospital, Hangzhou, Zhejiang 310022, P.R. China.
  • M. Chen Institute of Cancer and Basic Medicine (ICBM), Chinese Academy of Science, Hangzhou, Zhejiang 310022, P.R. China; Department of Radiation Oncology, Cancer Hospital of the University of Chinese Academy of Sciences, Hangzhou, Zhejiang 310022, P.R. China; Department of Radiation Oncology, Zhejiang Cancer Hospital, Hangzhou, Zhejiang 310022, P.R. China; The 2nd Clinical Medical College of Zhejiang Chinese Medical University, Hangzhou, Zhejiang 310053, P.R. China.
  • M. Fang Institute of Cancer and Basic Medicine (ICBM), Chinese Academy of Science, Hangzhou, Zhejiang 310022, P.R. China; Department of Radiation Oncology, Cancer Hospital of the University of Chinese Academy of Sciences, Hangzhou, Zhejiang 310022, P.R. China; Department of Radiation Oncology, Zhejiang Cancer Hospital, Hangzhou, Zhejiang 310022, P.R. China.
  • Q. Hang Institute of Cancer and Basic Medicine (ICBM), Chinese Academy of Science, Hangzhou, Zhejiang 310022, P.R. China; Department of Radiation Oncology, Cancer Hospital of the University of Chinese Academy of Sciences, Hangzhou, Zhejiang 310022, P.R. China; Department of Radiation Oncology, Zhejiang Cancer Hospital, Hangzhou, Zhejiang 310022, P.R. China; The 2nd Clinical Medical College of Zhejiang Chinese Medical University, Hangzhou, Zhejiang 310053, P.R. China.
  • M. Chen Institute of Cancer and Basic Medicine (ICBM), Chinese Academy of Science, Hangzhou, Zhejiang 310022, P.R. China; Department of Radiation Oncology, Cancer Hospital of the University of Chinese Academy of Sciences, Hangzhou, Zhejiang 310022, P.R. China; Department of Radiation Oncology, Zhejiang Cancer Hospital, Hangzhou, Zhejiang 310022, P.R. China.
Keywords: non-small cell lung cancer, International Association for the Study of Lung Cancer, mediastinal lymph node skip metastasis, mediastinal lymph node station

Abstract

Background In this research, we used the mediastinal lymph node reclassification proposed by the International Association for the Study of Lung Cancer (iaslc) to screen for patients with pathologic N2 (pN2) non-small-cell lung cancer (nsclc) who might benefit from postoperative radiotherapy (port).

Methods The study enrolled 440 patients with pN2 nsclc who received complete surgical resection and allocated them to one of three groups: N2a1 (single-station skip mediastinal lymph node metastasis), N2a2 (single-station non-skip mediastinal lymph node metastasis), and N2b (multi-station mediastinal lymph node metastasis). Rates of local recurrence at first recurrence in patients receiving and not receiving port were compared using the chisquare test. Overall (os) and disease-free survival (dfs) were then compared using Kaplan–Meier survival analysis with log-rank test. In addition, the factors potentially influencing os and dfs were analyzed using univariate and multivariate Cox regression.

Results The rate of local recurrence for the N2a2 and N2b groups was significantly lower in patients receiving port (p = 0.044 and p = 0.043 respectively). The log-rank test revealed that, for the N2a1 group, differences in os and dfs were not statistically significant between the patients who did and did not receive port (p = 0.304 and p = 0.197 respectively). For the N2a2 group, os and dfs were markedly superior in patients who received port compared with those who did not (p = 0.001 and p = 0.014 respectively). For the N2b group, os was evidently better in patients who received port compared with those who did not (p = 0.025), but no statistically significant difference in dfs was observed (p = 0.134). Multivariate regression analysis revealed that, in the N2a1 group, port was significantly associated with poor os [hazard ratio (hr): 2.618; 95% confidence interval (ci): 1.185 to 5.785; p = 0.017]; in the N2a2 group, port was associated with improved os (hr: 0.481; 95% ci: 0.314 to 0.736; p = 0.001) and dfs (hr: 0.685; 95% ci: 0.479 to 0.980; p = 0.039).

Conclusions For patients with pN2 nsclc who receive complete resection, port might be beneficial only for patients with single-station non-skip metastasis (N2a2). Patients with single-station skip metastasis (N2a1) and multi-station metastasis (N2b) might not currently benefit from port.


Author Biographies

J. Jin, The 2nd Clinical Medical College of Zhejiang Chinese Medical University, Institute of Cancer and Basic Medicine

Chinese Academy of Science; Department of Radiation Oncology, Cancer Hospital of the University of Chinese Academy of Sciences; and Department of Radiation Oncology, Zhejiang Cancer Hospital

Y. Xu, Zhejiang Cancer Hospital

Institute of Cancer and Basic Medicine, Chinese Academy of Science; Department of Radiation Oncology, Cancer Hospital of the University of Chinese Academy of Sciences; and Department of Radiation Oncology

Published
2020-02-24
How to Cite
Jin, J., Xu, Y., Hu, X., Chen, M., Fang, M., Hang, Q., & Chen, M. (2020). Postoperative radiotherapy option based on mediastinal lymph node reclassification for patients with pN2 non-small-cell lung cancer. Current Oncology, 27(3). https://doi.org/10.3747/co.27.5899
Section
Radiation Oncology