Prognostic Significance of the Number of Metastatic pN2 Lymph Nodes in Stage IIIA-N2 Non-Small-Cell Lung Cancer After Curative Resection

Changhoon Yoo; Shinkyo Yoon; Dae Ho Lee; Seung-Il Park; Dong Kwan Kim; Yong-Hee Kim; Hyeong Ryul Kim; Se Hoon Choi; Woo Sung Kim; Chang-Min Choi; Se Jin Jang; Si Yeol Song; Su Ssan Kim; Eun Kyung Choi; Jae Cheol Lee; Cheolwon Suh; Jung-Shin Lee; Sang-We Kim

doi:10.1016/j.cllc.2015.04.004

Prognostic Significance of the Number of Metastatic pN2 Lymph Nodes in Stage IIIA-N2 Non-Small-Cell Lung Cancer After Curative Resection

Clin Lung Cancer. 2015 Nov;16(6):e203-12. doi: 10.1016/j.cllc.2015.04.004. Epub 2015 Apr 23.

Authors

Changhoon Yoo¹, Shinkyo Yoon¹, Dae Ho Lee¹, Seung-Il Park², Dong Kwan Kim², Yong-Hee Kim², Hyeong Ryul Kim², Se Hoon Choi², Woo Sung Kim³, Chang-Min Choi⁴, Se Jin Jang⁵, Si Yeol Song⁶, Su Ssan Kim⁶, Eun Kyung Choi⁶, Jae Cheol Lee¹, Cheolwon Suh¹, Jung-Shin Lee¹, Sang-We Kim⁷

Affiliations

¹ Department of Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
² Department of Thoracic Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
³ Department of Pulmonology and Critical Care Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
⁴ Department of Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea; Department of Pulmonology and Critical Care Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
⁵ Department of Pathology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
⁶ Department of Radiation Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
⁷ Department of Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea. Electronic address: swkim@amc.seoul.kr.

PMID: 25997733
DOI: 10.1016/j.cllc.2015.04.004

Abstract

Stage IIIA-N2 non-small cell lung cancer (NSCLC) shows prognostic heterogeneity. We investigated the prognostic relevance of the number of metastatic pN2 nodes in patients with IIIA-N2 NSCLC. The criteria for the number of pN2 used in this study were significantly associated with the survival outcomes after surgery and may improve the accuracy of prognostic prediction in this subgroup of patients.

Introduction: There have been controversies regarding the prognostic relevance of the number of positive N2 nodes in pathologic stage IIIA-N2 non-small-cell lung cancer (NSCLC). We examine prognosis of patients with pathologic stage IIIA-N2 with classifying the number of positive N2 nodes into subgroups.

Methods: From January 1997 to December 2004, 250 patients were diagnosed with pathologic stage IIIA-N2 disease. All patients underwent mediastinal lymph node dissection. After excluding 44 patients with preoperative chemotherapy, incomplete resection, and postsurgical mortality, 206 patients were included in the analysis. Patients were classified according to the number of positive N2 lymph nodes (N2a: 1 [n = 83], N2b: 2-4 [n = 82], N2c: ≥ 5 [n = 41]), and its correlation with survival outcomes were investigated.

Results: With a median follow-up of 96.3 months, 5-year disease-free survival (DFS) was 27.2% (95% confidence interval [CI], 21.6-33.7), and 5-year overall survival (OS) was 37.7% (95% CI, 31.5-44.7) in all patients. The number of metastatic N2 lymph nodes was associated with DFS (P < .001) and OS (P = .01). In the N2a, N2b, and N2c groups, 5-year DFS rates were 38%, 24%, and 5%, respectively, and 5-year OS rates were 47%, 35%, and 24%, respectively. In a multivariate analysis, the number of metastatic N2 lymph nodes was an independent prognostic factor for DFS and OS.

Conclusion: Stratification of patients according to the number of metastatic N2 lymph nodes may improve the accuracy of prognostic prediction among patients with curatively resected stage IIIA-N2 NSCLC.

Keywords: Adjuvant treatment; N2; Non–small-cell lung cancer; Prognosis; Stage IIIA.

MeSH terms

Adult
Aged
Aged, 80 and over
Carcinoma, Non-Small-Cell Lung / diagnosis*
Carcinoma, Non-Small-Cell Lung / mortality
Carcinoma, Non-Small-Cell Lung / surgery
Female
Follow-Up Studies
Humans
Lung Neoplasms / diagnosis*
Lung Neoplasms / mortality
Lung Neoplasms / surgery
Lymph Nodes / pathology*
Lymphatic Metastasis
Male
Middle Aged
Neoplasm Staging
Pneumonectomy
Prognosis
Retrospective Studies
Survival Analysis
Treatment Outcome