In a Chinese single-institution study reported in the Journal of Clinical Oncology, Wang et al found that station 4L lymph node (LN) dissection was associated with improved outcome in patients with primary cancer of the left lung.
The retrospective analysis included 657 patients with primary left lung cancer who underwent resection between January 2005 and December 2009 at a single center. Only patients who underwent pulmonary resection (lobectomy or pneumonectomy) with lymphadenectomy were included. Of these, 139 patients underwent 4L LN dissection and 518 patients did not. Propensity score weighting analysis was employed to account for differences between the 2 groups in pTNM stage (P = .002), pN stage (P = .034), and tumor size (P = .028). Study outcome measures were disease-free survival and overall survival.
Metastasis Rate and Survival Outcomes
The metastasis rate of station 4L was 20.9%, compared with 14.0% for station 7 (P = .048) and 9.8% for station 9 (P < .001). In univariate analysis, association with station 4L metastasis was observed for most other LN station metastases; in multivariate analysis, only station 10 LN metastasis was independently associated with 4L LN metastasis (odds ratio = 0.253, P = .001).
For the 4L LN dissection group vs the group without 4L LN dissection, 5-year disease-free survival was 54.8% vs 42.7% (P = .0376) and 5-year overall survival was 58.9% vs 47.2% (P = .0200). In multivariate analysis, 4L LN dissection remained a significant independent factor in improved disease-free survival (hazard ratio [HR] = 1.502, P = .002) and overall survival (HR = 1.585, P = .001). Propensity score weighting analysis confirmed the benefit of 4L LN dissection in disease-free survival (P = .0014) and overall survival (P < .001).
The investigators concluded, “Station 4L LN involvement is not rare in left lung cancer, and dissection of the 4L LN station seems to be associated with a more favorable prognosis as compared with those who did not undergo this dissection.”
Zhen-Fa Zhang, MD, of Tianjin Medical University Cancer Institute and Hospital, is the corresponding author for the Journal of Clinical Oncology article.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.