Complete dissection of right paratracheal lymph nodes (stations 2R and 4R) is critical to improve the prognosis of lung cancer patients: A retrospective cohort study.

BACKGROUND: The optimal extent of mediastinal lymph node dissection is still under debate. This study aimed to investigate the prognostic impact of complete dissection of right paratracheal lymph nodes (LNs) in right-sided non-small cell lung cancer (NSCLC) and evaluate the potential patient population who will particularly benefit from right paratracheal node dissection (RPND). METHODS: Between January 2009 and December 2019, we retrospectively reviewed 2650 patients with primary right-sided NSCLC who underwent pulmonary surgery with lymphadenectomy in the Western China Lung Cancer Database. A total of 2447 patients received both 2R and 4R LNs dissection (complete RPND group), 162 patients received only 2R or 4R LNs dissection (incomplete RPND group), and 41 patients received neither 2R nor 4R LNs dissection (no RPND group). Overall survival (OS) was analyzed. RESULTS: The metastasis rates in stations 2R and 4R were 6.5% and 8.0%, respectively. In stage N2 patients, the frequency of involvement of stations 2R/4R was 74.8%. The complete RPND group had a significantly better survival than the incomplete and no RPND group (5-year OS, 79.5% vs. 72.7% vs. 65.5%; p < 0.001). In the multivariate analysis, status of RPND (incomplete RPND vs. complete RPND: HR 1.45, 95% CI: 1.10-1.90; p = 0.009; no RPND vs. complete RPND: HR 2.25, 95% CI: 1.37 to 3.69; p = 0.001), age, gender, tumor size, histological type, pTNM stage, pT stage, pN stage, and adjuvant treatment were independent factors for OS. CONCLUSIONS: Complete RPND brings survival benefits to patients with right-sided NSCLC. We suggest complete RPND as a standard procedure for patients with right-sided NSCLC.