The effect of adjuvant chemoradiotherapy on survival after R0 resection for stage III-N2 nonsmall cell lung cancer: A meta-analysis.

Abstract

Adjuvant chemotherapy is still the standard treatment for stage III-N2 nonsmall cell lung cancer after R0 resection, and it is still controversial whether conventional adjuvant radiotherapy is needed. We used meta-analysis to try to answer whether adjuvant postoperative chemoradiotherapy (POCRT) can bring survival benefits to patients with stage III-N2 nonsmall cell lung cancer after R0 resection. Up to June 25, 2021, the databases of PubMed, Embase, Cochrane Library, CNKI, and Wanfang were searched, and clinical studies on POCRT for stage III-N2 nonsmall cell lung cancer were included. RevMan5.4 software was used for meta-analysis. A total of 8959 patients were included in 5 randomized controlled trials and 17 retrospective studies. The results of the meta-analysis showed that POCRT could improve 3 and 5 years overall survival (OS) rate (OR = 1.52, 95%CI: 1.05-2.20; OR = 1.30, 95%CI: 1.16-1.46), 3 and 5 years disease-free survival (DFS) rate (OR = 1.34, 95%CI: 1.01-1.76; OR = 1.74, 95%CI: 1.43-2.12), and 5-year locoregional recurrence-free survival (LRFS) rate (OR = 2.69, 95%CI: 1.76-4.11) in patients with stage III-N2 nonsmall cell lung cancer compared with adjuvant postoperative chemotherapy (POCT) alone. But could not improve 5-year distant metastasis-free survival (DMFS) rate (OR = 1.14, 95%CI: 0.52-2.52). The results of subgroup analysis showed that postoperative sequential chemoradiotherapy could improve the 3 and 5 years OS rate (OR = 2.06, 95%CI: 1.22-3.46; OR = 1.39, 95%CI: 1.21-1.59). Three-dimensional conformal radiotherapy (3DCRT) or intensity-modulated radiotherapy (IMRT) can improve the 3 and 5 years OS rate (OR = 1.80, 95%CI: 1.09-2.99; OR = 1.31, 95%CI: 1.04-1.66). In addition, POCRT could improve the 3-year OS rate (OR = 1.88, 95%CI: 1.21-2.92) in patients with N2 single-station lymph node metastasis compared with POCT alone. Compared with POCT alone, adjuvant POCRT can significantly improve the overall survival rate of patients with NSCLC after R0 resection of stage III-N2, especially in patients with N2 single-station lymph node metastasis. Accurate radiotherapy techniques such as 3DCRT or IMRT are recommended, and postoperative sequential chemoradiotherapy is the best treatment mode.