Comparing the benefits of chemoradiotherapy and chemotherapy for resectable stage III A/N2 non-small cell lung cancer: a meta-analysis

BACKGROUND: Induction chemotherapy has been shown to improve survival of patients with stage III A/N2 (T1–3, N2, M0) non-small cell lung cancer (NSCLC), followed by resection, but the benefits of neoadjuvant radiotherapy still remain controversial. METHODS: PubMed, Embase, and Cochrane library databases were searched for relevant randomized controlled trials (RCTs) comparing the outcomes of induction chemoradiotherapy over induction chemotherapy, in patients with resectable stage IIIA/N2 NSCLC. Odds ratios (ORs) with corresponding 95% confidence intervals (95% CIs) were calculated using random- or fixed-effects model, and heterogeneity was assessed using I(2) test. Publication bias was examined by funnel plots analysis. RESULTS: A total of three RCTs met the inclusion criteria of our meta-analysis. The pooled results demonstrated that, in comparison to induction chemotherapy, induction chemoradiotherapy has a significant benefit in tumor response, mediastinal downstaging, and pathological complete response of mediastinal lymph nodes. In addition, no more peri-intervention mortality was detected in patients from chemoradiotherapy group, and a higher number of patients from this group had R0 resection. However, our results did not show any difference between overall survival and progression-free survival after 2, 4, and 6 years of follow-ups, in patients undergoing radiation therapy vs. induction chemotherapy. CONCLUSION: Preoperative chemoradiotherapy, as compared to induction chemotherapy alone, is associated with similar peri-intervention mortality, a greater tumor response, mediastinal nodule downstaging, and rate of R0 resection, but does not improve survival of resectable stage IIIA/N2 NSCLC patients.