Objective: The preferred neoadjuvant treatment for gastroesophageal junction (GEJ) adenocarcinoma is still matter of debate. We conducted a meta-analysis to assess the different impact of neoadjuvant combined chemotherapy and radiotherapy (CTRT) versus chemotherapy (CT) alone.
Methods: A comprehensive search was performed in EMBASE, PubMed, and Cochrane Library databases from inception to 30th June 2018. Studies comparing survival of patients who underwent CTRT or CT alone before surgery for GEJ adenocarcinoma were included. Hazard ratio (HR) for overall survival (OS) was extracted, and a random-effects model was used for pooled analysis. Median OS, 5-year OS, complete pathologic response (pCR), locoregional and distant failure rates were also calculated.
Results: 22 studies including 18,260 patients were considered for the final analysis. The pooled results demonstrated that combined CTRT do not significantly reduce the risk of death (HR 0.95, 95% CI 0.84-1.07; P = 0.41) but has a positive impact on the risk of relapse (HR 0.85, 95% CI 0.75-0.97; P = 0.01) compared to CT alone. Addition of RT to CT alone significantly increased the odds of pCR by 2.8 (95% CI 2.27-3.47; P < 0.001) and reduced the risk of locoregional failure (OR 0.6, 95% CI 0.39-0.91; P = 0.01) but not the risk of distant metastases (OR 0.81, 95% CI 0.59-1.11; P = 0.19).
Conclusions: In this systematic review and meta-analysis comparing neoadjuvant CTRT with CT for adenocarcinoma of GEJ, we found no difference in terms of median OS, despite a higher pCR rate and a reduced risk of locoregional recurrences for the combined approach. Further studies, preferably large randomized clinical trials, are needed to confirm these results.
Keywords: Chemotherapy; Gastroesophageal junction; Meta-analysis; Neoadjuvant therapy; Radiotherapy.