Effects of neoadjuvant chemotherapy chemoradiotherapy in the treatment of esophageal adenocarcinoma: A systematic review and meta-analysis.

Background: Neoadjuvant therapy is an essential modality for reducing the clinical stage of esophageal cancer; however, the superiority of neoadjuvant chemotherapy (nCT) or neoadjuvant chemoradiotherapy (nCRT) is unclear. Therefore, a discussion of these two modalities is necessary.

Aim: To investigate the benefits and complications of neoadjuvant modalities.

Methods: To address this concern, predefined criteria were established using the PICO protocol. Two independent authors performed comprehensive searches using predetermined keywords. Statistical analyses were performed to identify significant differences between groups. Potential publication bias was visualized using funnel plots. The quality of the data was evaluated using the Risk of Bias Tool 2 (RoB2) and the GRADE approach.

Results: Ten articles, including 1928 patients, were included for the analysis. Significant difference was detected in pathological complete response (pCR) [ < 0.001; odds ratio (OR): 0.27; 95%CI: 0.16-0.46], 30-d mortality ( = 0.015; OR: 0.4; 95%CI: 0.22-0.71) favoring the nCRT, and renal failure ( = 0.039; OR: 1.04; 95%CI: 0.66-1.64) favoring the nCT. No significant differences were observed in terms of survival, local or distal recurrence, or other clinical or surgical complications. The result of RoB2 was moderate, and that of the GRADE approach was low or very low in almost all cases.

Conclusion: Although nCRT may have a higher pCR rate, it does not translate to greater long-term survival. Moreover, nCRT is associated with higher 30-d mortality, although the specific cause for postoperative complications could not be identified. In the case of nCT, toxic side effects are suspected, which can reduce the quality of life. Given the quality of available studies, further randomized trials are required.