Published online Mar 21, 2024. doi: 10.3748/wjg.v30.i11.1621
Peer-review started: December 23, 2023
First decision: January 4, 2024
Revised: January 18, 2024
Accepted: March 4, 2024
Article in press: March 4, 2024
Published online: March 21, 2024
Processing time: 88 Days and 15.2 Hours
The incidence of adenocarcinoma (AC) in the esophagus is increasing, especially in the Western countries, in contrast to the incidence of squamous cell carcinomas (SCC). Neoadjuvant therapy before surgery can improve patient survival in advanced stages. The superiority of neoadjuvant modalities, especially for ACs, remains unclear. Previous meta-analyses have numerous limitations, including the pooled populations of AC and SCC, which makes the application of their results specifically to either subtype difficult.
The superiority of neoadjuvant therapy has been proven previously; however, determining which modality has a greater benefit, especially for esophageal AC, remains uncertain. In this study, we performed a comprehensive, up-to-date investigation to compare the efficacy of neoadjuvant chemotherapy (nCT) and neoadjuvant chemoradiotherapy (nCRT) in the surgical treatment of AC of the esophagus and esophageal junction.
To address the questions of this meta-analysis, we used the PICO protocol to evaluate data from patients with esophageal or cardiac AC, who underwent neoadjuvant therapy before surgery. Intervention was preoperative nCT, which was compared with nCRT. We investigated the following outcomes: Survival, remission rate, mortality, short- and long-term clinical and surgical complications, and quality of life.
Following the PICO protocol, two authors independently performed a comprehensive search of multiple databases using the predefined criteria. Statistical analyses were performed by biostatisticians to calculate odds ratio and hazard ratio with the 95%CI. Results were visualized using forest plots and Kaplan-Meier curves. The Risk of Bias Tool 2 and GRADE approach were used to assess the quality of the results.
Ten articles were included after selection. After statistical analysis, we observed that 30-d mortality (P = 0.015) and pathological complete response (P < 0.001) were higher in the nCRT group than in the nCT group; however, no significant difference was observed for long-term survival. The risk of renal failure (P = 0.039) was higher in the nCT group, and the incidence of nausea or vomiting was 9% in the nCT group compared to 3% in the nCRT group. No significant difference was reported in other clinical or surgical complications.
Although the superiority of neoadjuvant therapy has been previously demonstrated, nCRT may increase pathological complete response and 30-d mortality, without improving long-term survival. Furthermore, nCT may lead to some adverse effects, which can decrease the quality of life.
The present study predominantly analyzed retrospective data, potentially introducing research bias; therefore, future randomized studies with more detailed data collection are warranted.