Meta-Analysis
Copyright ©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Aug 6, 2021; 9(22): 6357-6379
Published online Aug 6, 2021. doi: 10.12998/wjcc.v9.i22.6357
Neoadjuvant chemotherapy for patients with resectable colorectal cancer liver metastases: A systematic review and meta-analysis
Yue Zhang, Long Ge, Jun Weng, Wen-Yu Tuo, Bin Liu, Shi-Xun Ma, Ke-Hu Yang, Hui Cai
Yue Zhang, Jun Weng, Wen-Yu Tuo, Bin Liu, Shi-Xun Ma, Hui Cai, General Surgery Clinical Medical Center, Gansu Provincial Hospital, Lanzhou 730000, Gansu Province, China
Long Ge, Ke-Hu Yang, Evidence Based Social Science Research Center, School of Public Health, Lanzhou University, Lanzhou 730000, Gansu Province, China
Author contributions: Zhang Y, Ge L, Yang KH, and Cai H designed research; Zhang Y, Weng J, Tuo WY, Ma SX, and Liu B conducted the literature search; Zhang Y and Ge L collected and retrieved the data; Zhang Y, Weng J, and Tuo WY analyzed the data; Zhang Y wrote and revised the manuscript; All authors approved the final version.
Supported by the Natural Science Foundation of Gansu Province, China, No. 18JR3RA052; the Gansu Province Da Vinci Robot High End Diagnosis and Treatment Personnel Training Project; the National Key Research and Development Program Task Book, No. 2018YFC1311506; and the Lanzhou Talent Innovation and Entrepreneurship Project Task Contract, No. 2016-RC-56.
Conflict-of-interest statement: No conflict of interest.
Data sharing statement: No additional data are available.
PRISMA 2009 Checklist statement: The authors have read the PRISMA 2009 Checklist, and the manuscript was prepared and revised according to the PRISMA 2009 Checklist.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Hui Cai, MD, PhD, Chief Doctor, Director, Professor, Surgical Oncologist, General Surgery Clinical Medical Center, Gansu Provincial Hospital, No. 204 Donggang West Road, Lanzhou 730000, Gansu Province, China. Caialonteam@163.com
Received: February 16, 2021
Peer-review started: February 16, 2021
First decision: April 6, 2021
Revised: April 14, 2021
Accepted: June 16, 2021
Article in press: June 16, 2021
Published online: August 6, 2021
Abstract
BACKGROUND

In recent years, neoadjuvant chemotherapy (NAC) has been increasingly used in patients with resectable colorectal liver metastases. However, the efficacy and safety of NAC in the treatment of resectable colorectal liver metastases (CRLM) are still controversial.

AIM

To assess the efficacy and application value of NAC in patients with resectable CRLM.

METHODS

We searched PubMed, Embase, Web of Science, and the Cochrane Library from inception to December 2020 to collect clinical studies comparing NAC with non-NAC. Data processing and statistical analyses were performed using Stata V.15.0 and Review Manager 5.0 software.

RESULTS

In total, 32 studies involving 11236 patients were included in this analysis. We divided the patients into two groups, the NAC group (that received neoadjuvant chemotherapy) and the non-NAC group (that received no neoadjuvant chemotherapy). The meta-analysis outcome showed a statistically significant difference in the 5-year overall survival and 5-year disease-free survival between the two groups. The hazard ratio (HR) and 95% confidence interval (CI) were HR = 0.49, 95%CI: 0.39-0.61, P = 0.000 and HR = 0.48 95%CI: 0.36-0.63, P = 0.000. The duration of surgery in the NAC group was longer than that of the non-NAC group [standardized mean difference (SMD) = 0.41, 95%CI: 0.01-0.82, P = 0.044)]. The meta-analysis showed that the number of liver metastases in the NAC group was significantly higher than that in the non-NAC group (SMD = 0.73, 95%CI: 0.02-1.43, P = 0.043). The lymph node metastasis in the NAC group was significantly higher than that in the non-NAC group (SMD = 1.24, 95%CI: 1.07-1.43, P = 0.004).

CONCLUSION

We found that NAC could improve the long-term prognosis of patients with resectable CRLM. At the same time, the NAC group did not increase the risk of any adverse event compared to the non-NAC group.

Keywords: Colorectal neoplasm, Neoadjuvant chemotherapy, Systematic review, Randomized controlled trials, Meta-analysis, Colorectal liver metastases

Core Tip: Although hepatectomy is currently recommended as the most reliable treatment for colorectal liver metastasis, there are still a great number of patients who have recurrences and metastases after surgical resection. In recent years, neoadjuvant chemotherapy (NAC) has been increasingly used in patients with resectable colorectal liver metastases (CRLM). However, the efficacy and safety of NAC in the treatment of CRLM are still controversial. Therefore, we conducted a systematic review and meta-analysis to assess the value of NAC in patients with CRLM.