Retrospective Study
Copyright ©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Oncol. Sep 15, 2020; 12(9): 1044-1055
Published online Sep 15, 2020. doi: 10.4251/wjgo.v12.i9.1044
Oncological outcomes and predictors of radiofrequency ablation of colorectal cancer liver metastases
Chuan-Zhuo Wang, Guang-Xin Yan, He Xin, Zhao-Yu Liu
Chuan-Zhuo Wang, Guang-Xin Yan, He Xin, Zhao-Yu Liu, Department of Radiology, Shengjing Hospital of China Medical University, Shenyang 110004, Liaoning Province, China
Author contributions: Wang CZ and Liu ZY designed the research; Xin H and Yan GX performed the clinical research; Wang CZ, Xin H and Yan GX analyzed the data; Wang CZ and Liu ZY wrote the paper; all authors read and approved the final manuscript.
Supported by National Natural Science Foundation of China, No. 81470086 and No. 81871465.
Institutional review board statement: The study was reviewed and approved by the Medical Ethics Committee of Shengjing Hospital of China Medical University.
Informed consent statement: The patients were not required to give informed consent to the study because the analysis used anonymous clinical data that were obtained after each patient agreed to treatment by written consent.
Conflict-of-interest statement: The authors declare that there are no conflicts of interest related to this article.
Data sharing statement: No additional unpublished data are available.
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: Zhao-Yu Liu, MD, Chairman, Chief Doctor, Department of Radiology, Shengjing Hospital of China Medical University, No. 36 Sanhao Street, Heping District, Shenyang 110004, Liaoning Province, China. liushjh@163.com
Received: May 6, 2020
Peer-review started: May 6, 2020
Revised: June 21, 2020
Accepted: August 15, 2020
Article in press: August 15, 2020
Published online: September 15, 2020
Processing time: 126 Days and 17.9 Hours
ARTICLE HIGHLIGHTS
Research background

Colorectal cancer liver metastasis (CRLM) is a common secondary malignant tumor of the liver and an important cause of tumor-related death. Radiofrequency ablation (RFA) is an accepted alternative therapy for CRLM patients who are unsuitable for resection. However, the relatively high rate of local tumor progression (LTP) is an obstacle to the more widespread use of RFA.

Research motivation

We want to identify the group of CRLM patients who benefit most from RFA, and to provide a reference framework for personalized treatment strategies.

Research objectives

This study aimed to determine the oncological outcomes of RFA in CRLM patients, and to assess predictors that affect LTP-free survival (LTPFS) and overall survival (OS).

Research methods

A retrospective study was conducted. One hundred and thirty-eight lesions in 85 consecutive CRLM patients received RFA treatment from January 2013 to December 2018. Contrast-enhanced computed tomography was performed the first month after RFA to serve as a baseline for subsequent evaluations. The Kaplan-Meier method was used to calculate OS and LTPFS. Univariate and multivariate analyses were performed to determine the predictors of the oncological outcomes.

Research results

There were no RFA procedure-related deaths, and the technique effectiveness rate of the treatment was 89.1% (123/138). The median OS was 36 mo, and the 1-, 3-, and 5-year OS rates were 90.6%, 45.6%, and 22.9%, respectively. Tumor size larger than 3 cm and ablative margin of 5 mm or smaller were the independent predictors of shorter LTPFS, while tumor number greater than 1, size larger than 3 cm, and presence of extrahepatic disease (EHD) were the independent predictors of shorter OS.

Research conclusions

RFA is a safe and effective treatment method for CRLM. Tumor size and ablative margin are the important factors affecting LTPFS, while tumor number, tumor size, and EHD are also critical factors in OS.

Research perspectives

RFA is an effective minimally invasive treatment that can be used as an alternative for patients with unresectable CRLM. Expanding the ablative margin is an effective method to control LTP after RFA. Patients with a single tumor, size of 3 cm or smaller, and no EHD benefit most from RFA.