Title: A commentary on “The prognosis of radiofrequency ablation versus hepatic resection for patients with colorectal liver metastases: A systematic review and meta-analysis based on 22 studies” (Int J Surg 2021;87:105896)
Abstract: Dear Editor, Colorectal cancer is the third most frequently occurring cancer since 2009, and the fifth leading cause of death due to cancer in China [1]. Colorectal liver metastases (CRLM) are present in approximately 25% of patients at initial presentation, and 50% of patients will develop liver metastases during the course of their disease [2]. The treatment strategy for CRLM is usually decided according to tumor size, tumor number, hepatic function and performance status. Many studies on comparing the recurrence and treatment outcomes of CRLM among radiofrequency ablation (RFA) alone, hepatic resection (HR) and HR followed by RFA showed controversial results. RFA was shown to be efficient and safe in patients with unresectable CRLM with a longer survival, but it had doubtful results for resectable metastases. Yang et al. [3] conducted a systematic review and meta-analysis to compare RFA and HR across a comprehensive range of outcomes reported from observational studies. They demonstrated that RFA resulted in a higher recurrence rate and poor long-term survival for CRLM patients. Tumor size, multiple tumors, age, primary node positivity and metachronous metastasis were independent factors of survival. During the past decade, RFA has superseded other ablative therapies due to its low morbidity (8.9%), mortality (0.5%), safety and patient acceptability [4]. A RFA needle is inserted into the tumor either percutaneously or surgically (via laparoscopic or open approach). Alternating current is generated using radio waves and through the RFA needle create local tissue temperatures of 50–100 C° for at least 4–6 minutes, thus causing “coagulation” and tumor necrosis. Usually the duration of RFA is 10–30 minutes because of the slow conduction from the RFA needle electrode through the tumor. To reduce the incidence of local tumor recurrence after RFA, a 1-cm-thick tumor-free margin along all the treated tumors is necessary. This can be achieved by multiple overlapping ablations or modified RFA devices. At present, a new modified RFA device is available in the form of a multi-pled expandable electrode with multiple retractable prongs on the tip and an internally cooled electrode [5]. The results of the study need to be interpreted while considering the potential limitations, including the methodological weakness, short follow-up duration, relatively small number of patients, and the pathology of ablated tumors could not be evaluated preoperatively without a biopsy. Future comparison of HR versus RFA is needed: (1) the first tier of future research is to assess the comparative effectiveness of RFA vs. HR for palliative treatment of CRLMs; (2) the second tier of future research pertains to studying patients with RFA vs HR as first-line treatment in oncological radical treatment of CRLMs; (3) the third tier of future research is to standardize the parameters of RFA to obtain a better curative effect. Provenance and peer review Commentary, internally reviewed. Ethical approval It is not need ethical approval. Sources of funding for your research The comment dose not receive any funding. Author contribution Fei Guo: writing. Xueliang Wu: writing. Lei Han: data collections. Xiaoyu Yang: data analysis. Jun Xue: study design. Research registration unique identifying number (UIN) It is not need registration. Trial registry number None. Guarantor Jun Xue. Declaration of competing interest No conflict of interest. Fei Guo Xueliang Wu Lei Han Xiaoyu Yang Jun Xue Department of General Surgery, The First Affiliated Hospital of Hebei North University, Hebei, 075000, China E-mail addresses:[email protected]