Analysis of therapeutic effect and influencing factors of radiofrequency ablation for colorectal cancer liver metastases / 中华放射学杂志

ABSTRACT

Objective:To explore the efficacy and influencing factors of radiofrequency ablation (RFA) in the treatment of colorectal cancer liver metastases (CRLM).Methods:The clinical and imaging data of 281 patients (477 intrahepatic metastatic tumors) who received percutaneous RFA treatment in Sir Run Run Shaw Hospital, Zhejiang University School of Medicine from December 2009 to December 2020 were retrospectively analyzed. Factors that may affect the efficacy of RFA were recorded, including carcinoembryonic antigen (CEA), differentiation, extrahepatic metastasis, tumor location and size, complications and other information. Patients were followed up through hospital admissions, telephone, etc. The primary endpoints were overall survival (OS) and local tumor progression-free survival (LTPFS). Univariate and multivariate logistic regression models were used to identify predictors of residual tumor. Univariate and multivariate Cox proportional hazards regression were used to identify the influencing factors of LTPFS and OS. The median LTPFS and OS were estimated by the Kaplan-Meier curve and compared by the log-rank test.Results:After RFA, 68 (14.3%) tumor residues were observed. Multivariate logistic regression showed that the risk factors for residual tumor were size ≥20 mm, high-risk and perivascular location, and minimal ablative margin<5 mm. During the follow-up period, the main complication rate was 4.3% (12/281) and the fatality rate was 31.3% (88/281). At the same time, local tumor progression was found in 167 (35.0%) lesions post-RFA. The median time of LTPFS and OS estimated by the Kaplan Meier method were 35.0 (95%CI 26.53-43.48) and 44.0 (95%CI 29.70-58.30) months, respectively. The cumulative proportion of LTPFS and OS were 37.2% and 40.4% respectively in the 5th year. Multivariate Cox proportional hazard regression showed that CEA≥30 ng/ml, tumor size ≥20 mm, and minimal ablative margin<5 mm were risk factors for LTPFS; extrahepatic metastasis, tumor burden>30 mm, and lesion with minimal ablative margin<5 mm were independent risk factors for OS; re-intervention was an independent protective factor for OS.Conclusions:Adequate ablative margin and less tumor burden were beneficial to local tumor control and long-term survival of patients in the RFA treatment; the existence of extrahepatic metastasis was an important risk factor for OS, and re-interventional therapy was beneficial to extend OS.