Normal Saline Addition to RFA Increases Energy and Heat Output Leading to Complete HCC Ablation and Higher Cure Rate

Abstract

Introduction: One of the potential approaches to increase the effectiveness of radiofrequency ablation (RFA) is to modify the biologic environment of treated tissues. So, several researchers have studied increasing RFA heating by the combined intra-tumoral injection of diverse concentrations and volumes of saline.Aim: Study the effect of normal saline (NS) on cool-tip radiofrequency machine parameters, success rate and frequency of complications when used for ablation of HCV-related hepatocellular carcinoma (HCC). Patients and methods:This study included 80 patients with HCC (proven by histopathology and/or typical feature on triphasic CT abdomen and significantly elevated alpha-fetoprotein). They were randomly allocated to either cool-tip RFA preceded by intra-tumor normal saline injection, group 1 (RFA+S) that included 40 patients, or treated with cool-tip RFA only, group 2 (RFA) that included 40 patients Results:The RF machine parameters in our study showed that the impedance; (minimum, P=0.024, maximum, P=0.027 and mean, P=0.017) and the tip temperature (minimum, P=0.19 maximum, P=0.069 and mean, P=0.086) were significantly lower in RFA+S group than RFA group. The current (heat deposition) was significantly higher in RFA+S group than RFA group (P=0.018). The procedure was successful in all the RFA+S group 40 (100%) compared to 22 (55%) of the RFA alone group (P <0.01). Those who failed RFA alone, 18 (45%) were shifted to percutaneous ethanol injection (PEI). The procedure related complications were comparable in both groups with no reported major side effect or death. Conclusion:Normal saline decreases impedance and increases energy deposition in RFA leading to marked increase in ablation volume and success rate, so, RFA preceded by intra-tumor normal saline injection is more effective than RFA alone. It should be widely used in ablation of HCC as it is safe, highly effective, one session procedure, non-costly and easy to perform.