Radiofrequency Ablation of Hepatocellular Carcinoma

Hyunchul Rhim 한국간담췌외과학회 2012 한국간담췌외과학회 학술대회지 Vol.2012 No.4

Radiofrequency and Microwave Ablation: Expansion of Indication

( Hyunchul Rhim ) 대한간학회 2017 춘·추계 학술대회 (KASL) Vol.2017 No.1

Nonsurgical intervention for colorectal liver metastasis (RFTA)

Hyunchul Rhim 한국간담췌외과학회 2017 한국간담췌외과학회 학술대회지 Vol.2017 No.3

Direction of Tissue Contraction after Microwave Ablation: A Comparative Experimental Study in Ex Vivo Bovine Liver

Lee Junhyok,Rhim Hyunchul,Lee Min Woo,Kang Tae Wook,Song Kyoung Doo,Lee Jeong Kyong 대한영상의학회 2022 Korean Journal of Radiology Vol.23 No.1

Objective: This study aimed to investigate the direction of tissue contraction after microwave ablation in ex vivo bovine liver models. Materials and Methods: Ablation procedures were conducted in a total of 90 sites in ex vivo bovine liver models, including the surface (n = 60) and parenchyma (n = 30), to examine the direction of contraction of the tissue in the peripheral and central regions from the microwave antenna. Three commercially available 2.45-GHz microwave systems (Emprint, Neuwave, and Surblate) were used. For surface ablation, the lengths of two overlapped square markers were measured after 2.5- and 5-minutes ablations (n = 10 ablations for each system for each ablation time). For parenchyma ablation, seven predetermined distances between the markers were measured on the cutting plane after 5- and 10-minutes ablations (n = 5 ablations for each system for each ablation time). The contraction in the radial and longitudinal directions and the sphericity index (SI) of the ablation zones were compared between the three systems using analysis of variance. Results: In the surface ablation experiment, the mean longitudinal contraction ratio and SI from a 5-minutes ablation using the Emprint, Neuwave, and Surblate systems were 28.92% and 1.04, 20.10% and 0.53, and 24.90% and 0.45, respectively (p < 0.001). A positive correlation between longitudinal contraction and SI was noted, and a similar radial contraction was observed. In the parenchyma ablation experiment, the mean longitudinal contraction ratio and SI from a 10-minutes ablation using the three pieces of equipment were 38.60% and 1.06, 32.45% and 0.61, and 28.50% and 0.50, respectively (p < 0.001). There was a significant difference in the longitudinal contraction properties, whereas there was no significant difference in the radial contraction properties. Conclusion: The degree of longitudinal contraction showed significant differences depending on the microwave ablation equipment, which may affect the SI of the ablation zone.

Research Highlight: How to Use Technical and Oncologic Outcomes of Image-Guided Tumor Ablation According to Guidelines by Society of Interventional Oncology and DATECAN?

Lee Min Woo,Rhim Hyunchul 대한영상의학회 2022 Korean Journal of Radiology Vol.23 No.4

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Radiofrequency Ablation for Metastatic Hepatic Tumor in Colorectal Carcinoma

최정혜,Myung-Ju Ahn,Hyunchul Rhim,Heung Woo Lee,Ho-Suk Oh,Young-Yeul Lee,Il-Young Choi,In-Soon Kim 대한암학회 2004 Cancer Research and Treatment Vol.36 No.2

Purpose: The purpose of this study was to assess the efficacy and safety of radiofrequency ablation (RFA) to treat hepatic metastasis in patients with colorectal carcinoma. Materials and Methods: Between May 1999 and July 2002, a total of 45 tumors in 24 patients with colorectal cancer were treated with RFA. Thirteen patients received systemic chemotherapy after the RFA procedure. The ablation was performed percutaneously under ultrasound guidance using cool-tip or expandable electrodes and an RF generator. The medical records as well as the CT scan results taken every 3 months were retrospectively reviewed. Results: The median follow-up duration of the surviving patients was 11.7 months (4.6~32.2 months). Complete tumor necrosis was achieved in 17 patients (70.8%) on an immediate (〈24 hrs) CT scan. The median survival was 17.1 months. The 1- and 2-year survival rates were 80.5 and 25.8%, respectively. In a univariate analysis, complete necrosis, tumor size and post-RFA chemotherapy were significant factors for survival. Nineteen of the 24 patients developed a recurrence or progressed (79.2%). The median progression free survival was 5.5 months. There were no treatment related deaths or serious adverse effects, with the exception of one case of respiratory failure. Conclusion: These results suggest that RFA is a well-tolerated and effective method to treat hepatic metastasis in colorectal carcinomas.(Cancer Res Treat. 2004;36:128-131)

Measurement of Intrahepatic Pressure during Microwave Ablation in an Ex Vivo Bovine Liver Model

( Hae Jin Kim ),( Hyunchul Rhim ),( Min Woo Lee ),( Woo Kyoung Jeong ) 대한소화기학회 2015 Gut and Liver Vol.9 No.6

Background/Aims: We experimented with different ablation methods and two types of microwave antennas to determine whether microwave ablation (MWA) increases intrahepatic pressure and to identify an MWA protocol that avoids increasing intrahepatic pressure. Methods: MWA was performed using either a single-step standard ablation or a stepwise increment ablation paired with either a 16-gauge (G) 2-cm antennaor a 14G 4-cm antenna. We compared the maximum pressures and total ablation volumes. Results: The mean maximum intrahepatic pressures and ablation volumes were as follows: 16G single-step: 37±33.4 mm Hg and 4.63 cm3, 16G multistep: 31±18.7 mm Hg and 3.75 cm3, 14G single-step: 114±45.4 mm Hg and 15.33 cm3, and 14G multistep: 106±43.8 mm Hg and 10.98 cm3. The intrahepatic pressure rose during MWA, but there were no statistically significant differences between the single and multistep methods when the same gauge antennae were used. The total ablation volume was different only in the 14G groups (p<0.05). Conclusions: We demonstrated an increase in intrahepatic pressure during MWA. The multistep method may be used to prevent increased intrahepatic pressure after applying the proper power. (Gut Liver 2015,9:784-790)

간의 국소결정성과형성 : 3중 시기 CT 소견 Triple-phasic CT Features

김영선,서흥석,조온구,고병희,임현철,이승로 한양대학교 의과대학 2000 한양의대 학술지 Vol.20 No.1

Focal nodular hyperplasia is a rare benign tumor of the liver. It shares a lot of features with a fibrolamellar hepatocellular carcinoma in their gross morphology and predisposing ages. But differential diagnosis is invaluable because their treatment modality is absolutely contrary. We experienced a case of focal nodular hyperplasia in a young woman, incidentally found at the ultrasonographic examination for the acute appendicitis, and was difficult to differentiate it from fibrolamellar hepatocellular carcinoma radiologically. Dynamic CT, hepatic arteriographic, and pathologic findings will be discussed, especially in a view of their differential diagnostic point from a fibrolamellar hepatocellular carcinoma.

Laparoscopic Hepatic Resection Versus Laparoscopic Radiofrequency Ablation for Subcapsular Hepatocellular Carcinomas Smaller Than 3 cm: Analysis of Treatment Outcomes Using Propensity Score Matching

Ko Seong Eun,Lee Min Woo,Ahn Soohyun,Rhim Hyunchul,Kang Tae Wook,Song Kyoung Doo,Kim Jong Man,Choi Gyu Seong,Cha Dong Ik,Min Ji Hye,Sinn Dong Hyun,Choi Moon Seok,Lim Hyo Keun 대한영상의학회 2022 Korean Journal of Radiology Vol.23 No.6

Objective: To compare the therapeutic outcomes of laparoscopic hepatic resection (LHR) and laparoscopic radiofrequency ablation (LRFA) for single subcapsular hepatocellular carcinoma (HCC). Materials and Methods: We screened 244 consecutive patients who had received either LHR or LRFA between January 2014 and December 2016. The feasibility of LRFA in patients who underwent LHR was retrospectively assessed by two interventional radiologists. Finally, 60 LRFA-feasible patients who had received LHR and 29 patients who had received LRFA as the first treatment for a solitary subcapsular HCC between 1 cm and 3 cm were finally included. We compared the therapeutic outcomes, including local tumor progression (LTP), recurrence-free survival (RFS), and overall survival (OS) between the two groups before and after propensity score (PS) matching. Multivariable Cox proportional hazard regression was also used to evaluate the difference in OS and RFS between the two groups for all 89 patients. Results: PS matching yielded 23 patients in each group. The cumulative LTP and OS rates were not significantly different between the LHR and LRFA groups after PS matching (p = 0.900 and 0.003, respectively). The 5-year LTP rates were 4.6% and 4.4%, respectively, and OS rates were 100% and 90.7%, respectively. The RFS rate was higher in LHR group without statistical significance (p = 0.070), with 5-year rates of 78.3% and 45.3%, respectively. OS was not significantly different between the LHR (reference) and LRFA groups in multivariable analyses, with a hazard ratio (HR) of 1.33 (95% confidence interval, 0.12–1.54) (p = 0.818). RFS was higher in LHR (reference) than in LRFA without statistical significance in multivariable analysis, with an HR of 2.01 (0.87–4.66) (p = 0.102). Conclusion: There was no significant difference in therapeutic outcomes between LHR and LRFA for single subcapsular HCCs measuring 1–3 cm. The difference in RFS should be further evaluated in a larger study.

Ablative Outcomes of Various Energy Modes for No-Touch and Peripheral Tumor-Puncturing Radiofrequency Ablation: An Ex Vivo Simulation Study

Cha Dong Ik,Lee Min Woo,Song Kyoung Doo,Ko Seong Eun,Rhim Hyunchul 대한영상의학회 2022 Korean Journal of Radiology Vol.23 No.2

Objective: To compare the outcomes of radiofrequency ablation (RFA) using dual switching monopolar (DSM), switching bipolar (SB), and combined DSM + SB modes at two different interelectrode distances (25 and 20 mm) in an ex vivo study, which simulated ablation of a 2.5-cm virtual hepatic tumor. Materials and Methods: A total of 132 ablation zones were created (22 ablation zones for each protocol) using three separable clustered electrodes. The performances of the DSM, SB, and combined DSM + SB ablation modes were compared by evaluating the following parameters of the RFA zones at two interelectrode distances: shape (circularity), size (diameter and volume), peritumoral ablative margins, and percentages of the white zone at the midpoint of the two electrodes (ablative margin at midpoint, AMm) and in the electrode path (ablative margin at electrode path, AMe). Results: At both distances, circularity was the highest in the SB mode, followed by the DSM + SB mode, and was the lowest in the DSM mode. The circularity of the ablation zone showed a significant difference among the three energy groups (p < 0.001 and p = 0.002 for 25-mm and 20-mm, respectively). All size measurements, AMm, and AMe were the greatest in the DSM mode, followed by the DSM + SB mode, and the lowest were with the SB mode (all statistically significant). The white zone proportion in AMm and AMe were the greatest in the SB mode, followed by the DSM + SB mode and DSM in general. Conclusion: DSM and SB appear to be complementary in creating an ideal ablation zone. RFA with the SB mode can efficiently eradicate tumors and create a circular ablation zone, while DSM is required to create a sufficient ablative margin and a large ablation zone.