Ablation Of Liver Tumors Research Articles

Safety and Efficacy of Combined Transarterial Embolization and Percutaneous Radiofrequency Ablation for Liver Tumors Using Cone-Beam CT and Needle Navigation Software in a Single Session

PurposeTo assess the safety and efficacy of single-session transarterial embolization and radiofrequency (RF) ablation for hepatic tumors with the use of needle navigation software. Materials and MethodsRetrospective analysis was conducted of 24 patients with liver cancer undergoing embolization followed by RF ablation between May 2014 and August 2017. Twelve patients each underwent (i) embolization and computed tomography (CT)–guided RF ablation during different sessions (group 1) and (ii) embolization followed by RF ablation with cone-beam CT and Needle Assist software in 1 session (group 2). Median age (70.5 y [range, 58–78 y] vs 70.5 y [range, 50–82 y]; P = .76) and performance status (0/1) were comparable between groups. Median tumor size was significantly larger in group 2 (2 cm [range, 1.0–7.3 cm] vs 3.2 cm [range, 1.1–9.6 cm]; P < .03). Procedure time, effective dose, and number of scans were examined. Efficacy was assessed by modified Response Evaluation Criteria In Solid Tumors after 1 month. Safety was assessed by Society of Interventional Radiology adverse event classification. ResultsGroup 1 had a mean of 8.5 CT scans, vs a mean of 5.0 cone-beam CT scans in group 2 (P < .001). Median procedure times were 110 min in group 1 and 199.5 min in group 2 (P < .001). Median effective doses were 68.8 mSv in group 1 and 55.4 mSv in group 2 (P = .38). There was no difference in complete response between groups (66.7% vs 63.6%; P = 1). ConclusionsTransarterial embolization followed by RF ablation with cone-beam CT and needle guidance software in a single session seems to be safe and effective.

Progress in research of radiofrequency ablation for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors in the world, and its incidence is on the rise. Surgical resection is the standard method for the treatment of primary or metastatic HCC. In the past ten years, the local ablation of liver tumor has become more and more mature, and it has been proved to be an effective method for the treatment of malignant liver diseases. Whether used alone or in combination, it can control the growth of the tumor to a certain extent and prolong the survival time. It also improves the quality of life. This article begins with the mechanism of radiofrequency ablation in the treatment of liver cancer, and introduces in detail the research progress in the treatment of small liver cancer, large liver cancer, huge liver cancer and metastatic liver cancer by radio frequency ablation and the evaluation of the curative effect after operation. Key words: Carcinoma, hepatocellular; Hepatectomy; Catheter ablation

The Role of a Curved Electrode with Controllable Direction in the Radiofrequency Ablation of Liver Tumors Behind Large Vessels.

To investigate the role of a novel curved radiofrequency ablation (RFA) electrode with controllable direction in the ablation of tumors behind large hepatic vessels in ex vivo bovine and in vivo canine liver experiments. Approval from the institutional animal care and use committee was obtained. In ex vivo experiments, conventional multi-tines expandable electrodes, conventional monopolar straight electrodes and novel curved electrodes were used in the ablation of the bovine liver (n = 90). The ablated area, parallel axis, vertical axis and shape of different electrodes were compared. Then, 24 beagle dogs (10months old, female) were used for in vivo experiments. Visual tumor targets deeply located in the portal vein were established, and ultrasound-guided liver ablation was performed with different electrodes. The ablation range, target coverage rate, percentage of normal tissue injury and damage to adjacent vessels were evaluated. The Kruskal-Wallis test and the Chi-squared test were used for statistical analysis. For the ex vivo study with a 3-cm electrode, the ablation area of the multi-tines expandable electrode group (7.14 ± 0.16cm2) was significantly larger than that of the novel curved electrode group (5.01 ± 0.30cm2, P < 0.001) and the monopolar straight electrode group (5.43 ± 0.15cm2, P < 0.001). The results obtained with the 4-cm electrode in the three groups were in accordance with those of the 3-cm electrode. In vivo, the normal tissue damage area of the novel curved electrode group was smaller than that of the multi-tines expandable electrode group (1.10 ± 0.18cm2 vs. 4.00 ± 0.18cm2, P < 0.001). The target coverage rate of the novel curved electrode group was better than that of the monopolar straight electrode group (100% vs. 80.86 ± 1.68%, P < 0.001). The hematoxylin and eosin (H&E) and TUNEL staining results showed that the ablation necrosis area was adjacent to large vessels, but the vascular wall was not significantly damaged in the novel curved electrode group. Our preliminary results showed that the novel curved RFA electrode with controllable direction could achieve accurate ablation for tumors behind large hepatic vessels, with a better target coverage rate and less damage to normal tissue, than conventional multi-tines expandable electrodes and monopolar straight electrodes.

Ischemic complications after percutaneous radiofrequency ablation of liver tumors: Liver volume loss and recovery.

The liver regrows after acute liver injury and liver resection. However, it is not clear whether the liver regenerates in advanced cirrhosis. This study aimed to evaluate the clinical course of, and liver volume change after, ischemic liver complications caused by radiofrequency ablation (RFA) of hepatocellular carcinoma (HCC). We enrolled 35 patients with ischemic complications after RFA. Ischemic complications were defined as rapid elevation of aspartate aminotransferase (AST) to over 500U/L, with typical radiological findings. Patient characteristics and the ischemic liver volume were investigated. Long-term liver volume changes at 3-8months after ischemic complications were also assessed in 32 patients. We also assessed the overall survival rate after ischemic complications. The median value of peak AST was 798U/L (range, 531-4096U/L). The median ischemic liver volume relative to the functional liver volume before RFA was 13% (range, 3.1-46.5%). There was a strong correlation between the peak AST value and the ischemic liver volume (r = 0.84, P < 0.001). The liver volume recovered to some extent in 18 of 32 (56%) patients after ischemic complications. The survival rate after ischemic complications was 45.7% at 5years and correlated with the functional liver volume after ischemic complications (P = 0.02). Ischemic complications after RFA can lead to massive liver parenchymal loss. Although the liver volume recovered to some extent in the majority of our patients, ischemic liver complications after RFA should be avoided to improve the overall survival rate.

Robotic versus Freehand Needle Positioning in CT-guided Ablation of Liver Tumors: A Randomized Controlled Trial.

Purpose To compare the accuracy of freehand versus robotic antenna placement in CT-guided microwave ablation (MWA) of liver tumors. Materials and Methods This study was conducted as a prospective single-center nonblinded randomized controlled trial (Netherlands Trial Registry, NTR6023). Eligible study participants had undergone clinically indicated CT-guided MWA of liver tumors and were able to receive a CT contrast agent. Randomization was performed per tumor after identification on contrast material-enhanced CT images. The primary outcome was the number of antenna repositionings, which was compared by using the Mann-Whitney U test. Secondary outcomes were lateral targeting error stratified by in-plane and out-of-plane targets and targeting time. Results Between February 14 and November 12, 2017, 31 participants with a mean age of 63 years (range, 25-88 years) were included: 17 women (mean age, 57 years; range, 25-77 years) and 14 men (mean age, 70 years; range, 52-88 years). The freehand study arm consisted of 19 participants, while the robotic study arm consisted of 18 participants; six participants with multiple tumors were included in both arms. Forty-seven tumors were assessed; five tumors were excluded from the analysis because of technical limitations. In the robotic arm, no antenna repositioning was required. In the freehand arm, a median of one repositioning was required (range, zero to seven repositionings; P < .001). For out-of-plane targets, lateral targeting error was 10.1 mm ± 4.0 and 5.9 mm ± 2.9 (P = .007) for freehand and robotic procedures, respectively, and for in-plane targets, lateral targeting error was 6.2 mm ± 2.7 and 7.7 mm ± 5.9, respectively (P = .51). Mean targeting time was 19 minutes (range, 8-55 minutes) and 36 minutes (range, 3-70 minutes; P = .001) for freehand and robotic procedures, respectively. Conclusion Robotic antenna guidance reduces the need for antenna repositioning in microwave ablation to accurately target liver tumors and increases accuracy for out-of-plane targets. However, targeting time was greater with robotic guidance than with freehand targeting. © RSNA, 2019.

Outcomes of laparoscopic radiofrequency ablation of liver tumours

Background: Radiofrequency ablation (RFA) of malignant liver tumours is a well-established alternative to resection, particularly in patients with cirrhosis or severe comorbidities. We report on outcomes of laparoscopic RFA (LRFA) as an alternative to access via laparotomy for those tumours that are not amenable to the percutaneous route. Methods: This retrospective study evaluates the introduction of LRFA at a tertiary referral centre between November 2015 and December 2016. All patients were assessed by a multidisciplinary team and if deemed unsuitable for resection were considered for RFA. Those lesions that were inaccessible to percutaneous route such as in superior liver segments close to the diaphragm or at peripheral location underwent LRFA. Results: Six patients underwent LRFA, with one patient requiring conversion to laparotomy due to bleeding. Five patients had HCC and 1 patient had colonic cancer metastasis. All patients had a single lesion, mean size was 27.33 mm. Mean length of stay was 2.67 (range 1-7) days. Two patients suffered minor complications, no death occurred during the follow-up period. There were no local recurrences during the study period (mean follow-up 5.5 months, range 1-11). Conclusion: LRFA is a safe and effective approach to managing tumours deemed not amenable to resection or percutaneous RFA. This technique extends the option of curative treatment to this category of patients. Due to the small number of cases in this study more experience will be needed to confirm these results.

Ablation for Liver Tumors

Ablation for Liver Tumors

Uloga perkutane slikovno vođene ablacije malignih tumora jetre: svjetski trendovi i hrvatska perspektiva

Uloga perkutane slikovno vođene ablacije malignih tumora jetre: svjetski trendovi i hrvatska perspektiva

Initial experience with irreversible electroporation of liver tumours

IntroductionThermal ablation of liver tumours is an established technique used in selected patients with relatively small tumours that can be ablated with margin. Thermal ablation methods are not advisable near larger bile ducts that are sensitive to thermal injury causing strictures and severe morbidity. Irreversible electroporation (IRE) has the possibility to treat these tumours without harming the bile tree. The method is relatively new and has been proven to be feasible and safe with promising oncological results. Methods50 treatments were performed on 42 patients that were not resectable or treatable by thermal ablation (12 women and 30 men) with 59 tumours in total. 51% were colorectal cancer liver metastases (CRCLM) and 34% were hepatocellular carcinomas (HCC). 70% of the treatments were performed using stereotactic CT-guidance for needle placement. Results81% of the treatments were performed with initial success. All patients with missed ablations were re-treated. Local recurrence rate at 3 months was 3% and 37% at one year. The complication rate was low with 2 patients having major complications (Clavien-Dindo grade 3b-5) and without 30-day mortality. ConclusionIRE is safe for treating tumours not suitable for thermal ablation with 63% of patients being without local recurrence after one year in a group of patients with tumours deemed unresectable. IRE has a role in the treatment of unresectable liver tumours close to heat-sensitive structures not suitable for thermal ablation.Level of Evidence: Level 4, Case Series.

Application of dexmedetomidine in radiofrequency ablation of liver tumor

Objective: To evaluate the efficacy and safety of dexmedetomidine as a basic analgesic sedative for patients with radiofrequency ablation of liver tumors. Methods: A total of 443 liver cancer patients underwent percutaneous radiofrequency ablation in the 302 Hospital of PLA from January 2015 to December 2016 were retrospectively studied. The experimental group was dexmedetomidine group, with a total of 165 cases. The control group was pethidine group with a total of 278 cases. The indexes of systolic blood pressure, diastolic blood pressure, heart rate and respiratory rate of two groups were collected before and after operation, and the VAS score and incidence of nausea and adverse reactions were recorded. Results: The results of the experimental group added dose of pethidine (64.6 mg) lower than that of the control group pethidine dose (90.8 mg), the difference was statistically significant (Z=-10.205 3, P<0.01). The experimental group and the control group with VAS score average value was not statistically significant(Z=1.801 9, P=0.076), group two with 4 points for the critical point of the stratification, more than 4 points and<4 group comparison, the test group VAS score greater than 4 were significantly lower than the control group (χ(2)=7.05, P=0.007 9). The systolic blood pressure and diastolic blood pressure in the experimental group were significantly lower than those before operation (P<0.01), while the systolic blood pressure and diastolic blood pressure in the control group significantly increased compared with those before operation. Dexmedetomidine has the effect of stabilizing hemodynamics. The heart rate of the two groups decreased, and the rate of heart rate decreased in the experimental group. In addition, dexmedetomidine did not significantly increase the incidence of nausea and vomiting compared with the control group. Conclusions: Dexmedetomidine is safe and effective as a basic drug for analgesic and sedative in patients with liver tumor radiofrequency ablation.

Outcomes of laparoscopic radiofrequency ablation of liver tumours

Outcomes of laparoscopic radiofrequency ablation of liver tumours

Liver tumor ablation assisted by image fusion

Liver tumor ablation assisted by image fusion

Modern methods of ablation of malignant tumors of the liver

The purpose of this review is to demonstrate the possibility of performing various methods of thermal and non-thermal ablation in patients with primary and metastatic liver tumors on the basis of data available in the world medical literature.As conservative variants of local action in patients with non-resectable primary and secondary liver tumors and inoperable patients, various ablative techniques have been developed and used to achieve local control over the disease and increase the life expectancy of this group of patients. These include: radiofrequency ablation, microwave ablation, HIFU therapy, laser ablation, cryotherapy, chemical destruction of the tumor, irreversible electroporation, stereotactic radiation therapy.The effectiveness of these ablation methods depends on the size and localization of the tumor focus, and for thermal techniques — also on its location relative to large vessels. Ablative techniques have the maximum efficiency (in some cases, similar to surgical intervention) when exposed to early forms of primary cancer or secondary tumor formation of the liver in the presence of a solitary node with a maximum size up to 5 cm or 3 and less foci size up to 3 cm. The effectiveness of local destruction of tumor formations of the liver of larger diameter is increased by carrying out ablation by the second stage after performing chemoembolization of the hepatic artery or by combining various techniques of local action.The use of various modern methods of ablation of solid primary and secondary liver tumors in medical practice can expand the possibilities of antitumor treatment of this category of patients.

Ultrasound single-phase CBE imaging for monitoring radiofrequency ablation

Radiofrequency (RF) ablation (RFA) is the most commonly used minimally invasive procedure for thermal ablation of liver tumors. Ultrasound not only provides real-time feedback of the electrode location for RFA guidance but also enables visualization of the tissue temperature. Changes in backscattered energy (CBE) have been widely applied to ultrasound temperature imaging for assessing thermal ablation. Pilot studies have revealed that significant shadowing features appear in CBE imaging and are caused by the electrode and RFA-induced gas bubbles. To resolve this problem, the current study proposed ultrasound single-phase CBE imaging based on positive CBE values. An in vitro model with tissue samples derived from the porcine tenderloin was used to validate the proposed method. During RFA with various electrode lengths, ultrasound scans of tissue samples were obtained using a clinical ultrasound scanner equipped with a convex array transducer of 3 MHz. Raw image data comprising 256 scan lines of backscattered RF signals were acquired for B-mode, conventional CBE, and single-phase CBE imaging by using the proposed algorithmic scheme. The ablation sizes estimated using CBE imaging and gross examinations were compared to calculate the correlation coefficient. The experimental results indicated that single-phase CBE imaging largely suppressed artificial CBE information in the shadowed region. Moreover, compared with conventional CBE imaging, single-phase CBE imaging provided a more accurate estimation of ablation sizes (the correlation coefficient was higher than 0.8).

Acute pericarditis following treatment of a metastatic liver tumor with radiofrequency ablation: a case report

BackgroundRadiofrequency ablation is a common and minimally invasive procedure used to treat liver tumors. However, the potential threat of heat injury to adjacent structures if the hepatic lesion is near the diaphragm is often overlooked and misunderstood. Rare cardiovascular complications have been reported. How best to identify the patients at risk to allow for prompt treatment is an important issue.Case presentationA 56-year-old man with underlying oral cancer received radiofrequency ablation for a metastatic liver tumor at segment II. Pleuritic chest pain developed on the day after radiofrequency catheter ablation. Diffuse ST elevation and echocardiography showed the new onset of small to moderate pericardial effusion without tamponade sign. Inflammatory markers were also elevated. Acute pericarditis due to heat penetration and stimulation was favored. His symptoms and signs resolved after treatment with anti-inflammatory medication.ConclusionPotential cardiovascular complications are possible after radiofrequency catheter ablation for liver tumors located at segment II. Artificial ascites with normal saline before radiofrequency ablation may separate the liver and diaphragm to prevent cardiac complications. During the procedure, electrocardiographic monitoring and close observation of the patient’s symptom are required. Echocardiography can be used to confirm cardiac complications.

Perforation of the esophagus due to thermal injury after laparoscopic radiofrequency ablation for hepatocellular carcinoma: a case for caution

BackgroundSeveral reported complications associated with radiofrequency ablation for liver tumors are due to thermal damage of neighboring organs. We herein report a first case of esophageal perforation due to thermal injury of laparoscopic radiofrequency ablation (RFA).Case presentationA 75-year-old woman was treated repeatedly with RFA (percutaneous and laparoscopic) and transcatheter arterial chemoembolization for hepatocellular carcinoma. One week after laparoscopic RFA for recurrent HCC located in segment 2 of the liver, dysphagia and thoracic pain occurred. Upper gastrointestinal endoscopy revealed a perforated esophageal ulcer at the esophago-gastric junction. Inflammation was localized because of severe intra-abdominal adhesion due to repeat surgery, so we decided to treat the patient conservatively. The perforation of the esophagus gradually scarred, and exacerbation did not occur after restarting oral intake.ConclusionsWhen patients with a history of abdominal surgery or intra-abdominal inflammation undergo thermal ablation therapy, caution is required, as there is a possibility of thermal injury of unexpected organs.

Comparison of CT/MRI-CEUS and US-CEUS fusion imaging techniques in the assessment of the thermal ablation of liver tumors

Purpose: To compare the applicability of fusion imaging between contrast-enhanced ultrasound (CEUS) and computed tomography (CT) or magnetic resonance imaging (MRI) (CT/MRI-CEUS fusion imaging) and fusion imaging between CEUS and ultrasound (US-CEUS fusion imaging) in the assessment of treatment response during liver cancer ablation.Methods: From August to December 2015, patients who underwent US-guided thermal ablation of liver tumors at our hospital with available CT/MRI images were enrolled consecutively. Both CT/MRI-CEUS and US-CEUS fusion imaging were performed in all patients to evaluate treatment responses. The applicable rate, success rate of registration and duration time were recorded. Complications were monitored in the follow-up period, and CECT/MRI within three months were taken as the standard reference of technical efficacy.Results: A total of 157 liver tumors (19 ± 8 mm, range 8–55 mm) in 115 patients (54 ± 11 years old, range 2 7∼ 84 years old) were enrolled. The applicable rate of US-CEUS fusion imaging was 61.1% (96/157) because of inconspicuous lesions in US, lower than that of CT/MRI-CEUS fusion imaging (99.7% (155/157)) (p < .05). However, the success rate of registration in US-CEUS fusion imaging (93.8% (90/96)) was superior to that of CT/MRI-US fusion imaging (81.3% (126/155)) (p < .05), especially for cases combined with alternative preablation surgeries or procedures (p < .05). The technical efficacy rate was 99.3% (150/151) according to the CECT/CEMRI.Conclusions: Both CT/MRI-CEUS and US-CEUS fusion imaging are feasible means for intraprocedural immediate evaluation of treatment response for liver thermal ablation. US-CEUS fusion imaging is preferred because of its convenience and higher success rate of registration.

Study on the methods and effect of creating artificial ascites in thermal ablation of liver or kidney tumors under ultrasonic guidance

Objective To evaluate the effect of artificial ascites under ultrasonic guidance in the thermal ablation of liver or kidney tumors, so as to provide basis for successfully creating artificial ascites, increasing the complete ablation rate of the tumors and reducing the damage of important organs. Methods Seven hundred and thirty-six patients with artificial ascites were performed under ultrasonic guidance during the thermal ablation of liver or kidney tumors and six hundred and seventy-nine patients were successfully performed. The success rate of creating artificial ascites at different sites, time requirement, the effect of ascites, puncture times were analyzed, while curative effect and complications were evaluated and summarized. Results The success rate of creating artificial ascites was 92.3%; the average time of creating artificial ascites was(9.1±1.3)minutes; the average puncture times was(1.1±0.2)times; complete ablation was 98.7%; the complication of ascites creation was 0.44%, minor complications after ablation was 6.20%, severe complications was 0.59%. The required fluid volume and success rates for the creation of artificial ascites in different sites were different. The volume of fluid needed was relatively high in the liver-gastric space, and the success rate was relatively low; the success rate of liver septum and liver-kidney crypts was the highest. Heat injury complications of the important organs such as gastrointestinal tract, esophagus, diaphragm near the liver or kidney tumors were 0. Conclusions The establishment of artificial ascites improves the local curative effect and reduces the complication of tumors ablation in difficult locations. The methods and effect of artificial ascites in different parts of liver or kidney are different. Key words: Ultrasonic guidance; Liver tumors; Kidney tumors; Thermal ablation; Artificial ascites

Oliguric acute kidney injury after microwave ablation of large liver tumors: incidence and preventive measures

Purpose: Acute kidney injury (AKI), especially oliguric AKI, is a recognized complication following microwave ablation (MWA) of large liver tumors. This study evaluated the clinical features, mechanisms, risk factors and prevention strategies for oliguric AKI after MWA of large liver tumors.Methods: From March 2011 to May 2015, 441 patients with liver tumors ≧5 cm received MWA in our hospital. The clinical features, prevention strategies, further mechanisms and possible risk factors for oliguric AKI after MWA were analyzed.Results: One hundred four (23.6%) patients had AKI after MWA; 11 (10.6%) patients had oliguric AKI, and 93 (89.4%) patients had nonoliguric AKI. All patients with nonoliguric AKI recovered without any special treatments. The eleven patients with oliguric AKI received appropriate treatments and had completely normal renal function three months later. Using double needles for ablation was a risk factor for nonoliguric AKI, while high preoperative levels of red blood cells (RBC), hemoglobin (HGB) and albumin (Alb) were risk factors for oliguric AKI. The decrease levels of hemoglobin were significantly high in oliguric AKI patients (p < .05). Patients with oliguric AKI had abnormally high postoperative transaminase and renal function indicators. Compared to postoperative prevention, intraoperative prevention significantly lowered the occurrence of oliguric AKI (0% vs. 3.7%, p = .018) and shortened the hospital stay.Conclusions: Patients who underwent MWA for large liver tumors are prone to develop oliguric AKI. Implementation of intraoperative strategies during MWA can effectively prevent the occurrence of this severe complication.

Surgical microwave ablation of primary and secondary liver tumours: iconographic follow-up and local control

Surgical microwave ablation of primary and secondary liver tumours: iconographic follow-up and local control