Major complications after radio-frequency thermal ablation of hepatic tumors: spectrum of imaging findings

An exploration of radiological signs in post-intervention liver complications

The advent and progression of radiological techniques in the past few decades have revolutionized the diagnostic and therapeutic landscape for liver diseases. These minimally invasive interventions, ranging from biopsies to complex therapeutic procedures like transjugular intrahepatic portosystemic shunt placement and transarterial embolization, offer substantial benefits for the treatment of patients with liver diseases. They provide accurate tissue diagnosis, allow real-time visualization, and render targeted treatment for hepatic lesions with enhanced precision. Despite their advantages, these procedures are not without risks, with the potential for complications that can significantly impact patient outcomes. It is imperative for radiologists to recognize the signs of these complications promptly to mitigate further health deterioration. Ultrasound, CT, and MRI are widely utilized examinations for monitoring the complications. This article presents an overarching review of the most commonly encountered hepatobiliary complications post-radiological interventions, emphasizing their imaging characteristics to improve patient post-procedure management.

Local Ablation for Hepatocellular Carcinoma: 2024 Expert Consensus-Based Practical Recommendations of the Korean Liver Cancer Association

Local ablation for hepatocellular carcinoma, a non-surgical option that directly targets and destroys tumor cells, has advanced significantly since the 1990s. Therapies with different energy sources, such as radiofrequency ablation, microwave ablation, and cryoablation, employ different mechanisms to induce tumor necrosis. The precision, safety, and effectiveness of these therapies have increased with advances in guiding technologies and device improvements. Consequently, local ablation has become the first-line treatment for early-stage hepatocellular carcinoma. The lack of organized evidence and expert opinions regarding patient selection, preprocedure preparation, procedural methods, swift post-treatment evaluation, and follow-up has resulted in clinicians following varied practices. Therefore, an expert consensus-based practical recommendation for local ablation was developed by a group of experts in radiology and hepatology from the Research Committee of the Korean Liver Cancer Association in collaboration with the Korean Society of Image-Guided Tumor Ablation to provide useful information and guidance for performing local ablation and for the pre- and post-treatment management of patients.

Local Ablation for Hepatocellular Carcinoma: 2024 Expert Consensus-Based Practical Recommendations of the Korean Liver Cancer Association

Local ablation for hepatocellular carcinoma (HCC), a non-surgical option that directly targets and destroys tumor cells, has advanced significantly since the 1990s. Therapies with different energy sources, such as radiofrequency ablation, microwave ablation, and cryoablation, employ different mechanisms to induce tumor necrosis. The precision, safety, and effectiveness of these therapies have increased with advances in guiding technologies and device improvements. Consequently, local ablation has become the first-line treatment for early-stage HCC. The lack of organized evidence and expert opinions regarding patient selection, pre-procedure preparation, procedural methods, swift post-treatment evaluation, and follow-up has resulted in clinicians following varied practices. Therefore, an expert consensus-based practical recommendation for local ablation was developed by a group of experts in radiology and hepatology from the Research Committee of the Korean Liver Cancer Association in collaboration with the Korean Society of Image-guided Tumor Ablation to provide useful information and guidance for performing local ablation and for the pre- and post-treatment management of patients.

Local ablation for hepatocellular carcinoma: 2024 expert consensus-based practical recommendation of the Korean Liver Cancer Association

Local ablation for hepatocellular carcinoma (HCC), a non-surgical option that directly targets and destroys tumor cells, has advanced significantly since the 1990s. Therapies with different energy sources, such as radiofrequency ablation, microwave ablation, and cryoablation, employ different mechanisms to induce tumor necrosis. The precision, safety, and effectiveness of these therapies have increased with advances in guiding technologies and device improvements. Consequently, local ablation has become the firstline treatment for early-stage HCC. The lack of organized evidence and expert opinions regarding patient selection, pre-procedure preparation, procedural methods, swift post-treatment evaluation, and follow-up has resulted in clinicians following varied practices. Therefore, an expert consensus-based practical recommendation for local ablation was developed by a group of experts in radiology and hepatology from the Research Committee of the Korean Liver Cancer Association in collaboration with the Korean Society of Image-guided Tumor Ablation to provide useful information and guidance for performing local ablation and for the pre- and posttreatment management of patients.

Complications of Percutaneous Radiofrequency Ablation for Hepatocellular Carcinoma

Radiofrequency ablation (RFA) is a potentially curative treatment option for early Hepatocellular carcinoma. The RFA is considered safe with a relatively low incidence of complications ranging from 2%-7.9%. Though most of the complications are self-limiting, sometimes they can be life-threatening. The occurrence of the particular complication depends on various factors like tumour location and morphology, underlying disease and ablation technique. A detailed understanding of potential complications along with the associated risk factors will help to employ strategies to prevent them, identify them early and manage them when they occur. This article demonstrates various radiofrequency ablation-related complications and discusses the risk factors and technical strategies to minimise them and achieve complete ablation of the tumour.

Rhodotorula mucilaginosa Fungemia in an Infected Biloma Patient Following a Traumatic Liver Injury

Rhodotorula mucilaginosa fungemia is rare and highly resistant to antifungal therapy. We herein report a case involving a 31-year-old male admitted after a high-velocity road traffic accident. He sustained a grade IV liver injury with right hepatic vein thrombosis, which necessitated an urgent laparotomy. Post-operatively, repeated imaging of the abdomen revealed the presence of a biloma. Percutaneous subdiaphragmatic drainage was carried out but appeared ineffective, prompting a second surgery for an urgent hemi-hepatectomy. The patient was then nursed in the intensive care unit (ICU); however, during his stay in the ICU, he became more sepsis, which was evident by worsening ventilatory support and a rise in septic parameters from the biochemistry parameters. Despite intravenous piperacillin-tazobactam and fluconazole, his septic parameters did not improve and a full septic workup was conducted and was found to be positive for Rhodotorula mucilaginosa from the blood cultures. After discussion with the infectious disease physicians and clinical microbiologists, it was decided to initiate a course of intravenous meropenem and amphotericin B based on minimum inhibitory concentration (MIC) values, considering the patient's extended ICU stay and catheter use. Eventually, after successfully weaning off mechanical ventilation, the patient was discharged from ICU care. This case underscores the necessity of individualized approaches, combining timely imaging, appropriate drainage techniques, and tailored treatments to optimize outcomes for such intricate post-traumatic complications.

Diaphragmatic Liver Herniation after Radiofrequency Ablation of a Secondary Liver Tumor

Radiofrequency thermal ablation (RFA) is widely used and has been accepted for the treatment of unresectable tumors. The leading technique that is used is percutaneous RFA under CT or US guidance. Multicenter surveys report acceptable morbidity and mortality rates for RFA. The mortality rate ranges from 0.1% to 0.5%, the major complication rate ranges from 2% to 3%. Diaphragmatic injury is a rare complication and it is described after RFA of subdiaphragmatic tumors. Most of them are without clinical importance. There are some case reports about diaphragmatic herniation of the intestine into the pleural cavity. We present a case of diaphragmatic perforation resulting in the herniation of the liver into the pleural cavity. A thoracotomy was performed, the liver was lowered back into the peritoneal cavity and the perforation was closed with mesh.

Loco-regional therapies competing with radiofrequency ablation in potential indications for hepatocellular carcinoma: a network meta-analysis

BACKGROUND/AIMS

There is no clear consensus on the relative ranking of interventional and radiation techniques with indications similar to those of radiofrequency ablation (RFA) for the treatment of early hepatocellular carcinoma (HCC). We used a network meta-analysis to compare the efficacy of non-surgical treatments for early HCC.

METHODS

We searched databases for randomized trials assessing the efficacy of loco-regional treatments for HCCs ≤5 cm with no extrahepatic spread or portal invasion. The primary outcome was the pooled hazard ratio (HR) for overall survival (OS), and secondary outcomes included overall and local progression-free survival (PFS). A frequentist network meta-analysis was performed, and the relative ranking of therapies was assessed with P-scores.

RESULTS

Nineteen studies comparing 11 different strategies in 2,793 patients were included. Chemoembolization plus RFA improved OS better than RFA alone (HR 0.52, 95% confidence interval [CI] 0.33-0.82; P-score=0.951). Cryoablation, microwave ablation, laser ablation, and proton beam therapy had similar effects on OS compared with RFA. For overall PFS, but not local PFS, only chemoembolization plus RFA performed significantly better than RFA (HR 0.61, 95% CI 0.42-0.88; P-score=0.964). Injection of percutaneous ethanol or acetic acid was significantly less effective than RFA for all measured outcomes, while no differences in progression outcomes were identified for other therapies included in the network.

CONCLUSION

Our results suggest that chemoembolization combined with RFA is the best option for local treatment of early HCC. Cases with potential contraindications for RFA may benefit from a tailored approach using thermal or radiation modalities.

Factors associated with increased risk of peritoneal seeding after radiofrequency ablation for hepatocellular carcinoma

PURPOSE

To evaluate the incidence, risk factors, and prognosis associated with peritoneal seeding after percutaneous radiofrequency ablation (RFA) for HCC, focusing on viable tumors after previous locoregional treatment, including TACE and RFA.

METHODS

Exactly 290 patients (mean age, 67.9 years ± 9.74; 223 men) with 383 HCCs (mean size, 15.9 mm ± 5.49) who underwent RFA between June 2012 and December 2019 were included in this retrospective study. Among them, 158 had history of previous treatment (mean number, 1.3 ± 1.8) with 109 viable HCCs. Cumulative seeding after RFA was estimated using the Kaplan-Meier method. Independent factors affecting seeding were investigated using multivariable Cox proportional hazards regression analysis.

RESULTS

Median follow-up was 1175 days (range: 28-4116). Seeding incidence was 4.1 (12/290) and 4.7% (17/383) per patient and tumor, respectively. The median time interval between RFA and detection of seeding was 785 days (range: 81-1961). Independent risk factors for seeding included subcapsular tumor location (hazard ratio [HR] 4.2; 95% confidence interval [CI] 1.4, 13.0; p = 0.012) and RFA for viable HCC after previous locoregional treatment (HR 4.5; 95% CI 1.7, 12.3; p = 0.003). Subgroup analysis for viable tumors, revealed no significant difference in cumulative seeding rates between the TACE and RFA groups (p = 0.078). Cumulative overall survival rates differed significantly between patients with and without seeding metastases (p < 0.001).

CONCLUSION

Peritoneal seeding after RFA is a rare, delayed complication. Subcapsular-located and viable HCC after previous locoregional treatment are potential risk factors for seeding. Seeding metastases could affect the prognosis of patients who cannot receive local therapy.

Feasibility of laparoscopic microwave ablation of caudate tumors: a case series

Microwave ablation of liver tumors allows preservation of liver parenchyma with good oncologic outcomes. However, ablation of tumors in the caudate lobe is particularly challenging. Adjacent critical anatomy, particularly the biliary hilum, has led to caudate location being considered a relative contraindication to ablation. To date, no series have described laparoscopic microwave ablation of caudate tumors of the liver. We describe our early experience with laparoscopic microwave ablation of caudate tumors. In this retrospective review of a prospectively maintained single-institution database, six patients with six primary or secondary caudate tumors underwent laparoscopic microwave ablation with no complications. At a median follow-up of 10.5 months, five out of six patients are free of caudate recurrence. Laparoscopic microwave ablation of caudate tumors is feasible. Long-term follow-up is needed to determine if local recurrence risk is higher than in other anatomical segments.

Denatured collagen inhibits neuroblastoma tumor-sphere migration and growth via the LOX/LOXL2 - FAK signaling pathway

A complex interplay exists within the tumor microenvironment and extracellular matrix, which could contribute to solid tumor progression. Collagen, a major component of the extracellular matrix, may correlate with cancer prognosis. While thermal ablation has shown promise as a minimally invasive treatment of solid tumors, its impact on collagen is still unknown. In this study, we demonstrate that thermal ablation, but not cryo-ablation, induces irreversible collagen denaturation in a neuroblastoma sphere model. Prolonged collagen denaturation resulted in a significant reduction in sphere stiffness, migration, and proliferation, and an increase in apoptosis. Mechanistic analysis revealed that collagen denaturation inhibited collagen cross-linking, reduced extracellular LOX/LOXL2 expression, and resulted in decreased phosphorylation of FAK. Downstream of FAK, we observed reduced epithelial to mesenchymal transition, attenuated CDC42 expression, and decreased migration. Collectively, these results suggest that denatured collagen presents a novel target for modulating the tumor microenvironment and treating solid cancers via the LOX1/LOXL2-FAK signaling pathway.

Korean Liver Cancer Association (KLCA) and National Cancer Center (NCC) Korea. 2022 KLCA-NCC Korea practice guidelines for the management of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the fifth most common cancer worldwide and the fourth most common cancer among men in South Korea, where the prevalence of chronic hepatitis B infection is high in middle and old age. The current practice guidelines will provide useful and sensible advice for the clinical management of patients with HCC. A total of 49 experts in the fields of hepatology, oncology, surgery, radiology, and radiation oncology from the Korean Liver Cancer Association-National Cancer Center Korea Practice Guideline Revision Committee revised the 2018 Korean guidelines and developed new recommendations that integrate the most up-to-date research findings and expert opinions. These guidelines provide useful information and direction for all clinicians, trainees, and researchers in the diagnosis and treatment of HCC.

Comparison of Ablation Performance between Octopus Multipurpose Electrode and Conventional Octopus Electrode

OBJECTIVE

To compare Octopus multipurpose (MP) electrodes, which are capable of saline instillation and direct tissue temperature measurement, and conventional electrodes for radiofrequency ablation (RFA) in porcine livers in vivo.

MATERIALS AND METHODS

Sixteen pigs were used in this study. In the first experiment, RFA was performed in the liver for 6 minutes using Octopus MP electrodes (n = 15 ablation zones) and conventional electrodes (n = 12 ablation zones) to investigate the effect of saline instillation. The ablation energy, electrical impedance, and ablation volume of the two electrodes were compared. In the second experiment, RFA was performed near the gallbladder (GB) and colon using Octopus MP electrodes (n = 12 ablation zones for each) with direct tissue temperature monitoring and conventional electrodes (n = 11 ablation zones for each). RFA was discontinued when the temperature increased to > 60\xe2\x84\x83 in the Octopus MP electrode group, whereas RFA was performed for a total of 6 minutes in the conventional electrode group. Thermal injury was assessed and compared between the two groups by pathological examination.

RESULTS

In the first experiment, the ablation volume and total energy delivered in the Octopus MP electrode group were significantly larger than those in the conventional electrode group (15.7 ± 4.26 cm³ vs. 12.5 ± 2.14 cm³, p = 0.027; 5.48 ± 0.49 Kcal vs. 5.04 ± 0.49 Kcal, p = 0.029). In the second experiment, thermal injury to the GB and colon was less frequently noted in the Octopus MP electrode group than that in the conventional electrode group (16.7% [2/12] vs. 90.9% [10/11] for GB and 8.3% [1/12] vs. 90.9% [10/11] for colon, p < 0.001 for all). The total energy delivered around the GB (2.65 ± 1.07 Kcal vs. 5.04 ± 0.66 Kcal) and colon (2.58 ± 0.57 Kcal vs. 5.17 ± 0.90 Kcal) were significantly lower in the Octopus MP electrode group than that in the conventional electrode group (p < 0.001 for all).

CONCLUSION

RFA using the Octopus MP electrodes induced a larger ablation volume and resulted in less thermal injury to the adjacent organs compared with conventional electrodes.

Diaphragmatic hernia after radiofrequency ablation of liver metastases: a case report and review of the literature

A diaphragmatic hernia is the protrusion of abdominal tissues into the thoracic cavity secondary to a defect in the diaphragm. Reviewing the literature, we found only 44 references to diaphragmatic hernia secondary to percutaneous radiofrequency treatment. The vast majority of these cases were secondary to the treatment of hepatocellular carcinoma in segments V and VIII. Nevertheless, to date, this is the first reported case of diaphragmatic hernia after radiofrequency ablation of a liver metastasis from colorectal cancer. Complications secondary to diaphragmatic hernias are very diverse. The principal risk factor for complications is the contents of the hernia; when small bowel or colon segments protrude in the thoracic cavity, they can become incarcerated. Asymptomatic cases have also been reported in which the diaphragmatic hernia was discovered during follow-up. The pathophysiological mechanism is not totally clear, but it is thought that these diaphragmatic hernias might be caused by locoregional thermal damage. Given that most communications correspond to asymptomatic and/or treated cases, it is likely that the incidence is underestimated. However, due to the advent of percutaneous treatments, this complication might be reported more often in the future. Most cases are treated with primary herniorrhaphy, done with a laparoscopic or open approach at the surgeon's discretion; no evidence supports the use of one approach over the other. Nevertheless, it seems clear that surgery is the only definitive treatment, as well as the treatment of choice if complications develop. However, in asymptomatic patients in whom a diaphragmatic hernia is discovered in follow-up imaging studies, management should probably be guided by the patient's overall condition, taking into account the potential risks of complications (contents, diameter of the opening into the thoracic cavity …).

2022 KLCA-NCC Korea Practice Guidelines for the Management of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the fifth most common cancer worldwide and the fourth most common cancer among men in South Korea, where the prevalence of chronic hepatitis B infection is high in middle and old age. The current practice guidelines will provide useful and sensible advice for the clinical management of patients with HCC. A total of 49 experts in the fields of hepatology, oncology, surgery, radiology, and radiation oncology from the Korean Liver Cancer Association-National Cancer Center Korea Practice Guideline Revision Committee revised the 2018 Korean guidelines and developed new recommendations that integrate the most up-to-date research findings and expert opinions. These guidelines provide useful information and direction for all clinicians, trainees, and researchers in the diagnosis and treatment of HCC.

2022 KLCA-NCC Korea practice guidelines for the management of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the fifth most common cancer worldwide and the fourth most common cancer among men in South Korea, where the prevalence of chronic hepatitis B infection is high in middle and old age. The current practice guidelines will provide useful and sensible advice for the clinical management of patients with HCC. A total of 49 experts in the fields of hepatology, oncology, surgery, radiology, and radiation oncology from the Korean Liver Cancer Association-National Cancer Center Korea Practice Guideline Revision Committee revised the 2018 Korean guidelines and developed new recommendations that integrate the most up-to-date research findings and expert opinions. These guidelines provide useful information and direction for all clinicians, trainees, and researchers in the diagnosis and treatment of HCC.

Complications after Thermal Ablation of Hepatocellular Carcinoma and Liver Metastases: Imaging Findings

Tumour ablation is a strategy of treatment of hepatic tumours in patients with small hepatocellular carcinoma (HCC) (<3 cm) or in patients unfit for surgical resection. Moreover, tumor ablation can be used as an adjuvant therapy or may be used in association with resection in case of patients with poor functional liver disease. These types of treatment usually could be performed percutaneously under image guidance. The most clinically verified and used ablation modalities are Radiofrequency Ablation (RFA) and microwave ablation (MWA). However, despite both of them are considered minimally invasive techniques, they could be related to post-procedural complications. The International Working Group on Image-Guided Tumor and the Society of Interventional Radiology (SIR) identified major and minor post-ablative complications. Major complications, as vascular complications, occur in 2.2% to 3.1% of cases and include all the high risk pathological conditions which could increase the level of care or result in hospital admission or substantially prolonged hospital stay (SIR classifications C−E). Minor complications, as biliary complications, occur in 5% to 8.9% and include self-limiting conditions that are considered to be of low risk for the patient’s outcome. The purpose of this review is to summarise the main pathological ultrasound (US) and Computed Tomography (CT) findings, that may arise after ablative treatment. To simplify the analysis, the pathological pictures are divided according to the site of damage into vascular, biliary and extrahepatic complications.

Infectious complications related to radiofrequency ablation of liver tumors: The role of antibiotics

Background and aim

Prophylactic administration of antibiotics within 24 hours of surgery is recommended to reduce the risk of infection. We conducted a prospective study to compare the efficacy of single administration of antibiotics with a historical control of continuous administration of antibiotics for radiofrequency ablation (RFA) of malignant liver tumors.

Methods

Between February 1, 1999 and November 30, 2010, a total of 6,763 RFA treatments were performed in 2,355 patients, using a protocol with continuous administration of prophylactic antibiotics. On December 1, 2010, we began using a revised protocol with a single administration of prophylactic antibiotics, while continuing to use the old continuous administration protocol for patients who declined the new protocol. Interim analysis was performed to assess the safety of the single administration protocol. Thereafter, from April 1, 2012, all patients were treated using the new protocol. Risk factors for infectious complications of RFA were assessed using logistic regression.

Results

From December 2010 to March 2012, 766 RFA treatments were performed in 663 patients using the new antibiotic protocol. Infectious complications were observed following 4 of these treatments (0.52%). As the upper limit of the confidence interval (CI) resulting from a one-sided binomial test was exactly the prespecified limit of 1.0%, from April 2012 onwards, we treated all patients using the new protocol with single administration of prophylactic antibiotics. A total of 3,547 RFA treatments were performed using the single administration protocol. Univariable logistic regression indicated that prior transcatheter arterial chemoembolization (TACE) and maximal tumor diameter were significant risk factors for infectious complications (P = 0.04 and P < 0.001, respectively). Multivariable analysis indicated that the adjusted hazard ratio of single vs. continuous administration of antibiotics was 1.20 (95% CI: 0.53–2.75; P = 0.66).

Conclusions

The rate of infectious complications related to RFA was acceptably low. Single administration of prophylactic antibiotics did not significantly increase the rate of infectious complications related to RFA, compared with a more intensive antibiotic protocol.

Hemostasis using re-radiofrequency ablation for hepatic tract bleeding after ultrasound-guided percutaneous radiofrequency ablation of hepatic tumors

OBJECTIVE

To evaluate the hemostatic efficacy of re-radiofrequency ablation (re-RFA) for hepatic tract bleeding after ultrasound-guided RFA of hepatic tumors.

METHODS

A total of 4679 percutaneous ultrasound-guided RFA procedures were performed for hepatic tumors at Samsung Medical Center between January 2012 and December 2020. We identified patients who had hepatic tract bleeding after RFA by reviewing radiologic reports and ultrasound images and investigated the measures taken to control the bleeding and their outcomes. We also identified patients who had a significant peritoneal hematoma on immediate post-RFA CT or underwent transarterial embolization to control hepatic bleeding after RFA of hepatic tumors.

RESULTS

In total, 91 patients with tract bleeding after RFA were identified. As initial measures to control the bleeding, external compression, re-RFA, and observation were performed in 71 (78%), 17 (19%), and 3 (3%) patients, respectively. Hemostasis using re-RFA was attempted to control tract bleeding in 40 patients as an initial measure or an additional measure after other initial efforts. In all 40 patients, the bleeding stopped after re-RFA on Doppler ultrasound, and there was no active bleeding on the immediate follow-up CT. During the study period, in the years when re-RFA was performed frequently, the number of transarterial embolizations to control tract bleeding and significant peritoneal hematoma formation tended to be low.

CONCLUSION

Hemostasis using re-RFA of the needle tract is effective in controlling tract bleeding after ultrasound-guided RFA of hepatic tumors.

ADVANCES IN KNOWLEDGE

Re-RFA is a simple, safe, and effective method to control tract bleeding.

Ablation Zone Involution of Liver Tumors Is Faster in Patients Treated with Irreversible Electroporation Than Microwave Ablation

Background and Objectives: To compare ablation zone involution following microwave ablation (MWA) or irreversible electroporation (IRE) of liver tumors. Materials and Methods: MWA or IRE performed for colorectal cancer liver metastasis (CRLM) or hepatocellular carcinoma (HCC) during January 2011 to December 2015 were analyzed. Patients with a tumoral response on 1-year follow-up computed tomography (CT) were included. Generalized estimating equations were used to evaluate the differences between the two modalities on ablation zone involution observed on CT at 6 (M6) and 12 months (M12), and on laboratory values (total bilirubin, alanine transaminase, aspartate transaminase, alkaline phosphatase, albumin, and platelets count). The likelihood ratio test was used to assess whether the association between ablation modalities and these outcomes differed over time. Results: Seventeen (17/44, 39%) women and 27 (27/44, 61%) men were included, with 25 HCC (25/44, 57%) and 19 CRLM (19/44, 43%) patients. IRE was used in 9 (9/19, 47%) CRLM and 5 (5/25, 20%) HCC patients, respectively. All other patients had MWA. Ablation zone size and involution between IRE and MWA differed significantly over time (interaction p < 0.01), with a mean of 241.04 vs. 771.08 mm2 (ratio 0.313; 95% CI, 0.165-0.592; p < 0.01) at M6 and 60.47 vs. 589.43 mm2 (ratio 0.103; 95% CI, 0.029-0.365; p < 0.01) at M12. Changes in liver enzymes did not differ significantly between IRE and MWA at both timepoints. Conclusions: Liver tumors treated with IRE underwent faster involution when compared to tumors treated with MWA, but liver enzymes levels were comparable.

Role of Contrast-Enhanced Ultrasound in the Detection of Complications After Ultrasound-Guided Liver Interventional Procedures

The role of contrast-enhanced ultrasound (CEUS) in interventional ultrasound-guided procedures in the liver has been increasingly recognized. However, little is known about the capability of CEUS for diagnosing complications after liver biopsy and ablation with special regard to postprocedural hemorrhage. The aim of this Pictorial Essay is to present the CEUS features of a wide spectrum of vascular complications (with or without bleeding) and injuries of the surrounding abdominal and chest wall occurring after liver interventional procedures.

Radiofrequency ablation of surface v/s intraparenchymal hepatocellular carcinoma in cirrhotic patients

Objective

To retrospectively evaluate the safety and technical efficacy of percutaneous radiofrequency ablation (RFA) of surface hepatocellular carcinoma (HCC) in comparison to intraparenchymal HCC in cirrhotic patients.

Materials and Methods

Surface lesions were defined as tumours located or reaching within 1cm of liver capsule including exophytic lesions. Seventy-four surface HCC including 21 exophytic in 58 patients (surface group) and 60 intraparenchymal HCC in 54 patients (intraparenchymal group) measuring up to 4 cm in maximum extent underwent percutaneous [ultrasound (US) or computed tomography-guided (CT-guided)] RFA. The response to the treatment was assessed by contrast enhanced CT/magnetic resonance imaging (MRI) done at 1, 3, 6, 9, and 12 months of RFA and thereafter every 4-6 months. In case of features suggesting residual disease, a repeat RFA was performed. The technical success after single-session RFA, complications and disease recurrence rates were calculated and compared between two groups.

Results

Technical success achieved after first session of RFA in surface HCC was 95% (70/74) and intraparenchymal HCC was 97% (58/60). Hundred percent secondary success rate was achieved in both groups after second repeat RFA in residual lesion. No major difference in complication and local recurrence rate in both group on follow-up in surface HCC and intraparenchymal HCC. No case of needle track, peritoneal seeding, and treatment mortality was found.

Conclusions

The complication rate and efficacy of RFA for surface and exophytic HCC's were comparable to that of intraparenchymal HCC. Hence surface and exophytic lesions should not be considered a contraindication for RFA in cirrhotic patients.

Radiofrequency ablation versus stereotactic body radiation therapy for small (≤ 3 cm) hepatocellular carcinoma: A retrospective comparison analysis

BACKGROUND AND AIM

We compared the clinical outcomes of radiofrequency ablation (RFA) and stereotactic body radiation therapy (SBRT) in small (≤ 3 cm) hepatocellular carcinoma.

METHODS

A total of 266 patients treated with RFA (n = 179) or SBRT (n = 87) were reviewed. Local control rates (LCRs), intrahepatic recurrence-free survival (IHRFS) rates, and overall survival (OS) rates were compared. Inverse probability of treatment weighting (IPTW) was used to adjust for imbalances in baseline characteristics between the two groups.

RESULTS

The median follow-up period was 50.3 months, and treatment method (RFA vs SBRT) was not a significant prognostic factor for LCR, OS, and IHRFS in both multivariate and IPTW-adjusted analyses. The 4-year LCRs after RFA and SBRT were 92.7% and 95.0%, respectively. Perivascular location was a significant prognostic factor for LCR in the entire patients and in the RFA group, but not in the SBRT group. The 4-year OS rates in the RFA and SBRT groups were 78.1% and 64.1%, respectively (P = 0.012). After IPTW adjustment, the 4-year LCRs (90.6% vs 96.3%) and OS rates (71.8% vs 70.2%) were not significantly different between the two groups. The rate of grade ≥ 3 adverse events was 0.6% (n = 1) in the RFA group and 1.1% (n = 1) in the SBRT group.

CONCLUSIONS

The two treatment methods showed comparable outcomes in terms of LCR, OS rate, and IHRFS rate after IPTW adjustment. SBRT seems to be a viable alternative method for small hepatocellular carcinomas that are not suitable for RFA due to tumor location.

CT-guided biopsy of lung nodules with pleural contact: Comparison of two puncture routes

PURPOSE

The purpose of this study was to retrospectively compare two puncture routes (transpleural vs. transpulmonary) for computed tomography (CT) fluoroscopy-guided cutting needle biopsy of lung nodules with pleural contact.

PATIENTS AND METHODS

A total of 102 patients (72 men; mean age, 71.1±9.5 [SD] years) were included and 102 biopsies of 102 lung nodules (mean size, 16.7±5.9 [SD] mm; range, 6.0-29.4mm; mean length of pleural contact, 10.1±4.2 [SD] mm; range, 2.8-19.6mm) were analyzed. All procedures were classified as biopsies via the direct transpleural route or the transpulmonary route. The patient-, lesion-, and biopsy-related variables, diagnostic yields, and incidence of complications were compared between the two routes.

RESULTS

Biopsy was performed via the direct transpleural route (n=59; 57.8%) and transpulmonary route (n=43; 42.2%). In the transpulmonary route group, the mean distance of the intrapulmonary pathway was 17.7±9.4 [SD] mm (range: 4.1-47.6mm; P<0.001) and the introducer needle trajectory angle of<45° was significantly observed (8.5% [5/59] vs. 60.5% [26/43]; P<0.001). There was no significant difference in diagnostic accuracy between the direct transpleural and transpulmonary routes (93.2% [55/59] vs. 90.7% [39/43]; P=0.718). The frequencies of all complications (64.4% [38/59] vs. 97.7% [42/43]; P<0.001), pneumothorax (33.9% [20/59] vs. 65.1% [28/43]; P=0.003), pneumothorax with chest tube placement (3.4% [2/59] vs. 18.6% [8/43]; P=0.016), and pulmonary hemorrhage (47.5% [28/59] vs. 76.7% [33/43]; P=0.004) were significantly lower in the direct transpleural group.

CONCLUSION

Direct transpleural route is recommended for CT fluoroscopy-guided biopsy of lung nodules with pleural contact because it is safer and yields similar diagnostic accuracy than transpulmonary route.

Percutaneous Treatment of Bronchobiliary Fistula: Report of a Successful Transhepatic Embolization and a Decision-Making Strategy Driven by Systematic Literature Review

Bronchobiliary fistula is a rare condition characterized by bile leaking into the bronchial tree causing biliptysis. It may arise from liver infection or as a consequence of resection and thermal ablation of cancer. Currently, there is no consensus about the treatment strategy. Surgery is considered the main therapy by most authors. However, this systematic literature review shows that the success rate of percutaneous treatments may reach 75%. Adding to such evidence, we also report the case of a woman affected by iatrogenic bronchobiliary fistula secondary to liver thermal ablation, successfully treated with percutaneous drainage plus embolization. Summarizing these results, we encourage the percutaneous management of bronchobiliary fistula by providing a 3-step decision-making algorithm, aimed at reducing the need for major surgery.

Treatment trends and outcomes of hepatocellular carcinoma in a single center for 35 years

BACKGROUND

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer mortality. The aim of this study was to examine the trends of HCC treatment and the outcomes in a single tertiary center for 35 years.

METHODS

Two hundred seventy-three consecutive HCC patients between 1983-2018 were identified from Oulu University Hospital records. Primary outcomes of the study were postoperative complications within 30 days after the operation, and short- (30- and 90-day) and long-term (1, 3 and 5-year) survival.

RESULTS

Of the 273 patients, 49 underwent surgical resection, 25 local ablation, 48 angiological treatment and 151 had palliative treatment. The rate of surgery declined over time, while other invasive treatments increased. Major complications occurred in 14 (28.6%) patients after surgical resection, in 2 (8.0%) patients after local ablation and in 13 (27.1%) patients after angiological treatment (P=0.022). Recurrence and local recidives were observed especially in local ablation group and in angiological treatment group (P<0.001). Overall survival rates in surgical resection group were at 30 and 90 days, 1-, 3- and 5-years 95.9%, 95.9%, 85.1%, 59.0% and 51.2%. In local ablation group, respective overall survival rates were 100.0%, 100.0%, 86.1%, 43.1% and 18.8%, and in angiological group 95.8%, 93.6%, 56.1%, 26.3% and 6.6%. In cox regression model adjusted for confounding factors, mortality hazard was lowest after surgical resection. Prognosis was poor in palliative group.

CONCLUSIONS

Based on this Northern Finland population, the surgical resection of HCC has acceptable complication rate compared to other treatments; and yields the best long-term survival. Overall prognosis of HCC remains poor.

Laparoscopic repair of diaphragmatic hernia after radiofrequency ablation for hepatocellular carcinoma: Case report

•

Diaphragmatic hernia is a rare late-onset complication associated with RFA for HCC.

•

The tumor location is closely related to the risk of diaphragmatic hernia caused by RFA.

•

Patients with HCC often have severe liver dysfunction and cirrhosis.

•

Laparoscopic approach is safe and minimally invasive for severe cirrhosis patient.

•

The hernia gate was closed by suture, and vulnerable area was reinforced using mesh.

Introduction and importance

We describe the case of a patients with a diaphragmatic hernia associated with radiofrequency ablation for hepatocellular carcinoma who was treated by laparoscopic repair.

Case presentation

An 82-years-old man with history of HCC with hepatitis C virus-related liver cirrhosis (Child-Pugh B). The patient was treated RFA to HCC for segment 4, 5, 6, 8.

After 16 months from latest RFA for segment 8, the patient was admitted to our hospital because of mild dyspnea. Computed tomography revealed a diaphragmatic herniation of bowel loops into the right thoracic cavity. The patients electively underwent laparoscopic repair of the diaphragmatic hernia. The patient was discharged from hospital without any post-operative complications.

Clinical discussion

The only treatment to diaphragmatic hernia is surgery, but liver cirrhosis patients limits this possibility. For the surgical treatment of patients with severe cirrhosis, the operation should be carefully assessed. We believe that a laparoscopic approach should be used for repairing diaphragmatic hernia. In the present case, we considered that a laparoscopic approach was safer and more feasible than open laparotomy.

Conclusion

Diaphragmatic hernia is a rare late-onset complication associated with RFA for HCC. And patients with HCC often have severe liver dysfunction and cirrhosis. A laparoscopic approach is safe and minimally invasive for sever cirrhosis patients.

Comparative Analysis of Radiofrequency Ablation and Microwave Ablation for Critically Located Hepatocellular Carcinomas Smaller than 5 cm

Purpose To compare the safety and efficacy of radiofrequency ablation (RFA) versus microwave ablation (MWA) for hepatocellular carcinomas (HCC) smaller than 5 cm in critical locations.

Methods Single-center retrospective study of all patients who underwent RFA/MWA for HCC from July 2015 to Dec 2019. Critical location includes exophytic tumors, tumors ≤ 5 mm from the diaphragm, heart, gallbladder, kidney, gastrointestinal tract, and ≤ 10 mm from large vessels with caliber of ≥ 3 mm. Treatment effectiveness, local tumor progression, and complication rates were evaluated.

Results Out of 119 patients with 147 HCC nodules in critical location, 65 (M:F = 49:16; mean age–61.7) were included in RFA group and 54 (M:F =43:11; mean age–60.5) in MWA group. Mean follow-up period was 16.5 and 14.8 months, respectively. At first follow-up imaging, 66/78 tumors in RFA group and 57/69 tumors in MWA group showed complete ablation with primary treatment effectiveness rates of 84.6% and 82.6%, respectively (p = 0.741). Local tumor progression (LTP) rate was 21.8% (17/78) and 20.3% (14/69), respectively (p = 0.826). Median time to LTP was 12 and 13.5 months, respectively. Fourteen tumors in RFA group and 12 in MWA group underwent reablation with a secondary treatment effectiveness rates of 78.6% (14/17) and 83.3% (12/14), respectively (p = 0.757). Mean LTP-free survival was 37.2 and 28.1 months, respectively. The total complication rate was 36.9% and 31.5%, respectively (p = 0.535) with no major complications in both the groups.

Conclusion Our data suggest that both MWA and RFA are equally safe and effective for treating HCCs < 5 cm in critical locations.

Reducing Pain by Artificial Ascites Infusion During Radiofrequency Ablation for Subcapsular Hepatocellular Carcinoma

PURPOSE

To evaluate therapeutic effects of artificial ascites (AA) infusion in patients with subcapsular hepatocellular carcinoma (HCC) treated with radiofrequency ablation (RFA) and to determine whether this infusion can reduce pain.

METHODS AND MATERIALS

From 2011 to 2016, 123 patients with treatment-naïve single subcapsular HCC (≤ 2.5 cm) who underwent RFA were retrospectively included. Patients were divided into two groups according to AA infusion. After RFA, medical records were used to analyze pain scores during a 24-h period and to determine the opioid used that compared using Mann-Whitney U test. We also conducted subgroup analysis of the patients with HCCs located adjacent to parietal peritoneum. After follow-up period, we analyzed local tumor progression (LTP) and recurrence-free survival using Kaplan-Meier method.

RESULTS

AA was infused in 76 patients (61.8%, 76/123). Pain score using numeric rating scale (NRS) was significantly lower in AA infusion group than in control group (2.54 ± 2.8 vs. 3.66 ± 3.2, p = 0.048). Dose of opioids used was not significantly different between two groups (1.62 ± 3.4 mg vs. 1.66 ± 3 mg, p = 0.698). However, in subgroup analysis (N = 45), NRS score and dose of opioids used were significantly lower in AA infusion group (p = 0.03, p = 0.032, respectively). LTP rate was not significantly different between two groups (p = 0.673).

CONCLUSION

AA infusion was an effective and safe way to reduce pain when performing RFA for subcapsular HCC. In particular, in patients with subcapsular HCC adjacent to parietal peritoneum, dose of opioid to use pain control was significantly lower with AA infusion.

Radiomic analysis of MRI to Predict Sustained Complete Response after Radiofrequency Ablation in Patients with Hepatocellular Carcinoma - A Pilot Study

OBJECTIVES

To investigate whether quantitative textural features, extracted from pretreatment MRI, can predict sustained complete response to radiofrequency ablation (RFA) in patients with hepatocellular carcinoma (HCC).

METHODS

In this IRB-approved study, patients were selected from a maintained six-year database of consecutive patients who underwent both pretreatment MRI imaging with a probable or definitive imaging diagnosis of HCC (LI-RADS 4 or 5) and loco-regional treatment with RFA. An experienced radiologist manually segmented the hepatic nodules in MRI arterial and equilibrium phases to obtain the volume of interest (VOI) for extraction of 107 quantitative textural features, including shape and first- and second-order features. Statistical analysis was performed to evaluate associations between textural features and complete response.

RESULTS

The study consisted of 34 patients with 51 treated hepatic nodules. Sustained complete response was achieved by 6 patients (4 with single nodule and 2 with multiple nodules). Of the 107 features from the arterial and equilibrium phases, 20 (18%) and 25 (23%) achieved AUC >0.7, respectively. The three best performing features were found in the equilibrium phase: Dependence Non-Uniformity Normalized and Dependence Variance (both GLDM class, with AUC of 0.78 and 0.76, respectively) and Maximum Probability (GLCM class, AUC of 0.76).

CONCLUSIONS

This pilot study demonstrates that a radiomic analysis of pre-treatment MRI might be useful in identifying patients with HCC who are most likely to have a sustained complete response to RFA. Second-order features (GLDM and GLCM) extracted from equilibrium phase obtained highest discriminatory performance.

Transarterial Yttrium-90 Radioembolization of Hepatocellular Carcinoma Perfused by the Cystic Artery: Multi-institutional Feasibility Study

PURPOSE

To assess the safety and efficacy of transarterial yttrium-90 radioembolization via the cystic artery for patients with hepatocellular carcinoma (HCC) adjacent to the gallbladder with cystic artery supply.

MATERIALS AND METHODS

This retrospective study included 17 patients treated at 4 institutions. Patients with HCC perfused by the cystic artery who received ablative-dose radioembolization were included. Median tumor size was 3.8 cm (range, 2.0-8.8 cm). Fourteen patients (82%) had Child-Pugh class A cirrhosis and 3 (18%) had class B cirrhosis. Adverse events, tumor response, and time to progression were analyzed.

RESULTS

Median dose to the tissue perfused by the cystic artery was 340 Gy (range, 200-720 Gy). There were no occurrences of acute cholecystitis warranting invasive intervention. Four patients (24%) experienced transient right upper quadrant pain, with symptom resolution within 3 mo. Six patients (35%) exhibited gallbladder wall edema on follow-up imaging. Two (12%) and 0 grade 3/4 increases in alkaline phosphatase and bilirubin were observed, respectively. Follow-up imaging demonstrated complete response in 13 target tumors (76%) and partial response in 4 (24%). There were no cases of target tumor progression during a median follow-up of 9 mo (range, 3-72 mo).

CONCLUSIONS

Direct infusion of 90Y microspheres via the cystic artery appears to have an acceptable safety profile, without resulting in acute cholecystitis warranting invasive intervention. In selected patients with HCC in whom other treatments may be contraindicated and the tumor is supplied via the cystic artery, treatment with selective ablative radioembolization can be considered.

Mycotic pseudoaneurysm of the hepatic artery as a complication of radiofrequency ablation of hepatic metastases

Image-guided radiofrequency ablation is frequently used to treat small hepatocellular carcinoma and metastases. Complications associated with this thermal-based technology for liver cancers arise via direct mechanical injury by the electrodes or collateral thermal damage to surrounding structures. This case report describes an unusual presentation of hepatic arterial mycotic pseudoaneurysm as melaena after percutaneous image-guided radiofrequency ablation for liver metastases in a patient with a previous surgical history of hepaticojejunostomy for cholangiocarcinoma. The patient had a lifesaving procedure to treat the hepatic pseudoaneurysm with transarterial glue embolization.

Factors Associated With Local Tumor Control and Complications After Thermal Ablation of Colorectal Cancer Liver Metastases: A 15-year Retrospective Cohort Study

INTRODUCTION

The purpose of this study was to identify risk factors associated with local tumor progression-free survival (LTPFS) and complications after colorectal liver metastases (CLM) thermal ablation (TA).

PATIENTS AND METHODS

This retrospective analysis included 286 patients with 415 CLM undergoing TA (radiofrequency and microwave ablation) in 378 procedures from January 2003 to July 2017. Prior hepatic artery infusion (HAI), bevacizumab, pre-existing biliary dilatation, ablation modality, minimal ablation margin (MM), prior hepatectomy, CLM number, and size were analyzed as factors influencing complications and LTPFS. Statistical analysis included the Kaplan-Meier method, Cox proportional hazards model, competing risk analysis, univariate/multivariate logistic/exact logistic regressions, and the Fisher exact test. Complications were reported according to modified Society of Interventional Radiology guidelines.

RESULTS

The median follow-up was 31 months. There was no LTP for MM > 10 mm. Smaller tumor size, increased MM, and prior hepatectomy correlated with longer LTPFS. The major complications occurred following 28 (7%) of 378 procedures. There were no biliary complications in HAI-naive patients, versus 11% in HAI patients (P < .001), of which 7% were major. Biliary complications predictors in HAI patients included biliary dilatation, bevacizumab, and MM > 10 mm. In HAI patients, ablation with 6 to 10 mm and > 10 mm MM resulted in major biliary complication rates of 4% and 21% (P = .0011), with corresponding LTP rates of 24% and 0% (P = .0033). In HAI-naive patients, the LTP rates for 6 to 10 mm and > 10 mm MM were 27% and 0%, respectively.

CONCLUSIONS

No LTP was seen for MM > 10 mm. Biliary complications occurred only in HAI patients, especially in those with biliary dilatation, bevacizumab, and MM > 10 mm. In HAI patients, MM of 6 to 10 mm resulted in 76% local tumor control and 4% major biliary complications incidence.

Gastrointestinal tract injuries after thermal ablative therapies for hepatocellular carcinoma: A case report and review of the literature

BACKGROUND

Radiofrequency ablation (RFA) and microwave ablation (MWA) represent the standard of care for patients with early hepatocellular carcinoma (HCC) who are unfit for surgery. The incidence of reported adverse events is low, ranging from 2.4% to 13.1% for RFA and from 2.6% to 7.5% for MWA. Gastrointestinal tract (GIT) injury is even more infrequent (0.11%), but usually requires surgery with an unfavourable prognosis. Due to its low incidence and the retrospective nature of the studies, the literature reporting this feared complication is heterogeneous and in many cases lacks information on tumour characteristics, comorbidities and treatment approaches.

CASE SUMMARY

A 77-year-old man who had undergone extended right hepatectomy for HCC was diagnosed with early disease recurrence with a small nodule compatible with HCC in the Sg4b segment of the liver with a subcapsular location. He was treated with percutaneous RFA and a few week later he was urgently admitted to the Surgery ward for abdominal pain and fever. A subcutaneous abscess was diagnosed and treated by percutaneous drainage. A fistulous tract was then documented by the passage of contrast material from the gastric antrum to the abdominal wall. The oesophagogastroduodenoscopy confirmed a circular wall defect at the lesser curvature of gastric antrum, leading directly to the purulent abdominal collection. An over-the-scope clip (OTSC) was used to successfully close the defect.

CONCLUSION

This is the first reported case of RFA-related GIT injury to have been successfully treated with an OTSC, which highlights the role of this endoscopic treatment for the management of this complication.

Outcome of Laparoscopic Assisted Percutaneous Microwave Ablation for Exophytic Versus Non-exophytic Hepatocellular Carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is one of the most common malignancies and is the third cause of cancer-related death worldwide. Surgery is the optimal treatment for early HCC; however, the majority of cases are not suitable for curative resection at the time of diagnosis. Surgical resection difficulties may be related to size, site, number of tumors, extrahepatic involvement, and patient general condition. Exophytic tumors were considered as relative contraindication for thermal ablation because of the risk of incomplete ablation or major complications as hemorrhage and seeding.

AIM OF THIS STUDY

to evaluate the safety and efficacy of microwave ablation (MWA) of exophytic HCC in comparison with non-exophytic HCC.

METHODS

Prospective comparative study carried on 30 patients having 30 exophytic (six of those patients had another non-exophytic lesion) and 32 patients having 44 non-exophytic HCC lesions (22 had single lesion, 8 patients had 2 lesions, and 2 patients had 3 lesions) within Milan criteria. All patients were child A or B, they were subjected to full clinical assessment, laboratory investigations, and radiological investigations. Laparoscopic assisted percutaneous MWA was the procedure of choice in our study for all patients either having exophytic or non-exophytic lesions using no-touch wedge technique for exophytic lesions and direct puncture for non-exophytic lesions.

RESULTS

Technical success was 100% in both groups, all lesions were completely ablated as confirmed by LIOUS. There were no major complications or perioperative mortality and low incidence of local tumor progression in both exophytic and non-exophytic groups.

CONCLUSION

Laparoscopic assisted MWA of exophytic HCC is safe and effective with comparable results to non-exophytic HCC. Exophytic HCC is not contraindication for MWA with proper technique selection.

Radiofrequency Ablation Using a Separable Clustered Electrode for the Treatment of Hepatocellular Carcinomas: A Randomized Controlled Trial of a Dual-Switching Monopolar Mode Versus a Single-Switching Monopolar Mode

OBJECTIVE

This study aimed to prospectively compare the efficacy, safety, and mid-term outcomes of dual-switching monopolar (DSM) radiofrequency ablation (RFA) to those of conventional single-switching monopolar (SSM) RFA in the treatment of hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

This single-center, two-arm, parallel-group, randomized controlled study was approved by the Institutional Review Board. Written informed consent was obtained from all patients upon enrollment. A total of 80 patients with 94 HCC nodules were randomized into either the DSM-RFA group or SSM-RFA group in a 1:1 ratio, using a blocked randomization method (block size 2). The primary endpoint was the minimum diameter of the ablation zone per unit time. The secondary endpoints included other technical parameters, complication rate, technique efficacy, and 2-year clinical outcomes.

RESULTS

Significantly higher ablation energy per unit time was delivered to the DSM-RFA group than to the SSM-RFA group (1.7 ± 0.2 kcal/min vs. 1.2 ± 0.3 kcal/min; p < 0.001). However, no significant differences were observed between the two groups for the analyzed variables, including primary endpoint, regarding size of the ablation zone and ablation time. Major complication rates were 4.9% in the DSM-RFA group and 2.6% in the SSM-RFA group (p = 1.000). The 2-year local tumor progression (LTP) rates of the HCC nodules treated using DSM-RFA and SSM-RFA were 8.5% and 4.7%, respectively (p = 0.316). The 2-year LTP-free survival rates of patients in the DSM-RFA and SSM-RFA groups were 90.0% and 94.4%, respectively (p = 0.331), and the 2-year recurrence-free survival rates were 54.9% and 75.7%, respectively (p = 0.265).

CONCLUSION

Although DSM-RFA using a separable clustered electrode delivers higher ablation energy than SSM-RFA, its effectiveness failed to show superiority over SSM-RFA in the treatment of HCC.

Anticoagulation status post radiofrequency ablation in a patient with hepatocellular carcinoma and delayed bleeding event

Restarting anticoagulation is a tricky component of patient care. This is a case of a 65-year-old female presenting with hepatocellular carcinoma. A nonocclusive thrombus in the main portal vein was also identified. Six days postradiofrequency ablation (RFA), the patient's hemoglobin dropped to critical values and noncontrast computed tomography of the abdomen/pelvis revealed high density free fluid consistent with a bleed. The patient was medically managed and accepted for transfer to another hospital for IR-guided TIPS procedure. Patient recovered without any other complications. In conclusion, VTE prophylaxis be routinely initiated immediately following hepatectomy in hemodynamically stable patients without signs of active bleeding and should bleeding occur halt source then restart anticoagulation immediately.

Bronchobiliary fistula after ablation of hepatocellular carcinoma adjacent to the diaphragm: Case report and literature review

Background

Bronchobiliary fistula is a rare, but life‐threatening complication after ablation of hepatocellular carcinoma. Few cases of bronchobiliary fistula have been reported and the treatment is controversial.

Methods

From 2006 to 2019, a total of 11 patients were diagnosed with bronchobiliary fistula after ablation and received nonsurgical treatment.

Results

All 11 patients presented with cough and bilioptysis. There were only two patients in which MRI revealed an obvious fistulous tract connecting the pleural effusion and biliary lesions. Pleural effusion, liver abscess and hepatic biloma were found in other patients. Three patients died of uncontrolled bronchobiliary fistula.

Conclusions

Bronchobiliary fistula is a rare post‐ablation complication but should be taken into consideration in clinical decisions. Minimally invasive interventional treatment is a relatively effective means of dealing with bronchobiliary fistula, but as for the more severe cases, greater clinical experience is required.

Risk factors of intrahepatic biloma and secondary infection after thermal ablation for malignant hepatic tumors

Objective: This study aimed to evaluate the risk factors of biloma formation and secondary infection after thermal ablation for malignant hepatic tumors. Patients and methods: A total of 58 patients with 68 bilomas after thermal ablation were recruited as the complication group, and 61 patients with 72 lesions without major complications were selected randomly as the control group. The potential risk factors for biloma formation were analyzed with the chi-square test and multivariate logistic regression analysis. To determine the optimum management method for biloma, patients with secondary infection were included for the subgroup analysis of risk factors. Results: A history of transcatheter arterial chemoembolization (TACE) treatment (odds ratio [OR]: 3.606, 95% confidence interval [CI]: 1.165-11.156, p = .026) and tumor location (OR: 37.734, 95% CI: 13.058-109.034, p = .000) were independent predictors of biloma formation. Among the 58 patients with biloma, 49 (84.5%) showed no symptoms (i.e., the asymptomatic group), while the remaining 9 (15.5%) developed symptoms related to secondary infections (i.e., the symptomatic group). There were significant differences in the history of biliary manipulation (p = .031) between the symptomatic and asymptomatic groups. Conclusion: A history of TACE treatment and the distance from the biliary tract were independent predictors of biloma formation after thermal ablation. Therefore, protecting the bile duct (i.e., cooling of the bile duct and combing thermal ablation with chemical ablation) should be considered for high-risk patients. Moreover, active monitoring and management should be performed for patients with bilomas who underwent biliary surgery before.

Complications after Radiofrequency Ablation for Hepatocellular Carcinoma: A Multicenter Study Involving 9,411 Japanese Patients

INTRODUCTION

Radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC) is considered a safe and minimally invasive procedure. We previously reported that the mortality and complication rates for RFA were 0.038% (5/13,283 patients) and 3.54% (579 complications/16,346 procedures), respectively, from 1999 to 2010 (previous period). In this study, we investigated the clinical criteria for RFA and the mortality and complication rates from 2011 to 2015 (recent period).

METHODS

Data were collected from 25 centers by using a questionnaire developed by the Chugoku-Shikoku Society for Local Ablation Therapy of HCC. The criteria for RFA, RFA modification, use of image-guidance modalities, mortality, and complications during the previous and recent periods were compared.

RESULTS

We evaluated 11,298 procedures for 9,411 patients, including those that involved new devices (bipolar RFA and internally adjustable electrode system). The criterion of hepatic function for RFA increased from a Child-Pugh score ≤8 during the previous period to ≤9 during the recent period. The criteria regarding the tumor location and other risk factors have been expanded recently because of the increased use of several modifications of the RFA procedure and image-guidance modalities. The mortality rate was 0.064% (6/9,411 patients), and the complication rate was 2.92% (330 complications/11,298 procedures). There was no difference in mortality rates between the 2 periods (p = 0.38), but the complication rates was significantly lower during the recent period (p = 0.038).

DISCUSSION AND CONCLUSIONS

Our findings confirmed that RFA, including the use of new devices, is a low-risk procedure for HCC, despite the expansion of the criteria for RFA during the recent period.

Percutaneous portal vein embolization for intractable hepatic biloma after radiofrequency ablation

Intrahepatic biloma is a rare complication of radiofrequency ablation (RFA). When present, it can only be conservatively managed. Here, we report the case of a patient with hepatocellular carcinoma complicated by an intractable biloma after RFA. The biloma could not be managed via percutaneous catheter drainage and antibiotic administration for over 3 months. The intractable biloma was finally cured using percutaneous transhepatic portal vein embolization. The present case demonstrates a useful treatment option for intractable biloma after RFA.

Percutaneous Radiofrequency Ablation for Liver Tumors: Technical Tips

Percutaneous radiofrequency ablation (RFA) has been accepted as a minimally invasive therapeutic treatment for liver malignancies. Although RFA is usually applied for the treatment of small liver tumors (<3 cm), several technical developments have expanded the use of RFA. RFA is now used for the treatment of large liver tumors, and the number of complications associated with this treatment has decreased. These refinements may ultimately lead to better long-term prognosis. Here, we review recent refinements of liver RFA and provide technical tips.

Percutaneous thermal ablation of subcapsular hepatocellular carcinomas: influence of tumor-surface contact and protrusion on therapeutic efficacy and safety

PURPOSE

To evaluate therapeutic efficacy and complication of percutaneous thermal ablation of subcapsular hepatocellular carcinomas (HCCs), and how these may be influenced by the degree of tumor to liver surface contact and tumor protrusion from liver surface.

MATERIALS AND METHODS

Our retrospective study was approved by the Institutional Review Board. Between January 2006 and December 2013, 290 patients (82 women, 208 men; mean age, 64.5 years; range, 33-89 years) with 474 subcapsular (within 1 cm to the liver surface) HCCs (mean size, 23.7 mm; range, 6-71 mm) underwent percutaneous thermal ablation. The HCCs were divided into surface contact group (n = 243) and non-surface contact group (n = 231). The former was further subdivided into exophytic and non-exophytic HCCs. Technical success, primary technique efficacy, local tumor progression (LTP), and secondary technique efficacy rates were analyzed and compared by the chi-square test or Fisher exact test. Prognostic factors for LTP and secondary technique efficacy were assessed using the Cox regression model. Major complications were also assessed.

RESULTS

With median follow-up of 15 months (range, 1-87 months), technical success and primary technique efficacy were 98.7% and 95.7% % in the non-surface contact group; 96.4% and 94.0% in the non-exophytic group; and 100% and 94.7% in the exophytic group (p > 0.05). Tumor size > 3 cm was a significant predictor for LTP, but not for secondary efficacy. Overall major complication rate was 3.8% (24/624) and was not different among the three groups.

CONCLUSION

Subcapsular HCCs can be effectively treated with thermal ablation techniques. Degree of tumor-surface contact including moderate protrusion does not appear to limit feasibility or procedure effectiveness.

KEY POINTS

• Subcapsular HCCs can be effectively treated with thermal therapy when proper image-guided technique and assistive techniques are applied. • Degree of tumor surface contact including moderate protrusion does not appear to limit feasibility or procedure effectiveness. • Major complications after percutaneous thermal ablation of subcapsular HCCs such as tumor seeding can be minimized by avoiding breach of the tumor capsule exposed to the peritoneal surface and use of tract ablation.

Treatment of a huge biloma complicating curative radiofrequency ablation of hepatocellular carcinoma: a case report

Development of a huge intrahepatic biloma after radiofrequency ablation (RFA) is a rare complication. We report a patient with hepatocellular carcinoma (HCC) who had been treated by RFA and was complicated by a huge biloma. The biloma was cured by percutaneous catheter drainage and endoscopic retrograde cholangiopancreatography. A plastic stent was placed from the duodenal ampulla to the common bile duct to lower the pressure. The catheter and the stent were removed within 1 month after the biloma had disappeared. There was no recurrence of the biloma and HCC lesions with a follow-up time of 2 years. The present case is one of the best reported outcomes after development of a huge biloma.

Current status of stereotactic body radiotherapy for the treatment of hepatocellular carcinoma

Stereotactic body radiotherapy (SBRT) is an advanced form of radiotherapy (RT) with a growing interest on its application in the treatment of hepatocellular carcinoma (HCC). It can deliver ablative radiation doses to tumors in a few fractions without excessive doses to normal tissues, with the help of advanced modern RT and imaging technologies. Currently, SBRT is recommended as an alternative to curative treatments, such as surgery and radiofrequency ablation. This review discusses the current status of SBRT to aid in the decision making on how it is incorporated into the HCC management.

Contrast-enhanced US in Local Ablative Therapy and Secondary Surveillance for Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) has a high incidence of recurrence following therapy. Therefore, secondary surveillance (scheduled follow-up imaging after treatment) is an important part of disease management. The recent approval in the United States for use of a microbubble-based contrast agent for US liver imaging promotes the increased use of contrast-enhanced US (CEUS) in patients with HCC. Although the criteria for the diagnosis of HCC at CEUS are well described, there is a paucity of published literature describing the role of CEUS in ablative therapy and secondary surveillance. In the setting of ablative therapy, CEUS can have vital roles, including patient selection, intraprocedural guidance, and immediate postprocedural assessment. Although CEUS is not widely used, the authors found that it can be used to accurately detect residual or recurrent tumor, characterize the geographic pattern of recurrence (intrazonal, extrazonal, segmental, or remote), and assess for tumor in vein. In addition, similar to primary surveillance, secondary surveillance includes assessment of the entire liver for evaluation of new nodules. Arterial phase hyperenhancement is the reference standard characteristic of disease recurrence at secondary surveillance with CEUS. ^©RSNA, 2019 See discussion on this article by Rodgers.