Percutaneous microwave ablation vs radiofrequency ablation in the treatment of hepatocellular carcinoma

Embolic and Ablative Therapy for Hepatocellular Carcinoma

Embolic and ablative locoregional therapies (LRTs) for hepatocellular carcinoma are widely used to cure, bridge, or downstage patients for more definitive therapies. Common ablative therapies include microwave ablation and radiofrequency ablation, while embolic options include transarterial chemoembolization and 90Y transarterial radioembolization. While these therapies can be highly effective for the appropriate stage of disease, LRTs can suffer from a high rate of posttreatment recurrences. Considerations for administration of specific therapies include disease burden and underlying liver function. Recent data on concomitant or adjuvant systemic therapy, with LRT, have the potential to improve disease control and improve outcomes in this high-risk patient population.

Minimally Invasive Image-Guided Percutaneous Irreversible Electroporation of Adrenal Metastases

PURPOSE

A single-center retrospective study was performed to evaluate the safety and efficacy of minimally invasive irreversible electroporation (IRE) to treat metastatic adrenal tumors.

MATERIALS AND METHODS

This single-center study, approved by the Institutional Review Board, retrospectively analyzed six patients who underwent image-guided percutaneous IRE for adrenal metastases. Pre-procedural imaging included CT, MRI and/or 18F-FDG PET-CT scans. Primary outcomes measures included technical success, efficacy and safety, while secondary outcome measures were local progression-free survival (LPFS), distant progression-free survival (DPFS) and overall survival (OS). Follow-up scans were scheduled post-procedure, and data analysis employed Excel, SPSS and R.

RESULTS

Patients had diverse primary tumor origins including renal cell carcinoma (2/6), colorectal carcinoma (1/6), non-small cell lung carcinoma (1/6), leiomyosarcoma (1/6) and urothelial carcinoma (1/6). Adverse events were minimal, with only one grade 1 complication reported. Tumor characteristics revealed tumors close to critical structures, with a median pre-ablation size of 23 mm. Technical success was achieved in all procedures. At first follow-up, one patient had complete response, one patient had partial response of the right adrenal gland and complete response of the left adrenal gland, two patients had partial response and two patients had stable disease. Local tumor progression occurred in two out of seven tumors with a median LPFS of 10.9 months, and distant progression was observed in four out of six patients.

CONCLUSION

Percutaneous, minimally invasive IRE shows promise as a safe treatment option for unresectable metastatic adrenal tumors, demonstrating potential effectiveness. However, further studies with larger patient cohorts are needed to confirm its safety and efficacy.

Development and management of iatrogenic biloma post microwave ablation of solitary metastatic breast cancer lesion in the liver

Thermal ablation is used to treat liver metastasis including those from breast cancer. The ablation is associated with pain, hemorrhage, and biliary structure damage leading to bilomas. Biloma is a collection of bile that can occur inside or outside the biliary system, which could happen as a rare complication of surgery (from procedures like abdominal surgery or diagnostic procedures), trauma, or spontaneously. We report a case of biloma development after microwave ablation (MWA) of a metastatic lesion in the liver. We present a 66-year-old female diagnosed with stage 4 intraductal carcinoma of the right breast with metastasis to the liver. She developed biloma and infarction of the left lobe of the liver following MWA, which was treated with percutaneous internal/external biliary drain placement. Her symptoms and liver function tests were completely resolved after 3 months, and her left hepatic lobe completely atrophied in the same period. Biloma is a rare but concerning complication of MWA, therefore high suspicion should be maintained in patients presenting with cholestatic symptoms and fever postprocedure. When identified, drainage with antibiotic therapy can effectively treat biloma and resolve the symptoms.

The Efficacy and Safety of a Microwave Ablation System with a Dipole Antenna Design Featuring Floating Sleeves and Anti-Phase Technology in Stereotactic Percutaneous Liver Tumor Ablation: Results from a Prospective Study

Purpose: To evaluate the efficacy and safety of the Surgnova Dophi™ M150E microwave ablation system in a prospective single-center observational study. Methods: A cohort of 50 patients with 77 primary or secondary liver tumors underwent CT-navigated stereotactic percutaneous microwave ablation with curative intention using the Surgnova Dophi™ M150E system. The endpoints were primary technique efficacy (PTE), number of complications, ablation defect dimensions, and sphericity index compared to previously reported findings. Results: The PTE was 97.4%, with complete ablation in 75 out of 77 tumors. Complications occurred in 10% of patients, with 4% classified as major. A comparison with previous in vivo data confirmed the reliability of the system in achieving reproducible and predictable ablation results. Conclusions: Stereotactic percutaneous microwave ablation with the Surgnova Dophi™ M150E system is safe and effective for liver tumor treatment.

Percutaneous microwave ablation of HCC: comparison between 100 and 150 W technology systems

PURPOSE

To evaluate the differences in efficacy and safety between the 100 and 150 W percutaneous microwave ablation (MWA) systems in the treatment of hepatocellular carcinoma (HCC).

METHODS

We retrospectively reviewed all patients who underwent percutaneous MWA (Emprint™ HP Ablation System, Medtronic) between January 2021 and May 2023. We divided the cohort into two groups: Group 1, treated with MWA at 100 W power system, and Group 2, treated with 150 W one. Effectiveness was defined as the absence of residual disease at 1-month CT follow-up; safety was defined as the absence of grade II-VI complications.

RESULTS

A total of 135 HCC nodules were treated with MWA in 87 patients with a median age of 66 ± 10 years: 76 procedures in 42 patients were carried out in group 1, while 59 procedures in 45 patients in group 2. Cases treated with 150 W had a shorter ablation time (p: 0.002; mean 227.37 ± 92.5 vs 180.51 ± 75.6 s (100 vs 150 W)) and a larger ablation volume (p 0.008; mean 13,920.0 ± 10,723.2 vs 21,241.4 ± 18,374.7 mm3 (100 vs 150 W)), and a major effectiveness at 1-month CT follow-up (p: 0.013). A higher rate of complications (grade II and III) was observed in Group 2 (p < 0.001).

CONCLUSIONS

In conclusion, these preliminary results showed a good correlation between intended-to-treat area and ablation volume and intended-to-treat area and ablation time for both Groups. A minor ablation time, and major ablation volume, but also a higher incidence of complications was observed in 150 W Group.

Transarterial chemoembolization combined with microwave ablation versus repeated resection for recurrent small hepatocellular carcinoma after resection: What is the better treatment?

PURPOSE

This study aimed to compare the effectiveness of transcatheter arterial chemoembolization combined with microwave ablation (TACE-MWA) versus repeated hepatic resection (RHR) in patients with recurrent small hepatocellular carcinoma (sHCC) following primary resection.

MATERIALS AND METHODS

A total of 59 patients diagnosed with recurrent sHCC (≤3 cm) and treated with either TACE-MWA or RHR were recruited from two centers between June 2015 and October 2021. Patients were matched using propensity scores at a 1:1 ratio. Disease-free survival (DFS), overall survival (OS), and complications were assessed and compared between the two treatment groups.

RESULTS

After propensity score matching, 38 patients were included, with 19 in each group. Prior to matching, the 1-, 3-, and 5-year DFS rates for the TACE-MWA group were 68.1%, 46.6%, and 23.3%, respectively, and for the RHR group, they were 84.6%, 47.3%, and 47.3%, respectively. The corresponding 1-, 3-, and 5-year OS rates for TACE-MWA were 100.0%, 83.7%, and 47.8%, while for RHR, they were 100.0%, 95.0%, and 45.2%. After matching, the 1-, 3-, and 5-year DFS rates were 78.0%, 48.3%, and 24.1% for TACE-MWA, and 77.5%, 38.7%, and 38.7% for RHR. The 1-, 3-, and 5-year OS rates for TACE-MWA were 100.0%, 88.9%, and 54.9%, and for RHR, they were 100.0%, 93.3%, and 44.4%. Statistical analysis showed no significant differences in DFS rates (P=0.834 before matching, P=0.490 after matching) or OS rates (P=0.825 before matching, P=0.625 after matching) between the two groups.

CONCLUSIONS

TACE-MWA demonstrates comparable effectiveness to RHR in managing recurrent sHCC.

Comparative Efficacy of Microwave versus Radiofrequency Ablation in Hepatocellular Carcinoma: Systematic Review and Meta-Analysis of Randomized-Controlled Trials

Introduction: Hepatocellular carcinoma (HCC) is a leading global cause of cancer-related deaths. Thermal ablation techniques, especially radiofrequency ablation (RFA) and microwave ablation (MWA), have become pivotal treatments for HCC. This systematic review and meta-analysis aim to compare these modalities, highlighting their efficacy, strengths, and limitations in treating HCC. Methods: A comprehensive literature search was conducted across major databases (PubMed, MEDLINE, Springer, ProQuest, EBSCOhost, Cochrane, and EMBASE) targeting studies on hepatocellular carcinoma with RFA and MWA. Heterogeneity analyses and pooled outcomes using random-effect models with were evaluated to compare both thermal ablation methods. Results: Nine studies, which consists of 368 patients underwent RFA and 387 patients underwent MWA, were included in review. The findings showed no significant differences in pooled analysis of volume of ablation, complete ablation rate, local tumor progression, survival rates, major complications, and adverse events. Subgroup analysis showed significantly higher risk of local tumor progression in RFA in African populations. Conclusion: No statistically significant difference was seen between outcomes across studies. MWA may offer a potential for longer therapeutic response with comparable risk of complications and adverse outcomes.

Tissue Radiologic and Pathologic Response to Biphasic Pulsed Electric Field Technology in a Porcine Model

PURPOSE

To evaluate the radiologic, pathologic, and safety characteristics of a commercially available pulsed electric field (PEF) ablation system in a porcine model.

MATERIALS AND METHODS

Monopolar biphasic PEF ablation was delivered to the liver, kidney, and longissimus dorsi muscle through a single needle via a percutaneous or open approach with the Aliya System (Galvanize Therapeutics, Redwood City, California). Six animals were ablated and evaluated in 2 cohorts (Day 3 and Day 28). Muscle, kidney, and liver were ablated in each animal. Intraprocedural cone-beam computed tomography (CT), follow-up weekly CT, blood serology, gross pathology, and histopathology were performed to characterize the radiographic evolution and tissue response.

RESULTS

There were no adverse events and no findings of electrocardiographic abnormalities, and serologic values returned to baseline by Day 28. Ablation zones were visible on unenhanced CT images during follow-up. Most identified zones became radiographically smaller over time, with some fully resolved by Day 28. The relative decrease in gross ablation zone diameter in the liver and skeletal muscle was 20% and 26%, respectively, whereas kidney sites grew in diameter by 22%. Ablation sites were focal and contained within the intended target tissue without extension to nontarget tissues or collateral structures.

CONCLUSIONS

The biphasic PEF system evaluated here resulted in a safe and predictable ablation response, with preservation of structural tissues in an animal model, offering an alternative to thermal ablative modalities, particularly near critical structures.

Microwave ablation for benign thyroid nodules with cosmetic problems and related factors for post-ablative complete relief: a two-center retrospective study

PURPOSE

To investigate the efficacy of ultrasound (US)-guided percutaneous MWA for benign thyroid nodules with cosmetic problems and identify related factors contributing to post-ablative complete relief (CR).

METHODS

This retrospective study reviewed the efficacy of MWA in treating thyroid nodules in patients with cosmetic problems who underwent MWA from January 2021 to May 2023. Patients were followed up at 1, 3, and 6 months after MWA. Pre-treatment clinical characteristics, conventional ultrasound (US) and contrast-enhanced ultrasound (CEUS) features were analyzed to explore their correlation with cosmetic improvement, defined as a cosmetic score of 1 or 2 at the 6-month follow-up. Univariable and multivariable regression analyses were carried out to identify variables associated with CR, and the related nomogram was established. Calibration curve and decision curve analysis were used to evaluate the nomogram performance.

RESULTS

118 patients with 118 nodules were included in the study. During the 1-, 3- and 6-month follow-up, the mean volume reduction ratios (VRR) were 2%, 36% and 73%, respectively. 22.0% (26/118), 57.6% (68/118), and 89.8% (106/118) patients achieved CR of cosmetic problems at 1, 3, and 6 months after MWA. In multivariable analysis, three variables (i.e., non-hashimoto's thyroiditis [HT] [OR: 90.036, P = 0.001], nodule location not close to danger triangle area [OR: 66.812, P = 0.003], early hyperenhancement on CEUS [OR: 0.035, P = 0.024]) were found to be closely associated with CR of cosmetic problems at 6 months after MWA. A nomogram model was constructed, and its accuracy was well validated (i.e., C-index = 0.914).

CONCLUSION

MWA was effective and safe for treating benign thyroid nodules with cosmetic problems. Non-HT, nodule location not close to danger triangle area, and early hyperenhancement on CEUS were associated with CR of cosmetic problems after MWA.

Safety of local thermal ablation in hepatocellular carcinoma patients with cirrhosis and severe thrombocytopenia

Generally, invasive treatment is contraindication for patients with severe thrombocytopenia, because it may increase risk of bleeding. However, many early hepatocellular carcinoma (HCC) patients with cirrhosis have platelet counts (PC) less than 50 × 109/L due to hypersplenism. These patients are often accompanied by hepatic insufficiency, which makes hepatectomy impossible, and local thermal ablation (LTA) has become a major treatment. The aim of our study is to investigate the correlation between severe thrombocytopenia and bleeding after LTA in HCC patients with cirrhosis, and evaluate risk factors of bleeding. 473 patients with cirrhosis who underwent LTA for HCC from 2016 to 2020 were enrolled, and 709 ablations were performed in total. Based on preoperative PC, cases were divided into three groups, namely, group A (PC > 50 × 109/L), group B (30 × 109/L < PC ≤ 50 × 109/L) and group C (PC ≤ 30 × 109/L). The incidence of bleeding after LTA was compared among the three groups. Logistic regression was used to explore the risk factors for bleeding after ablation. The overall incidence of bleeding complications was 4.4%, and no significant difference was observed between group A, B, and C (3.9% vs. 6.4% vs. 3.3%, P = 0.410). In multivariate analysis, tumor diameter (OR = 2.657 per 1 cm, P < 0.001), and multiple lesions (≥ 3) (OR = 3.723, P = 0.006) were found to be independent predictors of bleeding after LTA. In small HCC patients with cirrhosis and hypersplenism, the PC range 30-50 × 109/L will not increase the risk of bleeding after LTA. Tumor diameter and number of lesions are independent predictors for bleeding after LTA in HCC patients.

Immunotherapy Responses in Viral Hepatitis-Induced HCC: A Systematic Review and Meta-Analysis

Background: Hepatocellular carcinoma (HCC) is a prevalent liver cancer with poor prognosis, often linked to hepatitis B (HBV) and C (HCV) infections. This meta-analysis evaluates the efficacy of immunotherapy in HCC, particularly in cases arising from viral hepatitis. Methods: In adherence to PRISMA Statement 2020 guidelines, the immunotherapeutic outcomes comprised objective response rate (ORR), progression-free survival (PFS), and overall survival (OS). Data were analyzed from randomized controlled trials up to April 2024 using the fixed-effects models in R (V.4.3.3.) and RevMan (Cochrane). Results: This study included 9 trials with 5316 patients. The ORR was slightly higher in the viral group at 27.93% compared to 24.07% in the non-viral group, though this difference was not significant (p = 0.15). Viral HCC patients exhibited a median PFS of 7.3 months (IQR: 6.2-8.4) compared to 5.8 months (IQR: 5.48-6.13) in non-viral patients, a significant improvement (p = 0.005). Similarly, median OS was longer in the viral group at 16.8 months (IQR: 12.99-20.61) versus 15.2 months (IQR: 13.25-17.15) for non-viral HCC, which was also significant (p < 0.0001). The median OS for viral HCC was 16.8 months (IQR: 14.11-19.49 months), with HBV patients experiencing slightly higher survival at 17.15 months (IQR: 14.3-20 months) compared to 16.8 months (IQR: 12.99-20.61 months) for HCV patients; this difference was not statistically significant (p = 0.89). Conclusions: Immunotherapy shows potential in treating HCC, with significantly better outcomes in viral HCC, particularly HBV-associated cases. The heterogeneity highlights the need for personalized treatment approaches based on the viral background of HCC patients. Further research should aim to optimize these therapies to improve survival rates.

Locoregional Therapies for Hepatocellular Carcinoma in Patients with Nonalcoholic Fatty Liver Disease

Hepatocellular carcinoma (HCC) is the third most common cause of cancer-related death worldwide with an average five-year survival rate in the US of 19.6%. With the advent of HBV and HCV treatment and prevention, along with the rising rates of obesity, nonalcoholic fatty liver disease (NAFLD) and metabolic syndrome are set to overtake infectious causes as the most common cause of HCC. While surgical resection and transplantation can be curative when amenable, the disease is most commonly unresectable on presentation, and other treatment approaches are the mainstay of therapy. In these patients, locoregional therapies have evolved as a vital tool in both palliation for advanced disease and as a bridge to surgical resection and transplantation. In this review, we will be exploring the primary locoregional therapies for HCC in patients with NAFLD, including transarterial chemoembolization (TACE), bland transarterial embolization (TAE), transarterial radioembolization (TARE), and percutaneous ablation.

Analysis of technical failure after 1,613 surgical microwave ablations: A propensity score-matched analysis

BACKGROUND

Microwave ablation is becoming increasingly common for the treatment of liver tumors. Despite numerous studies aimed at identifying risk factors for local recurrence after microwave ablation, a consensus on modifiable risk factors for failure remains elusive, partly because of the limited statistical power of these studies. This study investigated the incidence of technical failure after microwave ablation, encompassing both incomplete ablation and local recurrence, and aimed to identify modifiable factors that reduce technical failure.

METHODS

This retrospective review included patients who underwent surgical microwave ablation at a high-volume institution between October 2006 and March 2023. Univariate analysis, multivariate analysis, and propensity score matching were performed to identify risk factors for technical failure.

RESULTS

A total of 1,613 surgical microwave ablations were performed on 3,035 tumors, with 226 instances (14% per procedure, 7.4% per tumor) of technical failure. Incomplete ablation occurred at a rate of 1.7% per tumor, whereas local recurrence was identified in 6.5% of ablations in per-tumor analysis. Body mass index >25 was significant for failure (odds ratio, 1.50; 95% confidence interval, 1.07-2.11; P < .05), suggesting that more difficult targeting may lead to increased technical failure rates. African American race (odds ratio, 1.62; 95% confidence interval, 1.16-2.27; P < .05), pre-microwave ablation transarterial chemoembolization (odds ratio, 1.54; 95% confidence interval, 1.08-2.21; P < .05), and previous ablation (odds ratio, 1.58; 95% confidence interval, 1.09-2.29; P < .05) were found to be statistically significant.

CONCLUSION

On the basis of the largest microwave ablation database available to date, this study identified novel modifiable and nonmodifiable risk factors of microwave ablation failure. These results can lead to decreasing technical failure rates after microwave ablation.

Non-Operating Room Anesthesia (NORA) for Ultrasound-Guided Liver Radiofrequency Ablation

INTRODUCTION

Percutaneous ultrasound-guided radiofrequency ablation (RFA) is a well-studied treatment option for locally non-advanced hepatocellular carcinoma (HCC) and colorectal liver metastases (CRLMs). Sedation is of crucial interest as it enables safe and pain-free procedures. Whether the type of sedation has an impact on procedural outcome is still not well investigated.

METHODS

We retrospectively collected data on patients undergoing liver RFA for various oncological conditions. Procedures were conducted in a non-operating room anesthesia (NORA) setting. Procedural-related complications and short-term oncological outcomes were analyzed.

RESULTS

Thirty-five patients (mean age 71.5 y, 80% male) were treated for HCC (26), CRLM (6) and gastric cancer metastases (3). Mean lesion size was 21 mm (SD ± 10.1 mm), and the most common tumor localization was the right hepatic lobe. RFA was performed in a step-up sedation approach, with subcutaneous lidocaine injection prior to needle placement and subsequent deep sedation during ablation. No anesthesia-related early or late complications occurred. One patient presented with pleural effusion due to a large ablation zone and was treated conservatively. Local tumor-free survival after 1 and 6 months was 100% in all cases where a curative RFA approach was intended.

CONCLUSIONS

NORA for liver RFA comes with high patient acceptance and tolerance, and optimal postoperative outcomes and oncologic results.

Effect of high blood flow on heat distribution and ablation zone during microwave ablation-numerical approach

Microwave ablation has become a viable alternative for cancer treatment for patients who cannot undergo surgery. During this procedure, a single-slot coaxial antenna is employed to effectively deliver microwave energy to the targeted tissue. The success of the treatment was measured by the amount of ablation zone created during the ablation procedure. The significantly large blood vessel placed near the antenna causes heat dissipation by convection around the blood vessel. The heat sink effect could result in insufficient ablation, raising the risk of local tumor recurrence. In this study, we investigated the heat loss due to large blood vessels and the relationship between blood velocity and temperature distribution. The hepatic artery, with a diameter of 4 mm and a height of 50 mm and two branches, is considered in the computational domain. The temperature profile, localized tissue contraction, and ablation zones were simulated for initial blood velocities 0.05, 0.1, and 0.16 m/s using the 3D Pennes bio-heat equation, temperature-time dependent model, and cell death model, respectively. Temperature-dependent blood velocity is modeled using the Navier-Stokes equation, and the fluid-solid interaction boundary is treated as a convective boundary. For discretization, we utilized H curl Ω elements for the wave propagation model,H 1 Ω elements for the Pennes bio-heat model, andH 1 Ω 3 × L 0 2 Ω elements for the Navier-Stokes equation, where Ω represents the computational domain. The simulated results show that blood vessels and blood velocity have a significant impact on temperature distribution, tissue contraction, and the volume of the ablation zone.

Tissue Ablation: Applications and Perspectives

Tissue ablation techniques have emerged as a critical component of modern medical practice and biomedical research, offering versatile solutions for treating various diseases and disorders. Percutaneous ablation is minimally invasive and offers numerous advantages over traditional surgery, such as shorter recovery times, reduced hospital stays, and decreased healthcare costs. Intra-procedural imaging during ablation also allows precise visualization of the treated tissue while minimizing injury to the surrounding normal tissues, reducing the risk of complications. Here, the mechanisms of tissue ablation and innovative energy delivery systems are explored, highlighting recent advancements that have reshaped the landscape of clinical practice. Current clinical challenges related to tissue ablation are also discussed, underlining unmet clinical needs for more advanced material-based approaches to improve the delivery of energy and pharmacology-based therapeutics.

Comparison of Radiofrequency Ablation and Microwave Ablation for the Management of Hepatocellular Carcinoma: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Hepatocellular carcinoma (HCC) is a common critical type of hepatic cancer worldwide. Recent guidelines have considered ablative therapeutic approaches as the primary option for managing early-stage surgically untreatable HCC. Among these therapies, radiofrequency ablation (RFA) and microwave ablation (MWA) have attained a significant role due to their efficacy and theoretical advantages. This review aims to compare and analyze the efficacy and safety of two common modalities, i.e., MWA and RFA, in the management of HCC. The literature search included PubMed, Cochrane Central Register of Controlled Trials, Medline, and Ovid for articles published until 2024. The outcomes included the local tumor progression (LTP), complete ablation (CA), the overall survival (OS) rate, or major complications. A meta-analysis was performed using Review Manager 5.3. The systematic review included six randomized controlled trials, including 826 patients. The findings revealed that MWA resulted in lower LTP and higher CA rates compared to RFA. However, the effect of complications was higher in the MWA therapy group. Despite that, the differences between all parameters were not significant. Statistical significance was not evident in the OS rates between the two modalities. Three studies found comparable survival rates between the two modalities, while one study reported similar local tumor recurrence-free survival rates between the two approaches. Both techniques appear to be effective and safe for the management of liver tumors, providing clinicians with valuable options for personalized patient care. Further high-quality research is needed to confirm these findings and guide clinical decision-making.

Comparative efficacy and safety of radiofrequency ablation and microwave ablation in benign thyroid nodule treatment: a systematic review and meta-analysis

OBJECTIVE

Ultrasound-guided thermal ablation, including radiofrequency ablation (RFA) and microwave ablation (MWA), has become one of the main options for treating benign thyroid nodules (BTNs). To assess the efficacy of thermal ablation of BTNs, we performed a systematic review and meta-analysis of relevant studies.

MATERIALS AND METHODS

A comprehensive search of MEDLINE, EMBASE, and COCHRANE databases was performed up to September 25, 2023, to identify studies directly comparing RFA and MWA for pathologically proven BTNs and reporting clinical outcomes and complications. Data extraction and quality assessment were independently performed by two radiologists according to PRISMA guidelines. The analysis yielded the serial volume reduction ratios (VRRs) of ablated nodules for up to 12 months, symptom and cosmetic scores, and complications.

RESULTS

This analysis included nine studies with 1305 BTNs treated by RFA and 1276 by MWA. VRRs at 1 month, 3 months, and 6 months were similar between RFA and MWA, but RFA showed a significantly higher VRR (83.3%) than MWA (76.9%) at 12 months (p = 0.02). Complication rates showed no significant difference between the two methods. Symptom and cosmetic scores significantly decreased after ablation, without a significant difference between the methods. Subgroup analysis indicated a significantly higher VRR at 12 months for RFA than for MWA for less experienced investigators (≤ 10 years), but no significant difference for more experienced investigators (> 10 years).

CONCLUSION

RFA and MWA are both effective and safe methods for treating BTNs. RFA showed a higher VRR at 12 months and seems more suitable for less experienced investigators.

CLINICAL RELEVANCE STATEMENT

RFA and MWA are both effective and safe treatments for BTNs, with RFA showing a higher VRR at 12 months. Both methods offer minimally invasive and reliable treatment for thyroid nodules.

KEY POINTS

The most effective thermal ablation technique for BTNs remains undetermined. RFA showed a higher VRR at 12 months than MWA. Both techniques are effective for treating thyroid nodules; RFA offers greater benefits, particularly for less experienced investigators.

Meta-analysis of transarterial chemoembolization combined with cryoablation vs transarterial chemoembolization alone for ≥ 5 cm hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) ranks sixth globally in cancer incidence and third in mortality rates. Unfortunately, over 70% of HCC patients forego the opportunity for curative surgery or liver transplantation due to inadequate physical examinations, poor physical condition, and limited organ availability upon diagnosis. Clinical guidelines endorse transarterial chemoembolization (TACE) as the frontline treatment for intermediate to advanced-stage HCC. Cryoablation (CRA) is an emerging local ablative therapy increasingly used in HCC management. Recent studies suggest that combining CRA with TACE offers complementary and synergistic effects, potentially improving long-term survival rates. However, the superiority of combined TACE + CRA therapy over TACE alone for HCC lesions equal to or exceeding 5 cm requires further investigation.

AIM

To compare the efficacy and safety of TACE combined with CRA vs TACE alone in the treatment of HCC with a diameter of ≥ 5 cm.

METHODS

PubMed, EMBASE, Cochrane Library, CNKI, Wanfang, and VIP databases were searched to retrieve all relevant studies on TACE and CRA up to July 2022. Meta-analysis was performed using RevMan 5.3 software.

RESULTS

After screening according to the inclusion and exclusion criteria, 6 articles were included, including 2 randomized controlled trials and 4 nonrandomized controlled trials, with a total of 575 patients included in the meta-analysis. The results showed that the objective response rate [odds ratio (OR) = 2.56, 95% confidence interval (CI):1.66-3.96, P < 0.0001), disease control rate (OR = 3.03, 95%CI: 1.88-4.89, P < 0.00001), 1-year survival rate (OR = 3.79, 95%CI: 2.50-5.76, P < 0.00001), 2-year survival rate (OR = 2.34, 95%CI: 1.43-3.85, P = 0.0008), and 3-year survival rate (OR = 3.34, 95%CI: 1.61-6.94, P = 0.001) were all superior to those of the control group; the postoperative decrease in alpha-fetoprotein value (OR = 295.53, 95%CI: 250.22-340.85, P < 0.0001), the postoperative increase in CD4 value (OR = 10.59, 95%CI: 8.78-12.40, P < 0.00001), and the postoperative decrease in CD8 value (OR = 6.47, 95%CI: 4.44-8.50, P < 0.00001) were also significantly higher than those in the TACE-alone treatment group.

CONCLUSION

Compared with TACE-alone treatment, TACE + CRA combined treatment not only improves the immune function of HCC patients with a diameter of ≥ 5 cm, but also enhances the therapeutic efficacy and long-term survival rate, without increasing the risk of complications. Therefore, TACE + CRA combined treatment may be a more recommended treatment for patients with HCC with a diameter of ≥ 5 cm.

Adjuvant holmium-166 radioembolization after radiofrequency ablation in early-stage hepatocellular carcinoma patients: a dose-finding study (HORA EST HCC trial)

PURPOSE

The aim of this study was to investigate the biodistribution of (super-)selective trans-arterial radioembolization (TARE) with holmium-166 microspheres (166Ho-MS), when administered as adjuvant therapy after RFA of HCC 2-5 cm. The objective was to establish a treatment volume absorbed dose that results in an absorbed dose of ≥ 120 Gy on the hyperemic zone around the ablation necrosis (i.e., target volume).

METHODS

In this multicenter, prospective dose-escalation study in BCLC early stage HCC patients with lesions 2-5 cm, RFA was followed by (super-)selective infusion of 166Ho-MS on day 5-10 after RFA. Dose distribution within the treatment volume was based on SPECT-CT. Cohorts of up to 10 patients were treated with an incremental dose (60 Gy, 90 Gy, 120 Gy) of 166Ho-MS to the treatment volume. The primary endpoint was to obtain a target volume dose of ≥ 120 Gy in 9/10 patients within a cohort.

RESULTS

Twelve patients were treated (male 10; median age, 66.5 years (IQR, [64.3-71.7])) with a median tumor diameter of 2.7 cm (IQR, [2.1-4.0]). At a treatment volume absorbed dose of 90 Gy, the primary endpoint was met with a median absorbed target volume dose of 138 Gy (IQR, [127-145]). No local recurrences were found within 1-year follow-up.

CONCLUSION

Adjuvant (super-)selective infusion of 166Ho-MS after RFA for the treatment of HCC can be administered safely at a dose of 90 Gy to the treatment volume while reaching a dose of ≥ 120 Gy to the target volume and may be a favorable adjuvant therapy for HCC lesions 2-5 cm.

TRIAL REGISTRATION

Clinicaltrials.gov NCT03437382 . (registered: 19-02-2018).

Long-term results of liver thermal ablation in patients with hepatocellular carcinoma and colorectal cancer liver metastasis regarding spatial features and tumor-specific variables

PURPOSE

Colorectal cancer liver metastasis (CRLM) and hepatocellular carcinoma (HCC) are widely treated using microwave and radiofrequency ablation. Local tumor progression (LTP) may develop depending on the shortest vascular distance and large lesion diameter. This study aims to explore the effect of these spatial features and to investigate the correlation between tumor-specific variables and LTP.

METHODS

This is a retrospective study covering the period between January 2007 and January 2019. One hundred twenty-five patients (CRLM: HCC: 64:61) with 262 lesions (CRLM: HCC: 142:120) were enrolled. The correlation between LTP and the variables was analyzed using the chi-square test, Fischer's exact test, or the Fisher-Freeman-Halton test where applicable. The local progression-free survival (Loc-PFS) was analyzed using the Kaplan-Meier method. Univariable and multivariable Cox regression analyses were performed to identify prognostic factors.

RESULTS

Significant correlations were observed for LTP in both CRLM and HCC at a lesion diameter of 30-50 mm (P = 0.019 and P < 0.001, respectively) and SVD of ≤3 mm (P < 0.001 for both). No correlation was found between the ablation type and LTP (CRLM: P = 0.141; HCC: P = 0.771). There was no relationship between residue and the ablation type, but a strong correlation with tumor size was observed (P = 0.127 and P < 0.001, respectively). In CRLM, LTP was associated with mutant K-ras and concomitant lung metastasis (P < 0.001 and P = 0.003, respectively). In HCC, a similar correlation was found for Child-Pugh B, serum alpha-fetoprotein (AFP) level of >10 ng/mL, predisposing factors, and moderate histopathological differentiation (P < 0.001, P = 0.008, P = 0.027, and P < 0.001, respectively). In CRLM, SVD of ≤3 mm proved to be the variable with the greatest negative effect on Loc-PFS (P = 0.007), followed by concomitant lung metastasis (P = 0.027). In HCC, a serum AFP level of >10 ng/mL proved to be the variable with the greatest negative effect on Loc-PFS (P = 0.045).

CONCLUSION

In addition to the lesions' spatial features, tumor-specific variables may also have an impact on LTP.