Local recurrence of hepatocellular carcinoma in the tumor blood drainage area following radiofrequency ablation

Comparison of local recurrence in transcatheter arterial chemoembolization of hepatocellular carcinoma with or without accumulation of iodized oil beyond corona enhancement area: Short-term results

Background

Local tumor recurrence of hepatocellular carcinoma (HCC) often occurs in blood drainage areas. Corona enhancement is determined by computed tomography during hepatic arteriography (CTHA) and is considered to represent the blood drainage area. This study aimed to investigate the relationship between embolization of corona enhancement area and local tumor recurrence of patients with HCC who underwent transcatheter arterial chemoembolization (TACE).

Patients and methods

The study retrospectively selected 53 patients with 60 HCC nodules that showed corona enhancement area on late-phase CTHA and showed homogenous accumulation of iodized oil throughout the nodule on non-contrast-enhanced CT performed immediately after TACE. We divided the nodules into two groups, according to whether the accumulation of iodized oil covered the entire corona enhancement area (group A) or not (group B). Local tumor recurrence was compared between the two groups.

Results

The cumulative local tumor recurrence rates for group A (n = 36) were 2.8%, 2.8%, 8.3% at 3, 6, and 12 months, respectively, whereas the recurrence rates for group B (n = 24) were 20.8%, 45.8%, 75% at 3, 6, and 12 months, respectively. The cumulative local tumor recurrence rates for group A were significantly lower than those for group B (hazard ratio, 0.079; 95% confidence interval, 0.026–0.24; p < 0.001).

Conclusions

The results of the study suggest that the corona enhancement area may be an accurate safety margin in TACE which should be performed until the embolic area covers the entire corona enhancement area.

An Optimal Ablative Margin of Small Single Hepatocellular Carcinoma Treated with Image-Guided Percutaneous Thermal Ablation and Local Recurrence Prediction Base on the Ablative Margin: A Multicenter Study

Objective

To explore the best ablative margin (AM) for single hepatocellular carcinoma (HCC) patients with image-guided percutaneous thermal ablation (IPTA) based on MRI–MRI fusion imaging, and to develop and validate a local tumor progression (LTP) predictive model based on the recommended AM.

Methods

Between March 2014 and August 2019, 444 treatment-naïve patients with single HCC (diameter ≤3 cm) who underwent IPTA as first-line treatment from three hospitals were included, which were randomly divided into training (n= 296) and validation (n = 148) cohorts. We measured the ablative margin (AM) by MRI–MRI fusion imaging based on pre-ablation and post-ablation images. Then, we followed up their LPT and verified the optimal AM. Risk factors related to LTP were explored through Cox regression models, the nomogram was developed to predict the LTP risk base on the risk factors, and subsequently validated. The predictive performance and discrimination were assessed and compared with conventional indices.

Results

The median follow-up was 19.9 months (95% CI 18.0–21.8) for the entire cohort. The results revealed that the tumor size (HR: 2.16; 95% CI 1.25–3.72; P = 0.003) and AM (HR: 0.72; 95% CI, 0.61–0.85; P < 0.001) were independent prognostic factors for LTP. The AM had a pronounced nonlinear impact on LTP, and a cut-off value of 5-mm was optimal. We developed and validated an LTP predictive model based on the linear tumor size and nonlinear AM. The model showed good predictive accuracy and discrimination (training set, concordance index [C-index] of 0.751; validation set, C-index of 0.756) and outperformed other conventional indices.

Conclusion

The 5-mm AM is recommended for the best IPTA candidates with single HCC (diameter ≤3 cm). We provided an LTP predictive model that exhibited adequate performance for individualized prediction and risk stratification.

Radiofrequency Ablation Covering the Entire Tumor Blood Drainage Area Improves Survival in Hepatocellular Carcinoma

Hepatocellular carcinoma has been considered to disseminate through the tumor blood drainage area. To improve curation rates, treatment should cover this area as it may contain satellite lesions. This retrospective study aimed to investigate whether radiofrequency ablation (RFA) completely covering the blood drainage area can improve the overall and disease-free survival. We enrolled 526 patients who underwent computed tomography during hepatic arteriography following RFA from April 2001 to May 2019. Patients were categorized into a covered group in which the blood drainage area was completely covered by RFA and a noncovered group in which coverage was incomplete. The primary endpoint was the overall survival rate; secondary outcomes included disease-free survival rate, distant intrahepatic and local recurrence rate, and changes in the Child-Pugh score. There were no significant differences in baseline characteristics between the two groups. Cumulative overall survival rates were significantly higher in the covered group than in the noncovered group (hazard ratio, 0.63; 95% confidence interval, 0.48-0.84; P = 0.002). On multivariate Cox proportional hazard model analysis, age <65 years, Child-Pugh class A, and coverage of the entire drainage area were independent protective factors. Child-Pugh worsened in 11 (4.2%) patients in the covered group compared to 18 (6.7%) patients in the noncovered group. Conclusion: RFA covering the complete drainage area improved overall survival without decreasing liver function.

Intraprocedurally EOB-MRI/US fusion imaging focusing on hepatobiliary phase findings can help to reduce the recurrence of hepatocellular carcinoma after radiofrequency ablation

BACKGROUND & AIMS

To explore the ability of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid magnetic resonance imaging (EOB-MRI)/ultrasound (US) fusion imaging (FI) to improve the prognosis of radiofrequency ablation (RFA) by ablating the characteristic findings of hepatocellular carcinoma (HCC) in hepatobiliary phase (HBP) imaging.

METHODS

We retrospectively recruited 115 solitary HCC lesions with size of (15.9 ± 4.6) mm. They were all treated by RFA and preoperative EOB-MRI. According to the modalities guiding RFA performance, the lesions were grouped into contrast enhanced US (CEUS)/US guidance group and EOB-MRI/US FI guidance group. For the latter group, the ablation scope was set to cover the HBP findings (peritumoral hypointensity and irregular protruding margin). The presence of HBP findings, the modalities guided RFA, the recurrence rate were observed.

RESULTS

After an average follow-up of 377 days, local tumor progression (LTP) and intrahepatic distant recurrence (IDR) were 14.8% and 38.4%, respectively. The lesions having HBP findings exhibited a higher recurrence rate (73.7%) than the lesions without HBP findings (42.9%) (p = 0.002) and a low overall recurrence-free curve using the Kaplan-Meier method (p = 0.038). Using EOB-MRI/US FI as guidance, there was no difference in the recurrence rate between the groups with and without HBP findings (p = 0.799). In lesions with HBP findings, RFA guided by EOB-MRI/US FI (53.8%) produced a lower recurrence rate than CEUS/US (84.0%) (p = 0.045).

CONCLUSIONS

The intraprocedurally application of EOB-MRI/US FI to determine ablation scope according to HBP findings is feasible and beneficial for prognosis of RFA.

Combined Ultrasound and CT-Guided Iodine-125 Seeds Implantation for Treatment of Residual Hepatocellular Carcinoma Located at Complex Sites After Transcatheter Arterial Chemoembolization

Purpose

The purpose of this study was to evaluate the efficacy and safety of iodine-125 (¹²⁵I) seeds implantation under ultrasound and computed tomography (CT) guidance in the treatment of residual hepatocellular carcinoma (HCC) located at complex sites after transcatheter arterial chemoembolization (TACE).

Methods

This retrospective study analyzed the consecutive medical records of 31 HCC patients with residual tumors located at complex sites (such as large blood vessels, gallbladder, diaphragm dome, etc.) after TACE from May 2014 to December 2018, all of whom received ¹²⁵I seeds implantation therapy. Overall survival (OS), progression-free survival (PFS), recurrence, and complications were documented.

Results

A total of 607 seeds were implanted in 31 patients, with an average of 19.6±10.4 (range, 8–48) seeds per patient. Median OS and PFS were 33 months (95% CI: 27.1 months, 38.9 months) and 15 months (95% CI: 9.6 months, 20.4 months), respectively. Although univariate analysis showed that albumin, prothrombin time, alpha-fetoprotein level, Child-Pugh score, and lipiodol deposition in tumor were associated with OS, multivariate analysis showed that none of them was an independent prognostic factor for OS. Multivariate analysis showed that prothrombin time was an independent prognostic factor for PFS. No operation-related deaths in this study. Although pneumothorax was present in two patients and subcutaneous abscess in one patient, symptoms improved in all three patients with appropriate treatment. Common minor complications included fever, abdominal pain and leukopenia and no grade≥3 adverse events were observed.

Conclusions

¹²⁵I seeds implantation under the combined guidance of ultrasound and CT is safe and effective for patients with residual HCC located at complex sites after TACE. This is a promising treatment approach and deserves further discussion.

Assessment of Ablative Margin After Microwave Ablation for Hepatocellular Carcinoma Using Deep Learning-Based Deformable Image Registration

Aim: To assess the ablative margin (AM) after microwave ablation (MWA) for hepatocellular carcinoma (HCC) with a deep learning-based deformable image registration (DIR) technique and analyze the relation between the AM and local tumor progression (LTP).

Patients and Methods: From November 2012 to April 2019, 141 consecutive patients with single HCC (diameter ≤ 5 cm) who underwent MWA were reviewed. Baseline characteristics were collected to identify the risk factors for the determination of LTP after MWA. Contrast-enhanced magnetic resonance imaging scans were performed within 1 month before and 3 months after treatment. Complete ablation was confirmed for all lesions. The AM was measured based on the margin size between the tumor region and the deformed ablative region. To correct the misalignment, DIR between images before and after ablation was achieved by an unsupervised landmark-constrained convolutional neural network. The patients were classified into two groups according to their AMs: group A (AM ≤ 5 mm) and group B (AM > 5 mm). The cumulative LTP rates were compared between the two groups using Kaplan–Meier curves and the log-rank test. Multivariate analyses were performed on clinicopathological variables to identify factors affecting LTP.

Results: After a median follow-up period of 28.9 months, LTP was found in 19 patients. The mean tumor and ablation zone sizes were 2.3 ± 0.9 cm and 3.8 ± 1.2 cm, respectively. The mean minimum ablation margin was 3.4 ± 0.7 mm (range, 0–16 mm). The DIR technique had higher AUC for 2-year LTP without a significant difference compared with the registration assessment without DL (P = 0.325). The 6-, 12-, and 24-month LTP rates were 9.9, 20.6, and 24.8%, respectively, in group A, and 4.0, 8.4, and 8.4%, respectively, in group B. There were significant differences between the two groups (P = 0.011). Multivariate analysis showed that being >65 years of age (P = 0.032, hazard ratio (HR): 2.463, 95% confidence interval (CI), 1.028–6.152) and AM ≤ 5 mm (P = 0.010, HR: 3.195, 95% CI, 1.324–7.752) were independent risk factors for LTP after MWA.

Conclusion: The novel technology of unsupervised landmark-constrained convolutional neural network-based DIR is feasible and useful in evaluating the ablative effect of MWA for HCC.

Iodine-125 Brachytherapy Can Prolong Progression-Free Survival of Patients with Locoregional Recurrence and/or Residual Hepatocellular Carcinoma After Radiofrequency Ablation

Background: Radiofrequency ablation (RFA) for the treatment of hepatocellular carcinoma (HCC) is limited by locoregional recurrence and/or residual tumors caused by incomplete ablation. Iodine-125 brachytherapy can achieve a high local control rate in solid carcinoma, but few studies have assessed the efficacy of this treatment for locoregional recurrence and/or residual HCC after RFA. Objective: To investigate the effectiveness and safety of iodine-125 brachytherapy for treating locoregional recurrence and/or residual HCC in patients treated with RFA. Methods: Eligible study patients were those with locoregional recurrence and/or residual HCC on abdominal imaging performed 1 month after RFA at this institution between February 2009 and September 2014 retrospectively. Patients were divided into either the control group (no treatment until the tumor progressed) or the treatment group (underwent iodine-125 brachytherapy). Progression-free survival (PFS), overall survival (OS), and complications of iodine-125 brachytherapy were evaluated. Results: A total of 42 patients were included in the final analysis, including 29 in the control group and 13 in the treatment group. A total of 457 iodine-125 particles were used (mean 32.8 ± 21.3 mCi per case). The median follow-up time was 25 months. Median PFS was 9 months in the control group and 18 months in the treatment group (p = 0.026). The median OS was 28 months in the control group and 33 months in the treatment group (p = 0.441). There were no major complications observed in patients treated with iodine-125 brachytherapy. Conclusion: Iodine-125 brachytherapy can prolong PFS in patients with locoregional recurrence and/or residual HCC after RFA.

"Logic-Based Medicine" Is More Feasible than "Evidence-Based Medicine" in the Local Treatment for Hepatocellular Carcinoma

The optimal type of surgery (e.g., anatomic or non-anatomic resection) or radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC) is still under debate despite numerous comparative studies based on overall survival. This debate continues not only because these endpoints are influenced by non-surgical factors, such as liver function, but because the definition of non-anatomic resection for HCC has remained unclear. The optimal surgery could be logically determined based on the mechanism of local intrahepatic metastasis, that is, the drainage of tumour blood flow (TBF), because HCC spreads locally through tumour blood flowing to the peri-tumourous liver parenchyma. Since TBF is clearly demonstrated by CT scan under hepatic arteriography, the surgical margin can be determined individually based on the drainage of TBF without deteriorating local curability. Controversy regarding RFA and surgery does not result from the curability of treatment itself but from the lack of scientific evidence on safety margins. Based on proper concepts and self-evident truths, an algorithm of loco-regional treatment for HCC is proposed.

Prospective cohort trial to confirm the efficacy of no-touch radio frequency ablation

BACKGROUND AND AIM

The aim of the present prospective study was to evaluate tumor recurrence (intrasubsegmental recurrence-free survival and local tumor recurrence-free survival) and hepatic functional reserve following no-touch ablation.

METHODS

The prospective cohort study protocols were approved by the institutional ethics committee. All patients provided written, informed consent. Between January 2014 and September 2016, 231 patients with 277 hepatocellular carcinoma nodules were prospectively enrolled. An internally cooled bipolar electrode was used for no-touch ablation, while a monopolar electrode was used for direct puncture ablation. The intrasubsegmental recurrence-free survival rate was the primary end-point. The secondary outcomes were the local recurrence-free survival rate, the disease-free survival rate, and the changes in the Child-Pugh score.

RESULTS

No-touch ablation resulted in significantly higher cumulative intrasubsegmental tumor recurrence-free survival rates than direct puncture ablation (98.0% vs 87.1% at 1 year, 96.9% vs 76.8% at 2 years, and 91.0% vs 68.3% at 3 years, P < 0.001). The no-touch group also showed significantly better local recurrence-free survival and disease-free survival. Even when only primary cases were analyzed, the same results were obtained. To adjust for differences in the background characteristics, inverse probability of treatment weighting adjustment was performed. Only intrasubsegmental tumor recurrence-free survival was significantly better in the no-touch group (hazard ratio [HR], 0.08; 95% confidence interval [CI], 0.02-0.20, P < 0.001); there was no difference in local tumor recurrence-free survival (HR, 0.36; 95% CI, 0.10-1.02, P = 0.071).

CONCLUSIONS

No-touch ablation appears to be an ideal method for the prevention of intrahepatic dissemination.

Iodine-125 Brachytherapy Prophylaxis after Radiofrequency Ablation Cannot Benefit Patients in High Risk of Locoregional Hepatocellular Carcinoma Recurrence

This study evaluated if iodine-125 brachytherapy prophylaxis after radiofrequency ablation (RFA) prolongs time to recurrence (TTR) and overall survival (OS) of patients in high risk of locoregional hepatocellular carcinoma (HCC) recurrence. 116 patients with total tumor necrosis after RFA were divided into iodine-125 brachytherapy prophylaxis treatment group and control group. The primary endpoint was TTR, and secondary endpoints were OS and treatment-related adverse events. There were no significant differences among the baseline characteristics of two subgroups patients. The mean iodine-125 particles were 29.8 (26.59 ± 12.51 mCi) per patient. The mean follow-up was 25 months, and mean TTR of treatment and control groups were 21.7 and 15.9 months (P = 0.733); mean OS of two subgroups were 41.7 and 40.9 months (P = 0.316). There were no significant differences of 1-, 2-, 3-, 4-and 5-years TTR and OS and patients’ immunity pre- and 1 month post-treatment. Extrahepatic metastasis was found to have a statistically significant influence on TTR, and AFP, extrahepatic metastasis were found to have a statistically significant influence on OS by multivariate analysis. There was no major complications and procedure related death. Iodine-125 brachytherapy prophylaxis after RFA can’t improve TTR and OS of HCC patients who were in high risk of locoregional tumor recurrence.

Effect of treatment support on preventing local recurrence of hepatocellular carcinoma directly adjacent to the diaphragm

Treatment support is anticipated to improve the results of radiofrequency ablation (RFA) treatment in cases in which visualization of tumors using the conventional B-mode is unclear. In the present study, the effectiveness of treatment support for RFA reducing the local recurrence rate of hepatocellular carcinoma (HCC) that are located directly adjacent to the diaphragm, and which are difficult to visualize with B-mode ultrasound imaging, was investigated. A total of 103 HCC tumors measuring <5 cm, which were located abutting the diaphragm, and which were difficult to visualize using the B-mode, were treated using RFA. Thirty-three of those HCC tumors were treated using RFA without treatment support, whereas the remaining 70 HCC tumors were treated using RFA with treatment support, including artificial pleural effusion, contrast-enhanced ultrasonography (CEUS) with the contrasting agent, Sonazoid™, and fusion imaging, either alone or in combination to improve the visualization of the tumors. The rate of local recurrence, and factors affecting local recurrence, were analyzed. Local recurrences were confirmed in 17 of the 103 nodules (16.50%). The overall rate of local recurrence was 13.1% at 6 months, and 20.2% at 12 months. The rate of local recurrence using RFA with artificial pleural effusion was significantly lower compared with those cases of HCC tumors treated without artificial pleural effusion (P=0.008). Similarly, the rate of local recurrence for CEUS RFA with Sonazoid™ was significantly lower compared with those cases of HCC tumors treated without Sonazoid™ (P=0.00081). In a multivariate analysis, CEUS RFA with Sonazoid™ and artificial pleural effusion contributed to the decrease in the rate of local recurrence (hazard ratios, 0.075 and 0.143, respectively). Based on these results, it is possible to conclude that CEUS with Sonazoid™ as a treatment support was the most effective method for reducing the rate of local recurrences abutting the diaphragm that are difficult to visualize using B-mode ultrasonography.

Short-Term Results of Laparoscopic Radiofrequency Ablation Using a Multipolar System for Localized Hepatocellular Carcinoma

BACKGROUND AND AIM

Multipolar radiofrequency ablation (RFA) is feasible for the treatment of hepatocellular carcinoma (HCC) for which a large ablative area is planned, and it imposes a light physical burden on patients. Multipolar RFA via the percutaneous approach is performed in the majority of cases, but the efficacy of multipolar RFA with a laparoscopic approach has rarely been studied. This study aimed to evaluate the efficacy and safety of multipolar laparoscopic RFA (LRA) for localized HCC over the short term.

METHODS

From January 2014 to January 2016, 77 consecutive patients with 130 HCCs treated by multipolar LRA were assessed. One to three bipolar needle applicators were inserted under laparoscopic ultrasonography guidance, regardless of tumor location. We intended to achieve parallel insertions and no-touch ablation as much as possible.

RESULTS

The median size of the main tumor was 22 mm (range, 10-42 mm). The median follow-up time was 13.6 months (range, 3.1-24.8 months). In all cases, a sufficient ablative area was obtained as planned, without thermal injury of adjacent organs. During the follow-up period, all patients were alive with no local tumor progression, while intrahepatic recurrence distant from the primary site occurred in 7 patients. The 2-year local tumor progression-free survival rate and overall cancer-free survival rate were 100 and 81.6%, respectively. There were no procedural major complications caused prolonging the hospitalization, and all patients were discharged without subjective symptoms 4-7 days after LRA.

CONCLUSIONS

Multipolar LRA was efficacious in the treatment of localized HCCs by safely achieving a good ablative area.

Evaluation of the ablation margin of hepatocellular carcinoma using CEUS-CT/MR image fusion in a phantom model and in patients

Background

To assess the accuracy of contrast-enhanced ultrasound (CEUS)-CT/MR image fusion in evaluating the radiofrequency ablative margin (AM) of hepatocellular carcinoma (HCC) based on a custom-made phantom model and in HCC patients.

Methods

Twenty-four phantoms were randomly divided into a complete ablation group (n = 6) and an incomplete ablation group (n = 18). After radiofrequency ablation (RFA), the AM was evaluated using ultrasound (US)-CT image fusion, and the results were compared with the AM results that were directly measured in a gross specimen. CEUS-CT/MR image fusion and CT-CT / MR-MR image fusion were used to evaluate the AM in 37 tumors from 33 HCC patients who underwent RFA.

Results

The sensitivity, specificity, and accuracy of US-CT image fusion for evaluating AM in the phantom model were 93.8, 85.7 and 91.3%, respectively. The maximal thicknesses of the residual AM were 3.5 ± 2.0 mm and 3.2 ± 2.0 mm in the US-CT image fusion and gross specimen, respectively. No significant difference was observed between the US-CT image fusion and direct measurements of the AM of HCC. In the clinical study, the success rate of the AM evaluation was 100% for both CEUS-CT/MR and CT-CT/MR-MR, and the duration was 8.5 ± 2.8 min (range: 4–12 min) and 13.5 ± 4.5 min (range: 8–16 min) for CEUS-CT/MR and CT-CT/MR-MR, respectively. The sensitivity, specificity, and accuracy of CEUS-CT/MR imaging for evaluating the AM were 100.0, 80.0, and 90.0%, respectively.

Conclusions

A phantom model composed of carrageenan gel and additives was suitable for the evaluation of HCC AM. CEUS-CT/MR image fusion can be used to evaluate HCC AM with high accuracy.