Risk factors for local recurrence of small hepatocellular carcinoma tumors after a single session, single application of percutaneous radiofrequency ablation

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.

Improved clinical outcome using transarterial chemoembolization combined with radiofrequency ablation for patients in Barcelona clinic liver cancer stage A or B hepatocellular carcinoma regardless of tumor size: results of a single-center retrospective case control study

Background

To determine the safety and efficacy of transarterial chemoembolization (TACE) combined with radiofrequency ablation (hereafter, TACE-RFA) in treating Barcelona Clinic Liver Cancer (BCLC) Stage A or B (hereafter, BCLC A/B) hepatocellular carcinoma (HCC) patients, and to explore the range of tumor sizes suitable for combination therapy.

Methods

This retrospective study assessed the consecutive medical records of HCC patients with BCLC A/B who received TACE-RFA or TACE from September 2009 to September 2018. Progression-free survival (PFS), overall survival (OS), therapeutic response, and complications were compared between the two groups.

Results

Among 2447 patients who received TACE-RFA or TACE, 399 eligible patients were enrolled in our study, including 128 patients in the TACE-RFA group and 271 patients in the TACE group. Compared with the TACE group, the PFS and OS rates of 1,3,5,8 years in the TACE-RFA group were significantly better, with higher objective tumor regression rate and better disease control rate. RFA treatment did not increase the risk of death in patients with HCC, and both liver subcapsular hematoma and bile duct injury were improved by symptomatic treatment. Serum α-fetoprotein level and treatment method were important independent prognostic factors for OS, whereas albumin, hepatitis B and treatment method were important independent prognostic factors for PFS. Subgroup analysis showed that patients in the TACE-RFA group always showed better OS and PFS.

Conclusions

TACE-RFA had an advantage over TACE alone in prolonging PFS and improving OS in HCC patients with BCLC A/B, and can benefit patients regardless of tumor size.

Chemoembolization Combined with Radiofrequency Ablation for Medium-Sized Hepatocellular Carcinoma: A Propensity-Score Analysis

PURPOSE

To compare survival outcomes of patients with single medium-sized hepatocellular carcinomas (HCCs) who underwent treatment with transarterial chemoembolization, radiofrequency (RF) ablation, or a combination of the 2 therapies.

MATERIALS AND METHODS

Between 2000 and 2016, 538 patients underwent combined chemoembolization and RF ablation (n = 109), chemoembolization alone (n = 314), or RF ablation alone (n = 115) as first-line treatment for a single medium-sized (3.1-5.0 cm) HCC. Baseline demographic data (age, sex, etiology, Eastern Cooperative Oncology Group performance status, presence of liver cirrhosis, and serum bilirubin, albumin, and α-fetoprotein levels) were similar among groups except for Child-Pugh class, albumin level, and tumor size. Propensity-score analysis with inverse probability weighting (IPW) was used to reduce any bias in treatment selection and other potential confounding factors.

RESULTS

Median follow-up time was 46.2 months. Before IPW, overall survival (OS) durations were significantly different among the 3 groups (median, 85 months for combined therapy, 56.5 months for chemoembolization alone, and 52.1 months for RF ablation alone; P = .01). The 10-year OS rates were 40.1%, 25.5%, and 19.5% for the combined, chemoembolization-only, and RF ablation-only groups, respectively. After IPW, OS remained superior in the combined chemoembolization/RF ablation group compared with the monotherapy groups (10-y OS, 41.8% with combined therapy, 28.4% with chemoembolization alone, and 11.9% with RF ablation alone; P = .022).

CONCLUSIONS

Chemoembolization plus RF ablation may provide better survival outcomes than chemoembolization or RF ablation monotherapy, and can be considered a viable alternative treatment for unresectable single medium-sized HCCs.

Janus Microcarriers for Magnetic Field-controlled Combination Chemotherapy of Hepatocellular Carcinoma†

Combination chemotherapy administering multiple chemo-agents is widely exploited for the treatment of various cancers in the clinic. Specially for hepatocellular carcinoma (HCC), one of the most common malignancies, a co-administration of combinational cytostatic multi-kinase inhibitors and cytotoxic chemo-agents has been suggested as a potential curative approach. Here, Janus microcarriers were developed for the controlled local combination chemotherapy of HCC. The Janus microcarriers are composed of polycaprolactone (PCL) compartment and magnetic nanoparticles-loaded poly(lactide-co-glycolic acid) (PLGA) compartment which contain hydrophobic regorafenib and hydrophilic doxorubicin, respectively. Exploiting the magnetic anisotropy, rotational motion of the Janus microcarriers is controlled with magnetic field, which enables the active co-release of dual chemo-agents. Furthermore, Janus microcarriers exhibit magnetic resonance (MR) contrast effect, supporting the successful transcatheter intra-arterial delivery of the combination chemo-agents loaded the microcarriers to the targeted tumor. This Janus microcarriers potentially serve as a general combinational chemo-therapeutic platform for the co-delivery of various combinations of multi-chemo-agents.

Ultrasonic Cavitation Ameliorates Antitumor Efficacy of Residual Cancer After Incomplete Radiofrequency Ablation in Rabbit VX2 Liver Tumor Model

Residual cancer after incomplete ablation remains a major problem for radiofrequency ablation (RFA). We aimed to investigate the synergetic treatment efficacy of RFA combined with ultrasonic cavitation for liver tumor. Sixty rabbits with VX2 liver tumor were randomly divided into three groups. Group A was control group without any treatment. Combined ultrasonic cavitation with RFA was performed for group B1. Group B2 underwent RFA alone. The histopathological results were compared at the 5th, 11th, and 18th day of experiment, and the survival time and metastasis were assessed. The tumor volume growth rate, percentage of necrosis area, microvessel density, and apoptosis index showed significant differences among these groups at the 5th day, 11th day, and 18th day of experiment (P < .05). In contrast, the difference of metastatic score was not significant at the 5th and 11th day (P > .05). At the 18th day, the metastatic score of group A was significant higher than that of group B1 (P < .05), whereas the differences between group A and group B2, or group B1 and group B2 were not significant (P > .05). The median/range interquartile of survival time in groups A, B1, and B2 were 25/8 days, 50/19 days, and 48/20 days, respectively, and there was significant difference between groups A and B1 or B2 (P < .05). The difference between groups B1 and B2 was not significant (P > .05). Ultrasonic cavitation after incomplete RFA for liver tumor improved the antitumor effect, which could be considered as a potentially useful combined therapeutic strategy for liver malignancy.

Radiotherapy for Hepatocellular Carcinoma Results in Comparable Survival to Radiofrequency Ablation: A Propensity Score Analysis

Potentially curative treatments for early-stage hepatocellular carcinoma (HCC) have drawbacks and contraindications. Recently, radiotherapy has achieved good outcomes. We compared the outcomes of radiotherapy and radiofrequency ablation (RFA) for early-stage HCC. Consecutive patients with ≤3 early-stage HCC lesions and tumor diameters ≤3 cm treated with RFA or radiotherapy were reviewed. RFA was the first choice for HCC unsuitable for surgery. Otherwise, stereotactic body radiotherapy in five fractions was mainly performed. For HCC adjacent to the gastrointestinal tract, radiotherapy with mild hypofractionation was performed. Propensity score matching was performed to reduce the selection bias between the RFA and radiotherapy groups. Between 2012 and 2016, a total of 231 patients with 474 tumors and 143 patients with 221 tumors were eligible and were treated with RFA and radiotherapy, respectively. In an unmatched comparison, the 3-year local recurrence rate was significantly lower for radiotherapy than for RFA (5.3%; 95% confidence interval [CI], 2.7-9.2; versus 12.9%, 95% CI, 9.9-16.2) (P < 0.01). A propensity score matching analysis of 106 patients in each group successfully matched the two treatment groups with regard to Barcelona Clinic Liver Cancer staging, T stage, and tumor size but not the adjacency of the tumor to risk organs or first or salvage treatment. The 3-year overall survival rates for RFA and radiotherapy patients were comparable (69.1%; 95% CI, 58.2-77.7; and 70.4%; 95% CI, 58.5-79.4, respectively; P = 0.86). Conclusion: Radiotherapy has excellent local control and comparable overall survival in patients with well-compensated liver function, exhibiting advantageous characteristics and compensating for the deficiencies of other treatment modalities; radiotherapy appears to be an acceptable alternative treatment option for patients who are not candidates for RFA.

Laparoscopic Microwave Ablation of Hepatocellular Carcinoma at Liver Surface: Technique Effectiveness and Long-Term Outcomes

Background and Aims:

To evaluate long-term outcomes and prognostic factors of laparoscopic microwave ablation as a first-line treatment for hepatocellular carcinoma located at the liver surface not feasible for percutaneous ablation.

Methods:

51 consecutive patients receiving laparoscopic microwave ablation in our center between January 11, 2012, and July 31, 2014, were enrolled. Technique effectiveness (complete ablation or incomplete ablation) was evaluated 1 month postprocedure. Procedure-related complications were recorded. The influences of patients’ baseline characteristics on recurrence-free survival and overall survival were analyzed after a median follow-up of 34.0 (ranging 19.0-49.0) months.

Results:

Complete ablation was gained in 47 (92.2%) of the 51 patients. No patients died within 30 days of microwave ablation procedure. A total of 3 (5.9%) cases of complications were observed. Tumor progression/recurrence were observed in 40 patients (78.4%). The median recurrence-free survival and median overall survival of the total cohort was 11.0 months (95% confidence interval: 7.573-14.427) and 34.0 months (95% confidence interval: 27.244-40.756), respectively. Multivariate analysis identified alanine transaminase level and tumor number as independent significant prognosticators of recurrence-free survival whereas α-fetoprotein level as significant prognosticators of overall survival.

Conclusions:

As a first-line treatment, laparoscopic microwave ablation provides high technique effectiveness rate and is well tolerated in patients with hepatocellular carcinoma located at liver surface. Alanine transaminase and tumor number were significant predictors of recurrence-free survival, whereas α-fetoprotein level was significant predictor of overall survival. Laparoscopic microwave ablation might serve as a rational treatment option for patients with hepatocellular carcinoma with tumors at the liver surface, which merits validation in future perspective studies.

Combination of radiofrequency ablation and transcatheter arterial chemoembolization to treat hepatocellular carcinoma: measurement of distance from needle tip to nodule for assessment of local tumor progression

OBJECTIVE

This study was performed to determine the relationship between the minimum distance from the radiofrequency ablation (RFA) needle tip to the tumor and local tumor progression (LTP) of hepatocellular carcinoma (HCC) nodules and identify prognostic factors for LTP.

METHODS

We reviewed 197 patients (197 nodules) who underwent RFA after transcatheter arterial chemoembolization for HCC from January 2010 to January 2015. Three-dimensional registration of images was used to calculate the minimum distance from the tip to the tumor. We then divided the minimum distance into two groups: <2 and ≥2 mm. Contrast-enhanced computed tomography was performed after treatment. The LTP rate was calculated 1 and 3 years after RFA. We performed multivariate analysis to identify independent prognostic factors for LTP.

RESULTS

The cumulative 1-year LTP rates in the <2- and ≥2-mm groups were 82.7% and 4.3%, respectively, and the cumulative 3-year LTP rates in the two groups were 94.8% and 10.8%, respectively. The minimum distance from the needle tip to the tumor was an independent prognostic factor for LTP.

CONCLUSIONS

A minimum distance of 2 mm from the needle tip to the tumor should be completely ablated along with the tumor.

Radiofrequency ablation following artificial ascites and pleural effusion creation may improve outcomes for hepatocellular carcinoma in high-risk locations

PURPOSE

To investigate the outcomes of radiofrequency ablation (RFA) following artificial ascites (AA) and artificial pleural effusion (AP) creation for hepatocellular carcinoma (HCC) in high-risk locations.

MATERIALS AND METHODS

Eligible patients were divided into 2 study periods (non-AAAP and AAAP groups) with AAAP performed in the latter period. Local tumor progression, primary technique effectiveness and complications were compared between patients with and without AAAP. Cumulative probability of local tumor progression and overall survival were estimated with Kaplan-Meier curves.

RESULTS

One hundred thirty-eight patients with 195 tumors were evaluated. AAAP was performed in 48 patients with 76 tumors. Local tumor progression rates at 12 and 24 months were 9.3% and 22.2% in the non-AAAP group versus 5.5% and 9% in the AAAP group (p < 0.0001). Primary technique effectiveness was achieved in 76.5% of the non-AAAP group versus 89.5% of the AAAP group (p = 0.046). Night (7.6%) major complications occurred in the non-AAAP group and 2 (2.6%) cases occurred in the AAAP group. Therapy-oriented severity grading system after RFA was lower in the AAAP group (p = 0.02). Overall survival rates at 12 and 24 months were 85.6% and 77.7% in the non-AAAP group versus 97.2% and 89.7% in the AAAP group (p = 0.033).

CONCLUSION

RFA following AA and AP for high-risk located HCC may improve outcomes.

Irreversible Electroporation as a Bridge to Liver Transplantation

Hepatocellular carcinoma (HCC) in proximity to major hepatic vasculature poses a risk for invasion, which would contraindicate liver transplantation, yet, is difficult to treat with thermal ablation. This study was undertaken to evaluate the feasibility of irreversible electroporation (IRE) as a bridge to transplantation for high-risk tumors. All patients with HCC in proximity to major hepatic vasculature treated with laparoscopic IRE as bridge to transplantation were studied. Patient and tumor characteristics, length of stay, and treatment-related complications were recorded. Tumor response was assessed with CT and explant pathology. Five patients with a median Model for End Stage Liver Disease (MELD) of 13 (7–21) underwent IRE. The median tumor size was 2.7 cm (1.5–3.7 cm). Adjacent structures included the right portal vein, hepatic veins/inferior vena cava (IVC) and left portal vein. Length of stay was one day for all patients. One patient suffered portal vein thrombosis. The transplant occurred at a median of 142 days (47–264) after IRE. Pathologic necrosis ranged from 30 to 100 per cent, without any vascular invasion. Four patients remain alive with no evidence of disease with median follow-up of 403 (227–623) days. The remaining patients died because of transplant-related complications onpost IRE day 297. IRE shows promise as a bridge to liver transplant for high risk HCC in a preliminary series, justifying further prospective evaluation.

Clinical Case Panel: Treatment Alternatives for Inoperable Hepatocellular Carcinoma

Surgical resection or liver transplantation offers the best chance of cure for patients with hepatocellular carcinoma (HCC). Unfortunately, most patients are not good candidates for liver resection due to locally advanced disease or compromised liver function. Moreover, liver transplantation waiting lists are long. For those cases not amenable for resection, a variety of local treatment modalities are available, such as image-guided ablative procedures, transarterial chemoembolization, and radioembolization, as well as external beam radiation. HCC presentation can vary considerably in size, number, and location of lesions. The management of inoperable HCC is, therefore, quite complex, and there is a lack of consensus on the best local treatment modality for each type tumor presentation. Here, we present 4 clinical case scenarios representative of commonly seen cases in the clinical setting, with different therapeutic perspectives from institutions with high expertise in the management of HCC.

Thermal ablation of intrahepatic cholangiocarcinoma: Safety, efficacy, and factors affecting local tumor progression

PURPOSE

To evaluate the safety and oncologic efficacy of percutaneous thermal ablation of intrahepatic cholangiocarcinoma (ICC) and identify risk factors for local tumor progression (LTP).

MATERIALS AND METHODS

Retrospective review of an institutional tumor ablation registry demonstrated that 20 patients (9 males, 11 females; mean age 62.5 ± 15.8 years) with 50 ICCs (mean size 1.8 ± 1.3 cm) were treated with percutaneous radiofrequency ablation (RFA) or microwave ablation (MWA) between 2006 and 2015. Thirty-eight of the treated ICCs (76%) were metastases that developed after surgical resection of the primary tumor. Patient demographics, procedure technical parameters, and clinical outcomes were reviewed. A Cox proportional hazards model was used to examine the risk of LTP by ablation modality. Survival analyses were performed using the Kaplan-Meier method.

RESULTS

Mean imaging follow-up time was 41.5 ± 42.7 months. Forty-four (88%) ICCs were treated with RFA, and 6 (12%) with MWA. Eleven (22%) cases of LTP developed in 5 (25%) patients. The median time to LTP among these 11 tumors was 7.1 months (range, 2.3-22.9 months). Risk of LTP was not significantly different for ICCs treated with MWA compared to RFA (HR 2.72; 95% CI 0.58-12.84; p = 03.21). Median disease-free survival was 8.2 months (1.1-70.4 months), and median overall survival was 23.6 months (7.4-122.5 months). No major complication occurred.

CONCLUSIONS

Percutaneous thermal ablation is a safe and effective treatment for patients with ICCs and may be particularly valuable in unresectable patients, or those who have already undergone hepatic surgery. Tumor size and ablation modality were not associated with LTP, whereas primary tumors and superficially located tumors were more likely to subsequently recur.

Radiofrequency ablation for subcardiac hepatocellular carcinoma: therapeutic outcomes and risk factors for technical failure

OBJECTIVES

To compare the therapeutic outcomes and safety of radiofrequency (RF) ablation for subcardiac and non-subcardiac hepatocellular carcinoma (HCC) and to evaluate the risk factors for technical failure of the procedure.

METHODS

This retrospective study was approved by the institutional review board. Between September 2002 and May 2016, 73 patients with subcardiac HCC and the same number of patients with non-subcardiac HCC matched by tumor size were included. Subcardiac HCC was defined as an index tumor that was located ≤ 1 cm from the pericardium in axial or coronal images. Cumulative local tumor progression (LTP) was compared between the two groups using the log-rank test. Prognostic factors for technical failure were assessed using multivariable logistic analysis.

RESULTS

Technical success rates between both groups were not significantly different (91.8% in the subcardiac HCC group vs. 95.9% in the non-subcardiac HCC group; p = 0.494). The cumulative LTP rates were 15.4% and 19.1% at 3 and 5 years, respectively, in the subcardiac HCC group, and 10.7% and 15.5% in the non-subcardiac HCC group, without significant difference (p = 0.862). The distance between the index tumor and pericardium (odds ratio [OR], 0.14; p = 0.023) and tumor in segment IV (reference, left lateral sector; OR, 36.53; p = 0.029) were significant factors for technical failure in patients with subcardiac HCC.

CONCLUSIONS

RF ablation was an effective treatment for subcardiac HCC. However, tumor location should be considered in the planning of treatment to avoid technical failure.

KEY POINTS

• RF ablation for subcardiac HCC is technically feasible without major complications. • RF ablation was an effective treatment for subcardiac HCC in terms of LTP. • Risk factors for technical failure were distance of the index tumor from the heart (cutoff value of 0.5 cm) and the location of the tumor (segment IV).

Comparison of Combined Therapy Using Conventional Chemoembolization and Radiofrequency Ablation Versus Conventional Chemoembolization for Ultrasound-Invisible Early-Stage Hepatocellular Carcinoma (Barcelona Clinic Liver Cancer Stage 0 or A)

Objective

To compare the therapeutic efficacy between conventional transarterial chemoembolization (cTACE) and combined therapy using cTACE and radiofrequency ablation (RFA) in ultrasound (US)-invisible early stage hepatocellular carcinoma (HCC).

Materials and Methods

From January 2008 to June 2016, 167 patients with US-invisible early stage HCCs were treated with cTACE alone (cTACE group; n = 85) or cTACE followed by immediate fluoroscopy-guided RFA targeting intratumoral iodized oil retention (combined group; n = 82). Procedure-related complications, local tumor progression (LTP), time to progression (TTP), and overall survival (OS) were compared between the two groups. Multivariate analyses were performed to identify prognostic factors.

Results

There was no major complication in either group. The cTACE group showed higher 1-, 3-, and 5-year LTP rates than the combined group; i.e., 12.5%, 31.7%, and 37.0%, respectively, in the cTACE group; compared to 7.3%, 16.5%, and 16.5%, respectively, in the combined group; p = 0.013. The median TTP was 18 months in the cTACE group and 24 months in the combined group (p = 0.037). Cumulative 1-, 3-, and 5-year OS rates were 100%, 93.2%, and 87.7%, respectively, in the cTACE group and 100%, 96.6%, and 87.4%, respectively, in the combined group (p = 0.686). Tumor diameter > 20 mm and cTACE monotherapy were independent risk factors for LTP and TTP.

Conclusion

Combined therapy using cTACE followed by fluoroscopy-guided RFA is a safe and effective treatment in US-invisible early stage HCCs. It provides less LTP and longer TTP than cTACE alone.

Tumor Location Influences Oncologic Outcomes of Hepatocellular Carcinoma Patients Undergoing Radiofrequency Ablation

Radiofrequency ablation (RFA) is recommended as a first-line therapy for small hepatocellular carcinoma (HCC). Tumor location is a potential factor influencing the procedure of RFA. To compare oncologic outcomes of RFA for different tumor locations, this retrospective study enrolled 194 patients with small HCC who had undertaken RFA. The HCC nodules were classified as peri-hepatic-vein (pHV) or non-pHV, peri-portal-vein (pPV) or non-pPV, and subcapsular or non-subcapsular HCC. The regional recurrence-free survival (rRFS), overall survival (OS), recurrence-free survival (recurrence in any location, RFS) and distant recurrence-free survival (dRFS) were compared. Operation failures were recorded in five pPV HCC patients, which was more frequent than in non-pPV HCC patients (p = 0.041). The 1-, 3-, and 5-year rRFS was 68.7%, 53.7%, and 53.7% for pHV patients and 85.1%, 76.1%, and 71.9% for non-pHV patients, respectively (p = 0.012). After propensity score matching, the 1-, 3-, and 5-year rRFS was still worse than that of non-pHV patients (p = 0.013). The OS, RFS, and dRFS were not significantly different between groups.

CONCLUSIONS

A pHV location was a risk factor for the regional recurrence after RFA in small HCC patients. The tumor location may not influence OS, RFS, and dRFS. Additionally, a pPV location was a potential high-risk factor for incomplete ablation.

Incomplete radiofrequency ablation promotes the development of CD133+ cancer stem cells in hepatocellular carcinoma cell line HepG2 via inducing SOX9 expression

BACKGROUND

Cancer stem cells (CSCs) accelerate the growth of hepatocellular carcinoma (HCC) residual after incomplete radiofrequency ablation (In-RFA). The present study aimed to detect the effects of In-RFA on stemness transcription factors (STFs) expression which are important for the production and function of CSCs, and to find which STFs promote HCC stemness after In-RFA.

METHODS

HepG2 cells were used for in vitro and in vivo studies. Flow cytometry and sphere-formation assays were used to detect the level and function of CD133⁺CSCs in the models. PCR array and ELISA were applied to analyze the altered expression of 84 STFs in CD133⁺CSCs in two models. Specific lentiviral shRNA was used to knockdown STFs expression, followed by detecting In-RFA's effects on the levels and function of CD133⁺CSCs.

RESULTS

In-RFA was identified to induce CD133⁺CSCs and increase their tumorigenesis ability in vitro and in vivo. The mRNA levels of 84 STFs in CD133⁺CSCs were detected by PCR array, showing that 15 and 22 STFs were up-regulated in two models, respectively. Meanwhile, the mRNA levels of seven common STFs were up-regulated in both models. ELISA assay demonstrated that only the protein of sex determining region Y-box 9 (SOX9) was up-regulated in both models, the protein levels of the other 6 common STFs did not increase in both models. Finally, SOX9 was identified to play an important role in inducing, maintaining stemness and promoting tumorigenesis ability of CD133⁺CSCs in both models.

CONCLUSION

In-RFA-induced SOX9 stimulates CD133⁺CSCs proliferation and increases their tumorigenesis ability, suggesting that SOX9 may be a good target for HCC treatment.

Microwave vs radiofrequency ablation for hepatocellular carcinoma within the Milan criteria: a propensity score analysis

BACKGROUND

Whether microwave ablation (MWA) challenges the standard role of radiofrequency ablation (RFA) in treating early-stage hepatocellular carcinoma (HCC) remains unclear.

AIM

To compare the efficacy of MWA vs RFA for treating primary HCC within the Milan criteria.

METHODS

From January 2002 to January 2017, the oncological outcomes after MWA (126 patients) and RFA (436 patients) were analysed by propensity score matching.

RESULTS

Before propensity score matching, for overall patients, MWA resulted in similar 5-year overall survival to RFA (80.1% vs 75.8%, P = 0.190) but better 5-year recurrence-free survival (28.1% vs 19.6%, P = 0.036). For solitary HCC ≤ 3 cm, MWA resulted in comparable 5-year overall survival (81.8% vs 77.1%, P = 0.170) to RFA but better 5-year recurrence-free survival (34.6% vs 24.0%, P = 0.042). After propensity score matching, MWA resulted in better 5-year overall survival (79.3% vs 68.4%, P = 0.021) and 5-year recurrence-free survival (27.9% vs 6.4%, P < 0.001) than RFA for HCC. For solitary HCC ≤3 cm, MWA resulted in comparable 5-year overall survival (81.2% vs 66.3%, P = 0.062) and 5-year recurrence-free survival (37.7% vs 17.4%, P = 0.088) to RFA. In Cox analysis, RFA modality, tumours located in risk areas and low serum albumin levels were unfavourable prognostic factors for overall survival. RFA modality, multiple tumours, tumour size and low serum albumin levels were unfavourable prognostic factors for recurrence-free survival (all P < 0.05).

CONCLUSIONS

RFA is inferior to MWA for treating HCC within the Milan criteria, but has comparable efficacy to MWA for solitary HCC ≤ 3 cm.

Radiofrequency ablation vs. surgery for perivascular hepatocellular carcinoma: Propensity score analyses of long-term outcomes

BACKGROUND & AIMS

The therapeutic outcomes of surgical resection (SR) or radiofrequency ablation (RFA) for perivascular hepatocellular carcinoma (HCC) have not been compared. The aim of this study was to compare SR with RFA as first-line treatment in patients with perivascular HCC and to evaluate the long-term outcomes of both therapies.

METHODS

This retrospective study was approved by the institutional review board. The requirement for informed consent was waived. Between January 2006 and December 2010, a total of 283 consecutive patients with small perivascular HCCs (≤3 cm, Barcelona Clinic Liver Cancer stage 0 or A) underwent SR (n = 182) or RFA (n = 101) as a first-line treatment. The progression-free survival (PFS) and overall survival (OS) rates were compared by propensity score matching. Subgroup analysis of these outcomes was conducted according to the type of hepatic vessels.

RESULTS

The median follow-up was 7.8 years. Matching yielded 62 pairs of patients. In the two matched groups, the PFS rates at 5 and 10 years were 58.0% and 17.8%, respectively, in the SR group, and 25.4% and 14.1%, respectively, in the RFA group (p <0.001). The corresponding OS rates at 5 and 10 years were 93.5% and 91.9% in the SR group and 82.3% and 74.1% in the RFA group, respectively (p <0.001). In contrast to those in patients with perivenous HCCs, subgroup analysis indicated that extrahepatic recurrence and OS were significantly different according to the treatment modality in patients with periportal HCCs (p = 0.004 and p <0.001, respectively).

CONCLUSIONS

In patients with small perivascular HCCs, SR provided better long-term tumor control and OS than RFA, particularly for periportal tumors.

LAY SUMMARY

Surgical resection and radiofrequency ablation are both treatment options for perivascular hepatocellular carcinoma. We compared outcomes in patients treated with either method. Surgical resection provided better long-term tumor control and overall survival than radiofrequency ablation for patients with a small perivascular hepatocellular carcinoma (≤3 cm) as a first-line treatment, particularly for periportal tumors. The location of the tumor and the type of peritumoral hepatic vessels need to be considered when choosing between surgical resection and radiofrequency ablation for small HCCs.

Hepatocellular carcinoma recurrence in hepatitis C virus-related cirrhosis treated with direct-acting antivirals: a case-control study

BACKGROUND

Direct-acting antivirals (DAAs) therapy against hepatitis C viral (HCV) infection has markedly improved the sustained viral response. However, recent studies have suggested an unsuspected high rate of hepatocellular carcinoma (HCC) recurrence.

PATIENTS AND METHODS

A retrospective case-control study was carried out to investigate the impact of DAAs on tumor recurrence in patients with complete response to HCC treatment within our HCV-related cirrhosis cohort. Patients who received [group 1 (G1), n=22] or not [group 2 (G2), n=49] a DAAs therapy were matched 1 : 2 for age, sex, liver function, HCC stage, and treatment.

RESULTS

Initial HCC were mostly Barcelona Clinic Liver Cancer stage A (95% G1, 94% G2). Sustained viral response with DAAs was achieved in 86% of patients. After a similar median overall follow-up time with similar radiologic surveillance after HCC treatment, 41% of patients developed radiologic tumor recurrence in G1 versus 35% of patients in G2 (P=0.7904). There was no significant difference in time to progression between the two groups [12 (9-16) months G1 vs. 14 (8-21) months G2, P=0.7688], or Barcelona Clinic Liver Cancer stage at recurrence. However, the interval between HCC treatment and antiviral therapy was significantly different among DAAs patients with recurrence and those without recurrence [7.0 (2.5-9.0) months vs. 36.0 (9.0-58.0) months, P=0.0235, respectively].

CONCLUSION

In our case-control study, HCV therapy with DAAs does not accelerate or prevent early HCC recurrence compared with untreated patients. The rate of recurrence, time to progression, and HCC pattern are similar. Early DAAs treatment (<12 months) after HCC cure should be discouraged considering the HCC recurrence rate during this period.

Effect of oral antiviral treatment on long-term outcomes of radiofrequency ablation therapy for hepatitis B virus-related hepatocellular carcinoma

OBJECTIVES

This study aimed to investigate the effect of oral antiviral treatment on the prognosis of hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) after radiofrequency (RF) ablation.

METHODS

Between January 2003 and December 2010, 228 patients without a history of antiviral treatment were treated with RF ablation for a single HBV-related HCC. We divided the patients into two groups, patients who received (n=125) or did not receive antiviral treatment (n=103), based on whether oral antiviral treatment was administered after RF ablation. The median duration of antiviral treatment was 60.1 months. HCC recurrence and overall survival were compared in the two groups in the full cohort and the propensity score-matched cohort.

RESULTS

In the matched cohort, the probability of HCC recurrence at 5 years was 43.8% for the non-antiviral treatment group and 14.7% for the antiviral treatment group (p<0.001). The probability of overall survival at 5 years was 77.2% for the non-antiviral treatment group and 93.5% for the antiviral treatment group (p=0.002). Multivariable analysis showed that risk factors for HCC recurrence included large tumor size (hazard ratio (HR)=1.30, p=0.022), HBV DNA serum level (HR=1.11, p=0.005), and serum AFP level ≥20 ng/mL (HR=1.66, p=0.005). Overall survival was associated with larger tumor size (HR=1.86, p=0.001) and Child-Pugh Class B (HR=2.13, p=0.019). Oral antiviral treatment after RF ablation was significantly associated with a lower risk of tumor recurrence and death (HR=0.33, p<0.001, and HR=0.44, p=0.004).

CONCLUSION

Use of oral antiviral treatment after curative RF ablation was associated with favorable outcomes in terms of tumor recurrence and overall survival in patients with HBV-related HCC.

Electrochemotherapy as treatment option for hepatocellular carcinoma, a prospective pilot study

BACKGROUND AND OBJECTIVES

Electrochemotherapy provides non-thermal ablation of cutaneous as well as deep seated tumors. Based on positive results of the treatment of colorectal liver metastases, we conducted a prospective pilot study on hepatocellular carcinomas with the aim of testing the feasibility, safety and effectiveness of electrochemotherapy.

PATIENTS AND METHODS

Electrochemotherapy with bleomycin was performed on 17 hepatocellular carcinomas in 10 patients using a previously established protocol. The procedure was performed during open surgery and the patients were followed for median 20.5 months.

RESULTS

Electrochemotherapy was feasible for all 17 lesions, and no treatment-related adverse events or major post-operative complications were observed. The median size of the treated lesions was 24 mm (range 8-41 mm), located either centrally, i.e., near the major hepatic vessels, or peripherally. The complete response rate at 3-6 months was 80% per patient and 88% per treated lesion.

CONCLUSIONS

Electrochemotherapy of hepatocellular carcinoma proved to be a feasible and safe treatment in all 10 patients included in this study. To evaluate the effectiveness of this method, longer observation period is needed; however the results at medium observation time of 20.5 months after treatment are encouraging, in 15 out of 17 lesions complete response was obtained. Electrochemotherapy is predominantly applicable in patients with impaired liver function due to liver cirrhosis and/or with lesions where a high-risk operation is needed to achieve curative intent, given the intra/perioperative risk for high morbidity and mortality.

Comparison of Transarterial Chemoembolization Combined with Radiofrequency Ablation Therapy versus Surgical Resection for Early Hepatocellular Carcinoma

Both radiofrequency ablation (RFA) and surgical resection (SR) are radical treatment recommended for early hepatocellular carcinoma (HCC). Transarterial chemoembolization (TACE) is a palliative treatment for intermediate HCC, and TACE1RFA combined therapy is considered superior to TACE or RFA alone for management of early HCC. This systematic review compared the efficacy and safety of TACE1RFA combined therapy with SR for early HCC. Web of Science, PubMed, EMBASE, and the Cochrane Library were searched for literatures related with our topic. The primary endpoint was overall survival (OS), and the secondary endpoint was the recurrence-free survival (RFS) rate; safety was measured by the rate of major complications. The effect sizes of OS, RFS, and local progression rates were expressed by odds ratio (OR), while the effect size of complications was presented using relative risk. TACE1RFA combined therapy and SR had a similar 1-year OS rate [OR: 1.84; 95% confidence interval (CI): 0.82, 4.14; P > 0.05], 3-year OS rate (OR: 0.84; 95% CI: 0.43, 1.67; P > 0.05), 1-year RFS rate (OR: 0.77; 95% CI: 0.53, 1.11; P > 0.05), and 3-year RFS rate (OR: 0.88; 95% CI: 0.48, 1.42; P > 0.05) for early HCC. However, the 5-year OS rate (OR: 0.54; 95% CI: 0.40, 0.73; P < 0.05) and 5-year RFS rate (OR: 0.49; 95% CI: 0.27, 0.90; P < 0.05) were lower in patients with TACE1RFA than in those with SR. SR is associated with better long-term survival outcomes and a lower recurrence rate than TACE1RFA for patients with early HCC and is the optimal choice for patients with early HCC.

Development of an Electroporation and Nanoparticle-based Therapeutic Platform for Bone Metastases

Purpose To assess for nanopore formation in bone marrow cells after irreversible electroporation (IRE) and to evaluate the antitumoral effect of IRE, used alone or in combination with doxorubicin (DOX)-loaded superparamagnetic iron oxide (SPIO) nanoparticles (SPIO-DOX), in a VX2 rabbit tibial tumor model. Materials and Methods All experiments were approved by the institutional animal care and use committee. Five porcine vertebral bodies in one pig underwent intervention (IRE electrode placement without ablation [n = 1], nanoparticle injection only [n = 1], and nanoparticle injection followed by IRE [n = 3]). The animal was euthanized and the vertebrae were harvested and evaluated with scanning electron microscopy. Twelve rabbit VX2 tibial tumors were treated, three with IRE, three with SPIO-DOX, and six with SPIO-DOX plus IRE; five rabbit VX2 tibial tumors were untreated (control group). Dynamic T2*-weighted 4.7-T magnetic resonance (MR) images were obtained 9 days after inoculation and 2 hours and 5 days after treatment. Antitumor effect was expressed as the tumor growth ratio at T2*-weighted MR imaging and percentage necrosis at histologic examination. Mixed-effects linear models were used to analyze the data. Results Scanning electron microscopy demonstrated nanopores in bone marrow cells only after IRE (P , .01). Average volume of total tumor before treatment (503.1 mm³ ± 204.6) was not significantly different from those after treatment (P = .7). SPIO-DOX was identified as a reduction in signal intensity within the tumor on T2*-weighted images for up to 5 days after treatment and was related to the presence of iron. Average tumor growth ratios were 103.0% ± 75.8 with control treatment, 154.3% ± 79.7 with SPIO-DOX, 77% ± 30.8 with IRE, and -38.5% ± 24.8 with a combination of SPIO-DOX and IRE (P = .02). The percentage residual viable tumor in bone was significantly less for combination therapy compared with control (P = .02), SPIO-DOX (P , .001), and IRE (P = .03) treatment. The percentage residual viable tumor in soft tissue was significantly less with IRE (P = .005) and SPIO-DOX plus IRE (P = .005) than with SPIO-DOX. Conclusion IRE can induce nanopore formation in bone marrow cells. Tibial VX2 tumors treated with a combination of SPIO-DOX and IRE demonstrate enhanced antitumor effect as compared with individual treatments alone. ^© RSNA, 2017 Online supplemental material is available for this article.

Radiofrequency Ablation Combined With Transarterial Chemoembolization for Specially Located Small Hepatocellular Carcinoma

OBJECTIVE

To investigate the safety and efficacy of radiofrequency ablation combined with transarterial chemoembolization in patients with specially located small hepatocellular carcinoma.

MATERIALS AND METHODS

Between March 2014 and March 2017, a total of 26 patients with 26 lesions (10 perivascular, 6 subdiaphragmatic, 5 subcapsular, 5 perivascular, and subdiaphragmatic location; mean diameter 2.12 (0.62) cm), who received radiofrequency ablation-transarterial chemoembolization treatment, were retrospectively analyzed. Local tumor response was assessed by computed tomography/magnetic resonance imaging 1 month after the procedure. Tumor-free survival was also assessed according to the modified Response Evaluation Criteria in Solid Tumors. Complications were evaluated according to the National Cancer Institute's Common Terminology Criteria for Adverse Events (version 4.0).

RESULTS

Complete response was achieved in all patients 1 month after the procedure. During a median follow-up duration of 16.76 months (95% confidence interval: 7.78-25.73 months), local tumor recurrence occurred in 2 patients and new intrahepatic lesions developed in 7 patients. The 1-, 2-, and 3-year cumulative local tumor progression rates were 3.84%, 7.69%, and 7.69%, respectively. The median tumor-free survival duration was 21.96 months (95% confidence interval: 17.58-26.34 months). The 1-, 2-, and 3-year tumor-free survival rates were 67.4%, 46.1%, and 39.3%, respectively.

CONCLUSION

The radiofrequency ablation-transarterial chemoembolization combination therapy appears to be safe and effective and might be a treatment option for specially located small hepatocellular carcinoma lesions that have a risk of incomplete ablation or major complications.

Is early recurrence of hepatocellular carcinoma in HCV cirrhotic patients affected by treatment with direct-acting antivirals? A prospective multicentre study

BACKGROUND

Data on HCV-related hepatocellular carcinoma (HCC) early recurrence in patients whose HCC was previously cured, and subsequently treated by direct-acting antivirals (DAAs), are equivocal.

AIM

To assess the risk of HCC early recurrence after DAAs exposure in a large prospective cohort of HCV-cirrhotic patients with previous successfully treated HCC, also looking for risk factors for cancer early recurrence.

METHODS

We enrolled 143 consecutive patients with complete response after curative treatment of HCC, subsequently treated with DAAs and monitored by the web-based RESIST-HCV database. Clinical, biological, and virological data were collected. The primary endpoint was the probability of HCC early recurrence from DAA starting by Kaplan-Meier method.

RESULTS

Eighty-six per cent of patients were in Child-Pugh class A and 76% of patients were BCLC A. Almost all patients (96%) achieved sustained virological response. Twenty-four HCC recurrences were observed, with nodular or infiltrative pattern in 83% and 17% of patients, respectively. The 6-, 12- and 18-month HCC recurrence rates were 12%, 26.6% and 29.1%, respectively. Main tumour size and history of prior HCC recurrence were independent risk factors for HCC recurrence by Cox multivariate model.

CONCLUSIONS

Probability of HCC early recurrence in patients who had HCC previously cured remains high, despite HCV eradication by DAAs. Risk was comparable but not higher to that reported in literature in DAA-untreated patients. Previous HCC recurrence and tumour size can be used to stratify the risk of HCC early recurrence. Further studies are needed to assess impact of DAAs on late recurrence and mortality.

Midterm Safety and Efficacy of Irreversible Electroporation of Malignant Liver Tumors Located Close to Major Portal or Hepatic Veins

Purpose To investigate the efficacy and safety of irreversible electroporation (IRE) in the treatment of hepatic tumors not suitable for thermal ablation (radiofrequency ablation [RFA] or microwave ablation). Materials and Methods This was an institutional review board-approved prospective study in 29 patients (15 men, 14 women; mean age, 63 years ± 12 [standard deviation]) with 43 primary (n = 8) or secondary (n = 35) malignant liver tumors who underwent computed tomography (CT)-guided IRE. All target tumors were located immediately adjacent to major hepatic veins, portal veins, or both; thus, they were not considered suitable for RFA or microwave ablation. Patients underwent postinterventional CT and magnetic resonance (MR) imaging. Systematic follow-up MR imaging was performed for 24 months on average to assess complete ablation, intrahepatic tumor recurrence, and complications. The 95% confidence intervals (CIs) were determined for the rate of bile duct strictures, incomplete ablation, and tumor recurrence. Results Complete ablation was achieved in 40 (93%; 95% CI: 85, 100) of 43 target tumors, with a safety margin of 5-10 mm, and was confirmed at immediate postinterventional CT and MR imaging. In 13 (33%; 95% CI: 18, 47) of 40 completely ablated tumors, intrahepatic tumor recurrence was observed at 2-18 months. However, only two (15%; 95% CI: 0, 35) of these 13 tumors were observed within the ablation zone. In the remaining 11 (85%; 95% CI: 65, 100), tumor growth was observed alongside the needle tract. None of the two true local recurrences occurred at the site of the vessel. All adjacent vessels remained perfused at follow-up. Five (24%; 95% CI: 5, 39) of 21 patients with target tumors adjacent to portal veins developed mild to moderate cholestasis 2-6 weeks after IRE. Conclusion IRE is useful to avoid incomplete ablation secondary to heat-sink effects and damage to major blood vessels; however, needle tract seeding is observed in 26% of treated tumors, and IRE induces sufficient local heating to bile ducts in 24% of ablations. ^© RSNA, 2017.

Loco-regional treatment of HCC: current status

Hepatocellular carcinoma (HCC) represents one of the few cancers for which locoregional treatments are recognised as being able to cure and/or prolong survival and are included in international guidelines. This is due to the unique nature of HCC, in most cases occurring in patients with underlying virus- or alcohol-related cirrhosis. The treatment choice in patients with HCC is therefore driven not only by tumour staging, as in the great majority of cancers, but also by careful evaluation of liver function and physical status. Another specific feature of HCC is that it is the only tumour that can be cured by organ transplantation, with the aim of treating both the cancer and underlying liver disease. These characteristics configure a complex scenario and prompt the need for close cooperation among interventional oncologists, surgeons, hepatologists, and anaesthesiologists. In patients with limited hepatic disease, preserved hepatic function and good performance status, categorised as very early and early-stage HCC according to the Barcelona Clinic Liver Cancer (BCLC) classification, image-guided tumour ablation is included among the curative treatments. More than half of patients with HCC are, however, diagnosed late, despite the widespread implementation of surveillance programmes, when curative treatments cannot be applied. For patients presenting with multinodular HCC and relatively preserved liver function, absence of cancer-related symptoms, and no evidence of vascular invasion or extrahepatic spread transcatheter arterial chemoembolisation (TACE) is the current standard of care. Although anti-tumour activity and promising survival results has been reported in cohorts of patients with advanced HCC treated with radio-embolisation, systemic treatment with the multi-kinase inhibitor, sorafenib, is still recommended for patients at this stage. In this article, current treatment strategies for HCC according to tumour stage are discussed, underlining the latest advances in the literature and technical developments.

Evaluation of hepatocellular carcinoma tumor vascularity using contrast-enhanced ultrasonography as a predictor for local recurrence following radiofrequency ablation

PURPOSE

The purpose of this study was to evaluate whether the hypervascularity of hepatocellular carcinomas (HCCs) on contrast-enhanced ultrasonography (CEUS) prior to radiofrequency ablation (RFA) is a significant risk factor for local recurrence after RFA.

MATERIALS AND METHODS

Institutional review board approval and informed consent were obtained. Overall, 208 patients (mean age, 71.7 years; range, 50-87 years; 137 men, 71 women) with 282 HCCs treated with RFA were analyzed retrospectively. The mean maximum tumor diameter was 15.7mm. We compared the abilities of CEUS and contrast-enhanced computed tomography (CECT) to detect hypervascularity in HCCs. We then classified the HCCs into two groups according to the arterial-phase CEUS findings: a "hypervascular group" with whole or partial hypervascular areas within the lesions compared with the surrounding liver parenchyma, and a "non-hypervascular group" with isovascular or hypovascular areas within the lesions. We assessed the cumulative rate of local recurrence after RFA, and we also evaluated the risk factors for local recurrence using a univariate analysis.

RESULTS

The detection rate for hypervascular HCCs was significantly higher using CEUS (78%, 221/282) than that using CECT (66%, 186/282) (P<0.001). Using the CEUS findings, the cumulative rate of local recurrence was significantly higher in the hypervascular group (41.2%, 56/221) than in the non-hypervascular group (18.4%, 6/61) (P=0.007). A univariate analysis revealed that hypervascularity on CEUS was an independent risk factor for local recurrence (P=0.010).

CONCLUSION

Hypervascularity in HCCs as observed using CEUS is a significant risk factor for local recurrence after RFA.

Real-time US-CT/MR fusion imaging for percutaneous radiofrequency ablation of hepatocellular carcinoma

BACKGROUND & AIMS

Although ultrasonography (US) guided radiofrequency ablation (RFA) is a commonly used treatment option for early hepatocellular carcinoma (HCC), inconspicuous tumors on US limits its feasibility. Thus, we prospectively determined whether real-time US-CT/MR fusion imaging can improve the technical feasibility of RFA compared with B-mode US, and help predict local tumor progression after RFA in patients with HCC.

METHODS

A total of 216 patients with 243 HCCs ⩽5cm referred for RFA were prospectively enrolled. Prior to RFA, the operators scored the visibility of tumors, and technical feasibility on a 4-point scale at both B-mode US and fusion imaging. RFA was performed with a switching monopolar system using a separable cluster electrode under fusion imaging guidance. Technique effectiveness, local tumor progression and intrahepatic remote recurrences were evaluated.

RESULTS

Tumor visibility and technical feasibility were significantly improved with fusion imaging compared with B-mode US (p<0.001). Under fusion imaging guidance, the technique effectiveness of RFA for invisible tumors on B-mode US was similar to those for visible tumors (96.1% vs. 97.6%, p=0.295). Estimated cumulative incidence of local tumor progression at 24months was 4.7%, and previous treatment for other hepatic tumors (p=0.01), higher expected number of electrode insertions needed and lower technical feasibility scores (p<0.01) on fusion imaging were significant negative predictive factors for local tumor progression.

CONCLUSION

Real-time fusion imaging guidance significantly improved the tumor visibility and technical feasibility of RFA in patients with HCCs compared with B-mode US, and low feasibility scores on fusion imaging was a significant negative predictive factor for local tumor progression.

LAY SUMMARY

US/CT-MR fusion imaging guidance improved the tumor visibility and technical feasibility of RFA in patients with HCCs. In addition, fusion imaging guided RFA using multiple electrodes demonstrated a high technique effectiveness rate and a low local tumor progression rate during mid-term follow-up. Clinical trial number: ClinicalTrials.gov number, NCT02687113.

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.

Evaluation of tolerability and efficacy of irreversible electroporation (IRE) in treatment of Child-Pugh B (7/8) hepatocellular carcinoma (HCC)

INTRODUCTION

Few studies have assessed the tolerability and efficacy of irreversible electroporation (IRE) in the treatment of Child-Pugh B (7/8) patients with hepatocellular carcinoma (HCC). Based on its mechanism of action, we hypothesized that IRE would be superior to microwave (MW) ablation and compared the liver tolerance and ablation success rates of these therapies in Child-Pugh B patients with HCC.

METHODS

55 patients with Child-Pugh B (7/8) HCC were treated with either MW ablation (n = 25) or IRE (n = 30). Tolerance and ablation success were evaluated at 30 and 90 days and 90 days and 6 months, respectively. Tolerance was defined as stable liver function and absence of increased ascites or worsening portal hypertension. Ablation success was defined as tumor eradication on triple phase contrasted computed tomography (CT).

RESULTS

Patients undergoing IRE had shorter length of stay (p = 0.05) and 90 day readmission rate (p = 0.03) than those undergoing MW ablation. Additionally, IRE was better tolerated than MW ablation at 30 and 90 days. IRE and MW ablation resulted in 6 month success rates of 97% and 100%.

CONCLUSION

Treatment of Child-Pugh B (7/8) HCC with IRE results in equivalent ablation success with improved liver tolerance compared with MW ablation and other ablative modalities.

Outcomes of laparoscopic hepatic resection versus percutaneous radiofrequency ablation for hepatocellular carcinoma located at the liver surface: A case-control study with propensity score matching

AIM

Percutaneous radiofrequency ablation (P-RFA) therapy is a widely applied treatment for small hepatocellular carcinoma (HCC); however, local recurrence is a major issue of HCC located at the surface of the liver (surface HCC). The aim of this study was to compare the outcome of laparoscopic hepatic resection (LH) and P-RFA for surface HCC in case-control patient groups using the propensity score.

METHODS

Between 2011 and 2013, 40 and 52 patients underwent LH and P-RFA for surface HCC (≤3 cm, 1-3 nodules). To correct the difference in clinicopathological factors between the two groups, propensity score matching was used at a 1:1 ratio, which resulted in a comparison of 27 patients/group. We compared outcomes between the two groups, with special reference to local recurrence.

RESULTS

Clinicopathological variables were well balanced between the two groups. One patient in the LH group was converted to open surgery due to adhesion. The incidence of complications was 0% in the P-RFA group and 15% (four patients) in the LH group (P = 0.11); however, none of these four patients in the LH group sustained severe complications. The duration of hospitalization following treatment was longer in the LH group than in the P-RFA group (12.6 vs 7.6 days, P < 0.01). The incidence of local recurrence was lower in the LH group (0%) than in the P-RFA group (eight patients [30%], P = 0.004).

CONCLUSION

LH is an effective treatment for surface HCC with regard to control of local recurrence.

Phase 2 study of stereotactic body radiotherapy and optional transarterial chemoembolization for solitary hepatocellular carcinoma not amenable to resection and radiofrequency ablation

BACKGROUND

Curative treatment options for patients with early stage hepatocellular carcinoma (HCC) include resection, liver transplantation, and percutaneous ablation therapy. However, even patients with solitary HCC are not always amenable to these treatments. The authors prospectively investigated the clinical outcomes of patients who received stereotactic body radiotherapy (SBRT) for solitary HCC.

METHODS

A phase 2 study involving SBRT and optional transarterial chemoembolization (TACE) was conducted in patients with Child-Pugh grade A or B and underlying, solitary HCC (greatest tumor dimension, ≤4 cm) who were unsuitable candidates for resection and radiofrequency ablation. The prescription dose was 35 to 40 grays in 5 fractions. The primary endpoint was 3-year local tumor control.

RESULTS

From 2007 to 2012, 101 patients were enrolled, and 90 were evaluable with a median follow-up of 41.7 months (range, 6.8-96.2 months). Thirty-two patients were treatment-naïve, 20 were treated for newly diagnosed intrahepatic failure, and 38 were treated for residual or recurrent HCC as salvage therapy. Thirty-two patients did not receive TACE, 48 received insufficient TACE, and 10 attained full lipiodol accumulation. The 3-year local control rate was 96.3%, the 3-year liver-related cause-specific survival rate was 72.5%, and the overall survival rate was 66.7%. Grade 3 laboratory abnormalities were observed in 6 patients, and 8 patients had Child-Pugh scores that worsened by 2 points.

CONCLUSIONS

SBRT achieved high local control and overall survival with feasible toxicities for patients with solitary HCC, despite rather stringent conditions. SBRT can be effective against solitary HCC in treatment-naive, intrahepatic failure, residual disease, and recurrent settings, taking advantage of its distinctive characteristics. Cancer 2016;122:2041-9. © 2016 American Cancer Society.

Three-dimensional quantitative assessment of ablation margins based on registration of pre- and post-procedural MRI and distance map

PURPOSE

Contrast-enhanced MR images are widely used to confirm the adequacy of ablation margin after liver ablation for early prediction of local recurrence. However, quantitative assessment of the ablation margin by comparing pre- and post-procedural images remains challenging. We developed and tested a novel method for three-dimensional quantitative assessment of ablation margin based on non-rigid image registration and 3D distance map.

METHODS

Our method was tested with pre- and post-procedural MR images acquired in 21 patients who underwent image-guided percutaneous liver ablation. The two images were co-registered using non-rigid intensity-based registration. After the tumor and ablation volumes were segmented, target volume coverage, percent of tumor coverage, and Dice similarity coefficient were calculated as metrics representing overall adequacy of ablation. In addition, 3D distance map around the tumor was computed and superimposed on the ablation volume to identify the area with insufficient margins. For patients with local recurrences, the follow-up images were registered to the post-procedural image. Three-dimensional minimum distance between the recurrence and the areas with insufficient margins was quantified.

RESULTS

The percent tumor coverage for all nonrecurrent cases was 100 %. Five cases had tumor recurrences, and the 3D distance map revealed insufficient tumor coverage or a 0-mm margin. It also showed that two recurrences were remote to the insufficient margin.

CONCLUSIONS

Non-rigid registration and 3D distance map allow us to quantitatively evaluate the adequacy of the ablation margin after percutaneous liver ablation. The method may be useful to predict local recurrences immediately following ablation procedure.

Long-term Therapeutic Outcomes of Radiofrequency Ablation for Subcapsular versus Nonsubcapsular Hepatocellular Carcinoma: A Propensity Score Matched Study

Purpose To compare the long-term therapeutic outcomes of radiofrequency (RF) ablation for hepatocellular carcinoma (HCC) in subcapsular versus nonsubcapsular locations by using propensity score matching. Materials and Methods RF ablation for subcapsular HCC is controversial because of a high risk of incomplete ablation or major complications. This retrospective study was approved by the institutional review board, and the requirement for informed consent was waived. Between April 2006 and December 2011, 508 consecutive patients (396 men, 112 women; age range, 30-80 years) with a single HCC (Barcelona Clinic Liver Cancer stage 0 or A) underwent ultrasonography-guided percutaneous RF ablation as a first-line treatment. The patients were divided into two groups according to tumor location: subcapsular (n = 227) and nonsubcapsular (n = 281). Subcapsular HCC was defined as an index tumor located within 0.1 cm of the liver capsule. The association of subcapsular location and therapeutic outcomes of RF ablation was evaluated, including (a) local tumor progression (LTP) by using a competing risk regression model and (b) overall survival (OS) by using a Cox proportional hazards model according to propensity score matched data. The major complication rates from both overall data and matched data were assessed. Results Matching yielded 163 matched pairs of patients. In the two matched groups, cumulative LTP rates were 18.8% and 20.9% at 3 and 5 years, respectively, in the subcapsular group and 13.2% and 16.0% in the nonsubcapsular group. Corresponding OS rates were 90.7% for 3 years and 83.2% for 5 years in the subcapsular group and 91.4% and 79.1%, respectively, in the nonsubcapsular group. Hazard ratios (HRs) for LTP (HR = 1.37, P = .244) and OS (HR = 0.86, P = .604) were not significantly different between the two matched groups. Additionally, differences in major complication rates were not significant between groups for the two sets of data (P > .05). Conclusion The differences in LTP, OS, and major complication rates of RF ablation for HCC were not significant between subcapsular and nonsubcapsular groups. (©) RSNA, 2016.

Liver Ablation: Best Practice

Tumor ablation in the liver has evolved to become a well-accepted tool in the management of increasing complex oncologic patients. At present, percutaneous ablation is considered first-line therapy for very early and early hepatocellular carcinoma and second-line therapy for colorectal carcinoma liver metastasis. Because thermal ablation is a treatment option for other primary and secondary liver tumors, an understanding of the underlying tumor biology is important when weighing the potential benefits of ablation. This article reviews ablation modalities, indications, patient selection, and imaging surveillance, and emphasizes technique-specific considerations for the performance of percutaneous ablation.

Minimal invasive treatments for liver malignancies

Minimal invasive therapies have proved useful in the management of primary and secondary hepatic malignancies. The most relevant aspects of all these therapies are their minimal toxicity profiles and highly effective tumor responses without affecting the normal hepatic parenchyma. These unique characteristics coupled with their minimally invasive nature provide an attractive therapeutic option for patients who previously may have had few alternatives. Combination of these therapies might extend indications to bring curative treatment to a wider selected population. The results of various ongoing combination trials of intraarterial therapies with targeted therapies are awaited to further improve survival in this patient group. This review focuses on the application of ablative and intra-arterial therapies in the management of hepatocellular carcinoma and hepatic colorectal metastasis.

Transarterial chemoembolization in hepatocellular carcinoma treatment: Barcelona clinic liver cancer staging system

Hepatocellular carcinoma (HCC), the fifth most common cancer that predominantly occurs in liver cirrhosis patients, requires staging systems to design treatments. The barcelona clinic liver cancer staging system (BCLC) is the most commonly used HCC management guideline. For BCLC stage B (intermediate HCC), transarterial chemoembolization (TACE) is the standard treatment. Many studies support the use of TACE in early and advanced HCC patients. For BCLC stage 0 (very early HCC), TACE could be an alternative for patients unsuitable for radiofrequency ablation (RFA) or hepatic resection. In patients with BCLC stage A, TACE plus RFA provides better local tumor control than RFA alone. TACE can serve as bridge therapy for patients awaiting liver transplantation. For patients with BCLC B, TACE provides survival benefits compared with supportive care options. However, because of the substantial heterogeneity in the patient population with this stage, a better patient stratification system is needed to select the best candidates for TACE. Sorafenib represents the first line treatment in patients with BCLC C stage HCC. Sorafenib plus TACE has shown a demonstrable effect in delaying tumor progression. Additionally, TACE plus radiotherapy has yielded better survival in patients with HCC and portal venous thrombosis. Considering these observations together, TACE clearly has a critical role in the treatment of HCC as a stand-alone or combination therapy in each stage of HCC. Diverse treatment modalities should be used for patients with HCC and a better patient stratification system should be developed to select the best candidates for TACE.

Multidisciplinary perspective of hepatocellular carcinoma: A Pacific Northwest experience

Hepatocellular carcinoma (HCC) is the most rapidly increasing type of cancer in the United States. HCC is a highly malignant cancer, accounting for at least 14000 deaths in the United States annually, and it ranks third as a cause of cancer mortality in men. One major difficulty is that most patients with HCC are diagnosed when the disease is already at an advanced stage, and the cancer cannot be surgically removed. Furthermore, because almost all patients have cirrhosis, neither chemotherapy nor major resections are well tolerated. Clearly there is need of a multidisciplinary approach for the management of HCC. For example, there is a need for better understanding of the fundamental etiologic mechanisms that are involved in hepatocarcinogenesis, which could lead to the development of successful preventive and therapeutic modalities. It is also essential to define the cellular and molecular bases for malignant transformation of hepatocytes. Such knowledge would: (1) greatly facilitate the identification of patients at risk; (2) prompt efforts to decrease risk factors; and (3) improve surveillance and early diagnosis through diagnostic imaging modalities. Possible benefits extend also to the clinical management of this disease. Because there are many factors involved in pathogenesis of HCC, this paper reviews a multidisciplinary perspective of recent advances in basic and clinical understanding of HCC that include: molecular hepatocarcinogenesis, non-invasive diagnostics modalities, diagnostic pathology, surgical modality, transplantation, local therapy and oncological/target therapeutics.