Minimally invasive image-guided therapies for hepatocellular carcinoma

A novel radiomics approach for predicting TACE outcomes in hepatocellular carcinoma patients using deep learning for multi-organ segmentation

Transarterial chemoembolization (TACE) represent the standard of therapy for non-operative hepatocellular carcinoma (HCC), while prediction of long term treatment outcomes is a complex and multifactorial task. In this study, we present a novel machine learning approach utilizing radiomics features from multiple organ volumes of interest (VOIs) to predict TACE outcomes for 252 HCC patients. Unlike conventional radiomics models requiring laborious manual segmentation limited to tumoral regions, our approach captures information comprehensively across various VOIs using a fully automated, pretrained deep learning model applied to pre-TACE CT images. Evaluation of radiomics random survival forest models against clinical ones using Cox proportional hazard demonstrated comparable performance in predicting overall survival. However, radiomics outperformed clinical models in predicting progression-free survival. Explainable analysis highlighted the significance of non-tumoral VOI features, with their cumulative importance superior to features from the largest liver tumor. The proposed approach overcomes the limitations of manual VOI segmentation, requires no radiologist input and highlight the clinical relevance of features beyond tumor regions. Our findings suggest the potential of this radiomics models in predicting TACE outcomes, with possible implications for other clinical scenarios.

Local-Regional Treatment of Hepatocellular Carcinoma: A Primer for Radiologists

The treatment planning for patients with hepatocellular carcinoma (HCC) relies predominantly on tumor burden, clinical performance, and liver function test results. Curative treatments such as resection, liver transplantation, and ablative therapies of small lesions should be considered for all patients with HCC. However, many patients are ineligible for these treatments owing to advanced disease stage and comorbidities. Despite efforts to increase screening, early-stage HCC remains difficult to diagnose, which decreases the possibility of curative therapies. In this context, local-regional treatment of HCC is accepted as a form of curative therapy in selected patients with early-stage disease, as a therapeutic option in patients who are not eligible to undergo curative therapies, as a downstaging approach to decrease tumor size toward meeting the criteria for liver transplantation, and as a bridging therapy to avoid tumor growth while the patient is on the waiting list for liver transplantation. The authors review the indications, types, mechanism of action, and possible complications of local-regional treatment, as well as the expected postprocedural imaging features of HCC. Furthermore, they discuss the role of imaging in pre- and postprocedural settings, provide guidance on how to assess treatment response, and review the current limitations of imaging assessment. Finally, the authors summarize the potential future directions with imaging tools that may add value to contemporary practice at response assessment and imaging biomarkers for patient selection, treatment response, and prognosis. ©RSNA, 2022.

Hepatocellular carcinoma locoregional therapies: Outcomes and future horizons

Hepatocellular carcinoma (HCC) is the most common primary cancer of the liver and has an overall five-year survival rate of less than twenty percent. For patients with unresectable disease, evolving liver-directed locoregional therapies provide efficacious treatment across the spectrum of disease stages and via a variety of catheter-directed and percutaneous techniques. Goals of locoregional therapies in HCC may include curative intent in early-stage disease, bridging or downstaging to surgical resection or transplantation for early or intermediate-stage disease, and local disease control and palliation in advanced-stage disease. This review explores the outcomes of chemoembolization, bland embolization, radioembolization, and percutaneous ablative therapies. Attention is also given to prognostic factors related to each of the respective techniques, as well as future directions of locoregional therapies for HCC.

Periportal fields cause stronger cooling effects than veins in hepatic microwave ablation: an in vivo porcine study

BACKGROUND

Vascular cooling effects are a well-known source for tumor recurrence in thermal in situ ablation techniques for hepatic malignancies. Microwave ablation (MWA) is an ablation technique to be considered in the treatment of malignant liver tumors. The impact of vascular cooling in MWA is still controversial.

PURPOSE

To evaluate the influence of different intrahepatic vessel types, vessel sizes, and vessel-to-antenna-distances on MWA geometry in vivo.

MATERIAL AND METHODS

Five MWAs (902-928 MHz) were performed with an energy input of 24.0 kJ in three porcine livers in vivo. MWA lesions were cut into 2-mm slices. The minimum and maximum radius of the ablation area was measured for each slice. Distances were measured from ablation center toward all adjacent hepatic vessels with a diameter of ≥1 mm and within a perimeter of 20 mm around the antenna. The respective vascular cooling effect relative to the maximum ablation radius was calculated.

RESULTS

In total, 707 vessels (489 veins, 218 portal fields) were detected; 370 (76%) hepatic veins and 185 (85%) portal fields caused a cooling effect. Portal fields resulted in higher cooling effects (37%) than hepatic veins (26%, P < 0.01). No cooling effect could be observed in close proximity of vessels within the central ablation zone.

CONCLUSION

Hepatic vessels influenced MWA zones and caused a distinct cooling effect. Portal fields resulted in more pronounced cooling effect than hepatic veins. No cooling effect was observed around vessels situated within the central white zone.

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Computed tomography-guided radiofrequency ablation combined with transarterial embolization assisted by a three-dimensional visualization ablation planning system for hepatocellular carcinoma in challenging locations: a preliminary study

OBJECTIVE

To assess the clinical efficacy and safety of computed tomography-guided radiofrequency ablation(CT-RFA) combined with transarterial embolization(TAE) assisted by a three-dimensional visualization ablation planning system(3DVAPS) for hepatocellular carcinoma(HCC) in challenging locations.

METHODS

Data from 62 treatment-naive patients with hepatocellular carcinoma(HCC), with 83 lesions in challenging locations, and who met the Milan criteria and underwent CT-RFA between June 2013 and June 2016 were reviewed. Patients were divided into one of two groups according to different treatment modalities: study group (TAE combined with RFA assisted by 3DVAPS [n = 32]); and control (RFA only [n = 30]). Oncological outcomes included ablation-related complications, local tumor progression (LTP), and overall survival (OS). Univariate and multivariate Cox proportional hazards regression analyses were performed to assess risk factors associated with LTP and OS.

RESULTS

HCC lesions (mean size, 1.9 ± 1.0 mm in diameter) abutting the gastrointestinal tract (n = 25), heart and diaphragm (n = 21), major vessels (n = 13), and gallbladder (n = 3) were treated. A significant difference was detected in LTP between the two groups (P = 0.034), with no significant difference in OS between the two groups (P = 0.193). There were no severe complications related to ablation. Univariate analysis revealed that sex (P = 0.046) and child-turcotte-pugh (CTP) grade (P<0.001) were risk factors for OS, whereas CTP grade and treatment method (P<0.001) were risk factors for LTP. Multivariate analysis revealed that CTP grade B (P = 0.005) was independently associated with poor OS, and RFA alone (P<0.001) was independently associated with poor LTP.

CONCLUSION

CT-RFA combined with TAE assisted by a 3DVAPS provided ideal clinical efficiency for HCC in challenging locations and was a highly safe treatment modality.

Computed tomography-guided radiofrequency ablation of the retained iodized oil after simultaneous combination with transarterial embolization in small recurrent or residual hepatocellular carcinoma

Objective

To assess the clinical efficacy and safety of transarterial embolization (TAE) in simultaneous combination with computed tomography (CT)-guided radiofrequency ablation (RFA) for recurrent or residual hepatocellular carcinoma (HCC), and to determine the risk factors influencing local tumor progression following this procedure.

Methods

One hundred eighteen patients with recurrent or residual HCC (tumor size, 10-30 ​mm) underwent RFA. During the 19-month follow-up, 59 patients received RFA only (RFA group), and the remaining 59 received RFA immediately after TAE (TAE ​+ ​RFA group). All patients were followed up to observe the short-term therapeutic effects and complications. The cumulative local tumor progression rates in both groups were calculated using unpaired Student's t tests and the Kaplan-Meier method.

Results

The rate of major complications was 5.08% in the TAE ​+ ​RFA group and 3.39% in the RFA group. The overall response rate was 96.61% in the TAE ​+ ​RFA group and 79.66% in the RFA group (P ​= ​0.008). The disease control rate was significantly higher in the TAE ​+ ​RFA group than in the RFA group (94.92% vs. 79.66%, P ​= ​0.024). The median time to local tumor progression was 4.8 months in the RFA group and 9.6 months in the TAE ​+ ​RFA group. The cumulative local tumor progression rate at 1 year was 10.60% in the RFA group and 23.60% in the TAE ​+ ​RFA group (P ​= ​0.016).

Conclusion

TAE in simultaneous combination with CT-guided RFA was effective and safe against recurrent or residual HCC. Local tumor progression can be minimized by the complete ablation of targeted iodized oil deposits after simultaneous TAE.

Ultrasound-guided percutaneous microwave ablation vs. surgical resection for thoracoabdominal wall implants from hepatocellular carcinoma: intermediate-term results

OBJECTIVE

The aims of this study were to compare the clinical outcomes between ultrasound (US)-guided percutaneous microwave ablation (MWA) and surgical resection (SR) in patients with thoracoabdominal wall implants from hepatocellular carcinom (HCC) and to identify the prognostic factors associated with the two treatment methods.

MATERIALS AND METHODS

A total of 47 patients (mean age, 56.7 ± 15.9 years, range, 18-78 years; 34 men and 13 women) with 61 thoracoabdominal wall HCC seeding were included from April 2007 to May 2017. Twenty-five patients underwent US-guided MWA and 22 patients underwent SR. Survival, recurrence and liver function were compared between the two groups. Effect of changes in key parameters (i.e. overall survival (OS), disease-free survival (DFS) and local tumour reoccurrence-free (LTRF)) was statistically analysed with the log-rank test. Univariate and multivariate analyses were performed on several clinicopathological variables to identify factors affecting long-term outcome and recurrence.

RESULTS

The OS, DFS and LTRF after MWA were comparable to those of SR (p =0.493, p = 0.578 and p =0.270, respectively). Estimated 5-year overall survival rates were 63% after MWA and 48.1% after SR; for disease-free survival, estimated 5-year rates were 67.5% after MWA and 48.8% after SR; estimated 24-month LTRF rates were 71.3% after MWA and 87.8% after SR. The MWA group had less surgical time (p = <0.001), estimated blood loss (p = <0.001) and post-operative hospitalisation (p = 0.032) and cost (p = 0.015). Multivariate analysis showed remnant intrahepatic tumour (p =0.007), Child Pugh grade (p = 0.009) and metastasis (p= <0.001), were predictors for survival rate.

CONCLUSIONS

Ultrasound-guided percutaneous MWA is a safe and effective treatment method for metastatic HCC on the thoracoabdominal wall with similar outcomes to SR. Residual intrahepatic HCC, Child Pugh grade and distant metastasis are predictors for survival.

HZ-6d targeted HERC5 to regulate p53 ISGylation in human hepatocellular carcinoma

Manipulating the posttranslational modulator of p53 is central in the regulation of its activity and function. ISGylated p53 can be degraded by the 20S proteasome. During this process, HERC5/Ceb1, an IFN-induced HECT-type E3 ligase, mediated p53 ISGylation. In this study, we indicated that HERC5 was over-expressed in both HCC tissue samples and cell lines. Knockdown of HERC5 significantly induced the expression of p53, p21 and Bax/Bcl-2 in HCC cells, resulting in apoptosis augment. Whereas, opposite results were obtained by using HERC5 over-expression. On this basis, we screened a 7, 11-disubstituted quinazoline derivative HZ-6d that could bind to the HERC5 G-rich sequence in vitro. Interestingly, HZ-6d injection effectively delayed the growth of xenografts in nude mice. In vitro, HZ-6d significantly inhibited cell growth, suppressed cell migration, induced apoptosis in HCC cells. Further studies demonstrated the anti-cancer effect of HZ-6d was associated with down-regulation of HERC5 and accumulation of p53. Collectively, we demonstrated that HZ6d is a HERC5 G-quadruplex ligand with anti-tumor properties, an action that may offer an attractive idea for restoration of p53 function in cancers.