Radiologic criteria of response to systemic treatments for hepatocellular carcinoma

The Evolving Scenario in the Assessment of Radiological Response for Hepatocellular Carcinoma in the Era of Immunotherapy: Strengths and Weaknesses of Surrogate Endpoints

Hepatocellular carcinoma (HCC) is a challenging malignancy characterised by clinical and biological heterogeneity, independent of the stage. Despite the application of surveillance programs, a substantial proportion of patients are diagnosed at advanced stages when curative treatments are no longer available. The landscape of systemic therapies has been rapidly growing over the last decade, and the advent of immune-checkpoint inhibitors (ICIs) has changed the paradigm of systemic treatments. The coexistence of the tumour with underlying cirrhosis exposes patients with HCC to competing events related to tumour progression and/or hepatic decompensation. Therefore, it is relevant to adopt proper clinical endpoints to assess the extent of treatment benefit. While overall survival (OS) is the most accepted endpoint for phase III randomised controlled trials (RCTs) and drug approval, it is affected by many limitations. To overcome these limits, several clinical and radiological outcomes have been used. For instance, progression-free survival (PFS) is a useful endpoint to evaluate the benefit of sequential treatments, since it is not influenced by post-progression treatments, unlike OS. Moreover, radiological endpoints such as time to progression (TTP) and objective response rate (ORR) are frequently adopted. Nevertheless, the surrogacy between these endpoints and OS in the setting of unresectable HCC (uHCC) remains uncertain. Since most of the surrogate endpoints are radiology-based (e.g., PFS, TTP, ORR), the use of standardised tools is crucial for the evaluation of radiological response. The optimal way to assess the radiological response has been widely debated, and many criteria have been proposed over the years. Furthermore, none of the criteria have been validated for immunotherapy in advanced HCC. The coexistence of the underlying chronic liver disease and the access to several lines of treatments highlight the urgent need to capture early clinical benefit and the need for standardised radiological criteria to assess cancer response when using ICIs in mono- or combination therapies. Here, we review the most commonly used clinical and radiological endpoints for trial design, as well as their surrogacy with OS. We also review the criteria for radiological response to treatments for HCC, analysing the major issues and the potential future perspectives.

Clinical application of advances and innovation in radiation treatment of hepatocellular carcinoma

Background:

Hepatocellular carcinoma (HCC) management has evolved over the past two decades, with the development of newer treatment modalities. While various options are available, unmet needs are reflected through the mixed treatment outcome for intermediate-stage HCC. As HCC is radiosensitive, radiation therapies have a significant role in management. Radiation therapies offer local control for unresectable lesions and for patients who are not surgical candidates. Radiotherapy also provides palliation in metastatic disease, and acts as a bridge to resection and transplantation in selected patients. Advancements in radiotherapy modalities offer improved dose planning and targeted delivery, allowing for better tumor response and safer dose escalations while minimizing the risks of radiation-induced liver damage. Radiotherapy modalities are broadly classified into external beam radiation therapy and selective internal radiation therapy. With emerging modalities, radiotherapy plays a complementary role in the multidisciplinary care of HCC patients.

Aim:

We aim to provide an overview of the role and clinical application of radiation therapies in HCC management.

Relevance for Patients:

The continuous evolution of radiotherapy techniques allows for improved therapeutic outcomes while mitigating unwanted adverse effects, making it an attractive modality in HCC management. Rigorous clinical studies, quality research and comprehensive datasets will further its application in the present era of evidence-based practice in Medicine.

Sorafenib is associated with a reduced rate of tumour growth and liver function deterioration in HCV-induced hepatocellular carcinoma

BACKGROUND & AIMS

Sorafenib has been the standard of care for patients with advanced hepatocellular carcinoma and although immunotherapeutic approaches are now challenging this position, it retains an advantage in HCV-seropositive patients. We aimed to quantify the rate of tumour progression in patients receiving sorafenib and relate this figure to survival, both overall, and according to viral status.

METHODS

Using serial data from an international clinical trial we applied a joint model to combine survival and progression over time in order to estimate the rate of tumour growth as assessed by tumour burden and serum alpha-fetoprotein, and the impact of treatment on liver function.

RESULTS

High tumour burden at baseline was associated with an increased risk of death. In patients still alive at the end of the study, the progression in relation to tumour burden was very low compared to those who died within the study. Overall, the change in mean tumour burden was 0.12 mm per day or an absolute growth rate of 3.6 mm/month. Median doubling time was 665 days. For those who progressed above 0.12 mm per day or the 12% rate, median survival was 234 days compared to 384 days if the rate was below 12%. Tumour growth rate and serum alpha-fetoprotein rise were significantly lower in those who were HCV seropositive as was the rate of decline in liver function. These results were replicated in 2 independent patient groups.

CONCLUSION

Our analysis suggests that sorafenib treatment is associated with improved survival in patients with advanced hepatocellular carcinoma mainly by decreasing the rate of tumour growth and liver function deterioration among patients with HCV infection.

LAY SUMMARY

Among patients receiving sorafenib for advanced hepatocellular carcinoma the rate of tumour growth (as assessed by changes in tumour size and the biomarker alpha-fetoprotein) and the deterioration of liver function is less in those who have the hepatitis C virus, than in those who do not.

Evaluation of the LI-RADS treatment response algorithm in hepatocellular carcinoma after trans-arterial chemoembolization

PURPOSE

To evaluate the diagnostic performance of LI-RADS treatment response algorithm (LR-TRA) and modified RECIST (mRECIST) for the detection of viable hepatocellular carcinoma (HCC) on MRI after trans-arterial chemoembolization (TACE).

MATERIALS AND METHODS

This retrospective study includes cirrhotic patients that underwent trans-arterial chemoembolization prior to liver transplantation from 2013 to 2017 with a pre- and post-treatment MRI available. Three blinded readers assigned a LR-TRA and mRECIST category to each lesion. Lesions on MRI and explant pathology were matched and characterized as complete (100% necrosis) or incomplete necrosis (≤99% necrosis). Diagnostic performance of LR-TRA and mRECIST were calculated with a generalized estimating equation.

RESULTS

A total of 52 patients with 71 lesions were included, 47 with incomplete and 24 with complete necrosis. In consensus, 45 lesions were categorized as LR-TR Nonviable, of which 62.2% (28/45) had incomplete and 37.8% (17/45) had complete necrosis. Six lesions were categorized as LR-TR Equivocal, of which 33.3% (2/6) had incomplete and 66.7% (4/6) had complete necrosis. Twenty lesions were categorized as LR-TR Viable of which 85.0% (17/20) had incomplete and 15.0% (3/20) had complete necrosis. The sensitivity of LR-TR Viable for detecting incompletely necrotic tumor when LR-TR Equivocal was considered as viable, in consensus was 40.4%; specificity 70.8%; accuracy 50.7%. The sensitivity of mRECIST for detecting incompletely necrotic tumor was 37.0%; specificity 79.2%; accuracy 51.4%. There was no significant difference in diagnostic performance between mRECIST and LR-TRA (p = 0.14-0.33). Agreement for LR-TRA category was moderate (k = 0.53 [95% CI: 0.45, 0.67]).

CONCLUSION

LI-RADS treatment response algorithm demonstrates high specificity and low to moderate sensitivity for the detection of viable HCC after TACE in a North American cirrhotic cohort, without significant difference in diagnostic performance between LR-TRA and mRECIST.

A simplified method to quantitatively predict the effect of lenvatinib on hepatocellular carcinoma using contrast-enhanced ultrasound with perfluorobutane microbubbles

Contrast-enhanced computed tomography (CECT) is generally used to evaluate the response to treatment of hepatocellular carcinoma (HCC); however, CECT is unsuitable for the early prediction of therapeutic effects and frequent monitoring. We aimed to investigate the usefulness of our simplified method for the quantification of tumor vascularity using contrast-enhanced ultrasound (CEUS) with perfluorobutane microbubbles [Sonazoid^® (GE Healthcare, Oslo, Norway)] to predict the therapeutic effect of lenvatinib. Among the 13 patients studied, nine who had more than a 20% reduction in tumor vascularity within 2 weeks of starting treatment experienced complete response or partial response at 8-12 weeks as assessed by CECT. In contrast, three patients without reductions and one patient with only a slight decrease in tumor vascularity had a poor response to lenvatinib. Quantitative assessment of tumor vascularity by our simplified CEUS-based method could be a useful predictor of therapeutic responses to lenvatinib in patients with HCC.

Regorafenib Combined with Other Systemic Therapies: Exploring Promising Therapeutic Combinations in HCC

Regorafenib was the first drug to demonstrate a survival benefit as a second-line agent after sorafenib failure in patients with unresectable hepatocellular carcinoma (HCC). Recent studies have shown that its mechanism of action is not only limited to its very broad spectrum of inhibition of angiogenesis, tumor proliferation, spread, and metastasis, but also to its immunomodulatory properties that have favorable effects on the very intricate role that the tumor microenvironment plays in carcinogenesis and tumor growth. In this review, we discuss rationale and evidence supporting regorafenib efficacy in HCC and that led to its approval as a second-line treatment, after sorafenib failure. We also discuss the evidence from clinical practice studies that confirm the results previously achieved in clinical trials. Finally, we analyze the potential role of regorafenib in emerging combined treatment approach with immunotherapy strategies using immune checkpoint blockade and its potential extension to patient categories not included in the registrative study.

Evaluation of the Benefits of TACE Combined with Sorafenib for Hepatocellular Carcinoma Based on Untreatable TACE (unTACEable) Progression

Purpose

Outcomes after the treatment for unresectable or advanced-stage hepatocellular carcinoma (HCC) are unsatisfied. We evaluated the therapeutic benefits of a combination therapy strategy for these patients through transarterial chemoembolization (TACE) plus sorafenib.

Patients and Methods

In total, 85 patients with HCC classified as intermediate and advanced stage from June 2012 to November 2017 were retrospectively investigated. We divided patients into the monotherapy (n=43; TACE alone) and combined therapy (n=42; TACE plus sorafenib) groups.

Results

Compared with the TACE alone group, the TACE plus sorafenib experienced significantly prolonged progression-free survival (PFS) (mean 21 months vs 12 months; P = 0.0005) and overall survival (OS) (mean 32 months vs 21 months; P = 0.0157). The disease control rate (DCR) of TACE plus sorafenib group was 80.95%, which was significantly increased than the TACE alone group (55.81%) (P<0.05), as well as objective response rate (ORR) (23.81% vs 16.28%). Besides, the rates of liver-related AEs and liver failure in the TACE plus sorafenib group were not increased in contrast to TACE alone group, and there were no new safety concerns. To sum up, the superiority of combination therapy with significantly prolonging progression-free and overall survival was observed, meanwhile finding a significant increase in tumor response rate and manageable safety in the combined therapy in contrast to the monotherapy group.

Conclusion

Based on unTACEble progression, the superiority of the combination therapy is that TACE plus sorafenib has been bringing about significantly better outcomes compared with TACE alone for HCC patients.

Experience with regorafenib in the treatment of hepatocellular carcinoma

Regorafenib is a diphenylurea oral multikinase inhibitor, structurally comparable to sorafenib, which targets a variety of kinases implicated in angiogenic and tumor growth-promoting pathways. Regorafenib was the first agent to positively show significant survival advantage as a second-line therapy in patients with unresectable hepatocellular carcinoma (HCC) who had previously failed first-line treatment with sorafenib. Recent evidence has shown that its antitumor efficacy is due to a comprehensive spectrum of tumor neo-angiogenesis and proliferation inhibition and immunomodulatory effects on the tumor microenvironment, which plays a crucial role in tumor development. This review addresses the rationale and supporting evidence for regorafenib's efficacy in HCC that led to regorafenib's approval as a second-line therapy. In addition, we review proof from clinical practice studies that validate the RESORCE trial results. We discuss regorafenib's potential role in the newly emerging therapeutic strategy based on combination with immune checkpoint blockade and its possible extensibility to patient categories not enrolled in the registrative study.

Association of Addition of Ablative Therapy Following Transarterial Chemoembolization With Survival Rates in Patients With Hepatocellular Carcinoma

IMPORTANCE

Hepatocellular carcinoma (HCC) is a heterogeneous disease with many available treatment modalities. Transarterial chemoembolization (TACE) is a valuable treatment modality for HCC lesions. This article seeks to evaluate the utility of additional ablative therapy in the management of patients with HCC who received an initial TACE procedure.

OBJECTIVE

To compare the overall survival (OS) and freedom from local progression (FFLP) outcomes after TACE alone with TACE that is followed by an ablative treatment regimen using stereotactic body radiation therapy, radiofrequency ablation, or microwave ablation for patients with HCC.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study of 289 adults at a single urban medical center examined survival outcomes for patients with nonmetastatic, unresectable HCC who received ablative therapies following TACE or TACE alone from January 2010 through December 2018. The Lee, Wei, Amato common baseline hazard model was applied for within-patient correlation with robust variance and Cox regression analysis was used to assess the association between treatment group (TACE vs TACE and ablative therapy) and failure time events (FFLP per individual lesion and OS per patient), respectively. In both analyses, the treatment indication was modeled as a time-varying covariate. Landmark analysis was used as a further sensitivity test for bias by treatment indication.

EXPOSURES

TACE alone vs TACE followed by ablative therapy.

MAIN OUTCOMES AND MEASURES

Freedom from local progression and overall survival. Hypotheses were generated before data collection.

RESULTS

Of the 289 patients identified, 176 (60.9%) received TACE only and 113 (39.1%) received TACE plus ablative therapy. Ablative therapy included 45 patients receiving stereotactic body radiation therapy, 39 receiving microwave ablation, 20 receiving radiofrequency ablation, and 9 receiving a combination of these following TACE. With a median (interquartile range) follow-up of 17.4 (9.5-29.5) months, 242 of 512 (47.3%) lesions progressed, 211 in the group with TACE alone and 31 in the group with TACE plus ablative therapy (P < .001). Over 3 years, FFLP was 28.1% for TACE alone vs 67.4% for TACE with ablative therapy (P < .001). The 1-year and 3-year OS was 87.5% and 47.1% for patients with lesions treated with TACE alone vs 98.7% and 85.3% for patients where any lesion received TACE plus ablative therapy, respectively (P = .01), and this benefit remained robust on landmark analyses at 6 and 12 months. The addition of ablative therapy was independently associated with OS on multivariable analysis for all patients (hazard ratio, 0.26; 95% CI, 0.13-0.49; P < .001) and for patients with Barcelona clinic liver cancer stage B or C disease (hazard ratio, 0.31; 95% CI, 0.14-0.69; P = .004).

CONCLUSIONS AND RELEVANCE

Adding ablative therapy following TACE improved FFLP and OS among patients with hepatocellular carcinoma. This study aims to guide the treatment paradigm for HCC patients until results from randomized clinical trials become available.

Molecular and Metabolic Imaging of Hepatic Neuroendocrine Tumors Following Radioembolization with 90Y-microspheres

Liver is the predominant site of metastatization for neuroendocrine tumors (NETs). Up to 75% of patients affected by intestinal NETs present liver metastases at diagnosis. For hepatic NET, surgery represents the most effective approach but is often unfeasible due to the massive involvement of multifocal disease. In such cases, chemotherapy, peptide receptor radionuclide therapy and loco-regional treatments may represent alternative therapeutic options. In particular, radioembolization with 90Y-microspheres has been introduced as a novel technique for treating hepatic malignant lesions, combining the principles of embolization and radiation therapy. In order to evaluate the response to 90Y-radioembolization, standard radiologic criteria have been demonstrated to present several limitations. 18Fluoro-deoxyglucose (FDG) Positron Emission Tomography (PET) is routinely used for monitoring the response to therapy in oncology. Nevertheless, NETs often present low glycolytic activity thus the conventional 18FDG PET may not be adequate for these tumors. For many years, somatostatin receptor scintigraphy (SRS) with 111In-pentetreotide has been used for diagnosis and staging of NETs. More recently, three 68Ga-DOTA-compounds have been developed and introduced for the imaging of NETs with PET technology. The aim of the present paper was to review the existing literature concerning the application of different metabolic and molecular probes for the imaging evaluation of hepatic NETs following 90Y-RE.

2019 Update of Indian National Association for Study of the Liver Consensus on Prevention, Diagnosis, and Management of Hepatocellular Carcinoma in India: The Puri II Recommendations

Hepatocellular carcinoma (HCC) is one of the major causes of morbidity, mortality, and healthcare expenditure in patients with chronic liver disease in India. The Indian National Association for Study of the Liver (INASL) had published its first guidelines on diagnosis and management of HCC (The Puri Recommendations) in 2014, and these guidelines were very well received by the healthcare community involved in diagnosis and management of HCC in India and neighboring countries. However, since 2014, many new developments have taken place in the field of HCC diagnosis and management, hence INASL endeavored to update its 2014 consensus guidelines. A new Task Force on HCC was constituted that reviewed the previous guidelines as well as the recent developments in various aspects of HCC that needed to be incorporated in the new guidelines. A 2-day round table discussion was held on 5th and 6th May 2018 at Puri, Odisha, to discuss, debate, and finalize the revised consensus statements. Each statement of the guideline was graded according to the Grading of Recommendations Assessment Development and Evaluation system with minor modifications. We present here the 2019 Update of INASL Consensus on Prevention, Diagnosis, and Management of Hepatocellular Carcinoma in India: The Puri-2 Recommendations.

Cytoplasmic translocation of nuclear LSD1 (KDM1A) in human hepatoma cells is induced by its inhibitors

Aim

Histone-modifiable lysine-specific demethylase-1 (LSD1/KDM1A) is an oncoprotein upregulated in cancers, including hepatoma. We previously reported that the hepatoma-preventive geranylgeranoic acid (GGA) inhibits KDM1A at the same IC₅₀ as that of the clinically used tranylcypromine. Here, we report that these inhibitors induce the cytoplasmic translocation of nuclear KDM1A in a human hepatoma-derived cell line.

Methods & results

Immunofluorescence studies revealed that KDM1A was cytoplasmically localized in HuH-7 cells 3 h after GGA or tranylcypromine addition. However, GGA did not affect the subcellular localization of another histone lysine-specific demethylase, KDM5A. This suggests that GGA-induced translocation is KDM1A specific.

Conclusion

These data demonstrate, for the first time, that KDM1A inhibitors specifically induce the cytoplasmic translocation of nuclear KDM1A.

Inter-operator variability and source of errors in tumour response assessment for hepatocellular carcinoma treated with sorafenib

OBJECTIVES

To assess the inter-operator concordance and the potential sources of discordance in defining response to sorafenib in hepatocellular carcinoma (HCC).

METHODS

All patients who received sorafenib between September 2008 and February 2015 were scrutinised for this retrospective study. Images were evaluated separately by three radiologists with different expertise in liver imaging (operator 1, >10 years; operator 2, 5 years; operator 3, no specific training in liver imaging), according to: response evaluation radiological criteria in solid tumours (RECIST) 1.1, modified RECIST (mRECIST) and response evaluation criteria in cancer of the liver (RECICL).

RESULTS

The overall response concordance between the more expert operators was good, irrespective of the criteria (RECIST 1.1, ĸ = 0.840; mRECIST, ĸ = 0.871; RECICL, ĸ = 0.819). Concordance between the less expert operator and the other colleagues was lower. The most evident discordance was in target lesion response assessment, with expert operators disagreeing mostly on lesion selection and less expert operators on lesion measurement. As a clinical correlate, overall survival was more tightly related with "progressive disease" as assessed by the expert compared to the same assessment performed by operator 3.

CONCLUSIONS

Decision on whether a patient is a responder or progressor under sorafenib may vary among different operators, especially in case of a non-specifically trained radiologist. Regardless of the adopted criteria, patients should be evaluated by experienced radiologists to minimise variability in this critical instance.

KEY POINTS

• Inter-operator variability in the assessment of response to sorafenib is poorly known. • The concordance between operators with expertise in liver imaging was good. • Target lesions selection was the main source of discordance between expert operators. • Concordance with non-specifically trained operator was lower, independently from the response criteria. • The non-specifically trained operator was mainly discordant in measurements of target lesions.