Clinical feasibility and efficacy of stereotactic body radiotherapy for hepatocellular carcinoma: A systematic review and meta-analysis of observational studies. Radiother Oncol. 2019;131:135-144. [PMID: 30773180 DOI: 10.1016/j.radonc.2018.12.005]

Prospective planning comparison of magnetic resonance-guided vs. internal target volume-based stereotactic body radiotherapy of hepatic metastases - Which patients do really benefit from an MR-linac?

Purpose/objective

To compare online MR-guided SBRT (MRgRT) of liver metastases with state-of-the-art ITV-based SBRT (ITV-SBRT) and assess which patients benefit most from MRgRT.

Materials and methods

In a prospective randomized trial (MAESTRO study, NCT05027711), patients were randomized to either gated and online adaptive MRgRT or ITV-SBRT if a biologically effective dose (BED10) of 100 Gy was feasible with ITV-SBRT. Otherwise, patients were treated with MRgRT. In this subgroup analysis of 20 patients, a dosimetric comparison of MRgRT and ITV-SBRT plans was performed. Tumor control and normal tissue complication probabilities were calculated.

Results

In 40 % of all patients, MRgRT enabled SBRT with less fractions and/or higher prescription BED10. Almost all target volume metrics were improved with MRgRT. MRgRT PTV D95% was significantly higher in the overall cohort (91.0 ± 22.9 Gy vs. 79.5 ± 27.2 Gy, p = 0.001), in uncritical (111.3 ± 6.2 Gy vs. 104.7 ± 4.1 Gy, p = 0.022) and in critical cases with limited healthy liver volume or nearby gastrointestinal organs at risk (74.1 ± 16.9 Gy vs. 58.5 ± 18.5 Gy, p = 0.041). Target volume V100% was also superior with MRgRT. Calculated 2-year tumor control probability was significantly superior with MRgRT overall (73.0 ± 6.2 % vs. 69.7 ± 7.9 %, p = 0.002), in uncritical cases (78.3 ± 1.4 % vs. 76.8 ± 1.0 %, p = 0.022) and in critical cases (68.5 ± 4.8 % vs. 63.8 ± 5.8 %, p = 0.041), without elevated normal tissue complication probability.

Conclusion

Dosimetrically, gated MRgRT was beneficial for virtually all the hepatic metastases analyzed in this study. Patients with metastases located critically near gastrointestinal OAR or with limited healthy liver volume should be allocated to centers providing MRgRT.

Dosimetric investigation of multi-parametric 4D-MRI for radiotherapy in liver cancer

BACKGROUND

In radiotherapy, inadequate management of organ motion in liver cancer may lead to inadequate delineation accuracy, resulting in the underdosage of target tissues and overdosage of surrounding normal tissues. To investigate the clinical potential of multi-parametric 4D-MRI in the target delineation and dose accuracy for liver cancer radiotherapy.

METHODS

Twenty patients receiving radiotherapy for liver cancer were enrolled. Each patient underwent contrast-enhanced planning CT (free-breathing), contrast-enhanced T1-weighted (free-breathing), T2-weighted (gated) 3D-MRI, and low-quality 4D-MRI using the time resolved imaging with interleaved stochastic trajectories volumetric interpolated breath-hold examination (TWIST-VIBE) sequence. A dual-supervised deformation estimation model was used to generate a 4D deformable vector field (4D-DVF) from 4D-MRI data, and the prior images were deformed using this 4D-DVF to generate multi-parametric 4D-MRI. Assisted by 3D-MRI and multi-parametric 4D-MRI, target contours were performed on the planning CT, resulting in the generation of Target_3D and Target_4D. Clinical plans, Plan_3D and Plan_4D, were designed based on these contours respectively. To explore the dosimetric variations resulting from different contours without re-optimization, Plan_3D was directly applied to Target_4D, and Plan_4D was applied to Target_3D to generate Plan_3D' and Plan_4D' respectively. Target volume, contours, dose-volume histograms (DVHs), conformity index (CI), homogeneity index (HI), maximum and mean dose to organ as risks (OARs) were compared and evaluated.

RESULTS

Mean volume differences between Target_3D and Target_4D were 2.76 cm3 (standard deviation [SD] 3.42 cm3) in the caudate lobe, 181.54 cm3 (SD 68.50 cm3) in the left hepatic lobe, and 26.08 cm3 (SD 20.52 cm3) in the right hepatic lobe. Mean and SD of CI and HI is 1.02 ± 0.04 and 0.108 ± 0.02 in Plan_3D, 1.02 ± 0.01 and 0.107 ± 0.01 in Plan_4D. There were no statistically significant differences in OAR doses between Plan_3D and Plan_3D', between Plan_4D and Plan_4D'. However, a statistically significant difference in target dose was observed between Plan_3D and Plan_3D' (P = 1.47 × 10⁻⁷) and between Plan_4D and Plan_4D' (P = 0.013). Plan_3D' meets 100% of the prescription dose covering mean 77.89% (SD 10.13%) of the Targeted_4D volume, while Plan_4D' covered mean 94.17% (SD 3.12%) of the Targeted_3D volume.

CONCLUSIONS

3D image-guided target delineation may be more likely to underestimate target volume and compromise dose coverage, suggesting that using multi-parametric 4D-MRI can provide more precise target contours and enhance target dose coverage.

Advancements in the application of ablative therapy and its combination with immunotherapy in anti-cancer therapy

Cancer is a significant health issue impacting humans. Currently, systemic therapies such as chemotherapy have significantly increased the life expectancy of cancer patients. However, some patients are unable to endure systemic treatment due to its significant adverse effects, leading to an increased focus on local therapies including radiation and ablation therapy. Ablation therapy is a precise, low-toxicity, and minimally invasive localized therapy that is increasingly acknowledged by clinicians and cancer patients. Many cancer patients have benefited from it, with some achieving full recovery. Currently, numerous studies have shown that ablation therapy is effective due to its ability to kill cancer cells efficiently and activate the body's anti-cancer immunity. It can also convert "cold cancers" into "hot cancers" and enhance the effectiveness of immunotherapy when used in combination. In this article, we categorize ablation therapy into thermal ablation, cryoablation, photodynamic therapy (PDT), irreversible electroporation (IRE), etc. Thermal ablation is further divided into Radiofrequency ablation (RFA), microwave ablation (WMA), high-frequency focused ultrasound (HIFU), photothermal therapy (PTT), magnetic heat therapy (MHT), etc. We systematically review the most recent advancements in these ablation therapies that are either currently used in clinic or are anticipated to be used in clinic. Then, we also review the latest development of various ablative therapies combined with immunotherapy, and its future development. CLINICAL RELEVANCE STATEMENT: Ablation therapy, an invasive localized treatment, offers an alternative to systemic therapies for cancer patients who cannot tolerate their adverse effects. Its ability to kill cancer cells efficiently and activate anti-cancer immunity. This article reviews recent advancements in ablation therapies, including thermal, cryoablation, PDT, and IRE, and their potential clinical applications, both standalone and in combination with immunotherapy.

Comparative analysis of clinical treatment outcomes: Breath-hold vs. free-breathing techniques in liver stereotactic body radiotherapy

INTRODUCTION

The aim of this study was to clarify the safety and efficacy of breath-hold irradiation in liver stereotactic body radiotherapy (SBRT).

METHODS

A retrospective analysis was conducted on 57 consecutive patients who received SBRT for hepatocellular carcinoma or liver metastases between 2013 and 2021. Breath-hold irradiation was implemented for patients treated after April 2020.

RESULTS

The median follow-up period for all patients was 16.4 months (IQR: 7.36-20.9). The 2-year overall survival rate was 64.4% (95% CI: 47.4-77.2), and the local control rate was 84.3% (95% CI: 69.7-92.3) for all patients. The 1-year overall survival was 80.0% (95% CI: 60.8-90.5) versus 82.0% (95% CI: 53.5-93.9) in the free-respiratory (FR) group versus the breath-hold (BH) group, respectively (P = 0.60). The 1-year local control rates were 78.1% (95% CI: 57.5-89.5) in the FR group and 95.7% (95% CI: 72.9-99.4) in the BH group, respectively (P = 0.16). Radiation-induced liver injury, defined by an escalation of ≥2 in Child-Pugh score, was observed in four patients within each group (FR 13% vs. BH 15%). There were no gastrointestinal adverse events of Grade 3 or higher.

CONCLUSION

Breath-hold irradiation can be safely administered and has demonstrated clinical potential in improving local control. Further research into dose escalation using breath-hold techniques is warranted.

EASL Clinical Practice Guidelines on the management of hepatocellular carcinoma

Liver cancer is the third leading cause of cancer-related deaths worldwide, with hepatocellular carcinoma (HCC) accounting for approximately 90% of primary liver cancers. Advances in diagnostic and therapeutic tools, along with improved understanding of their application, are transforming patient treatment. Integrating these innovations into clinical practice presents challenges and necessitates guidance. These clinical practice guidelines offer updated advice for managing patients with HCC and provide a comprehensive review of pertinent data. Key updates from the 2018 EASL guidelines include personalised surveillance based on individual risk assessment and the use of new tools, standardisation of liver imaging procedures and diagnostic criteria, use of minimally invasive surgery in complex cases together with updates on the integrated role of liver transplantation, transitions between surgical, locoregional, and systemic therapies, the role of radiation therapies, and the use of combination immunotherapies at various stages of disease. Above all, there is an absolute need for a multiparametric assessment of individual risks and benefits, considering the patient's perspective, by a multidisciplinary team encompassing various specialties.

Stereotactic body radiotherapy alone versus stereotactic body radiotherapy after incomplete transarterial therapy for hepatocellular carcinoma

INTRODUCTION

We investigated the clinical outcomes of stereotactic body radiation therapy (SBRT) alone versus SBRT after incomplete transarterial chemoembolization (TACE) for a single recurrent hepatocellular carcinoma (HCC) smaller than 5 cm.

METHODS

We retrospectively reviewed the medical records of patients who underwent SBRT for a single recurrent HCC ≤5 cm, without vascular invasion or extrahepatic metastasis. Patients were divided into the SBRT-alone group and the TACE-SBRT group. The primary outcome was the local control (LC) rate, and secondary outcomes were survivals and treatment-related toxicities. We additionally conducted a propensity score matching (PSM) analysis.

RESULTS

A total of 477 patients were available for analysis. Among them, 54 patients received SBRT without prior treatment to the target lesion (SBRT-alone group), whereas 423 patients received SBRT for viable HCC after TACE (TACE-SBRT group). The 3-year LC rates did not differ between the two groups (SBRT-alone group, 88.6% vs. TACE-SBRT group, 89.6%, P = 0.918). The 3-year rates of overall survival, out-of-field intrahepatic recurrence-free survival and recurrence-free survival were also not significantly different (P = 0.479, 0.290 and 0.273, respectively). Even after PSM, LC and survival rates at 3 years were not significantly different.

CONCLUSION

SBRT alone demonstrated comparable local control and survival outcomes to SBRT following incomplete TACE. SBRT alone may be considered an alternative treatment option for a single recurrent HCC smaller than 5 cm when curative treatments or TACE are not feasible.

Stereotactic body radiation therapy in primary liver tumor: Local control, outcomes and toxicities

Objective

Stereotactic body radiation therapy (SBRT) is a therapeutic option in the guidelines for liver primaries after standard strategies like surgery or thermoablation have failed. To assess its efficacy and safety, we reviewed all patients treated by SBRT for a hepatocellular carcinoma (HCC) over a six-year period.

Methods and materials

The study included all patients treated by SBRT for HCC between April 2015 and November 2021 in the University Cancer Institute at Toulouse-Oncopole. All patients were inoperable and not eligible for thermoablation, or after a failure. All tumor sizes were included and cirrhosis up to Child-Pugh B was accepted. Local control (LC), overall survival (OS) and progression-free survival (PFS) were estimated by the Kaplan-Meier method. Treatment response was assessed using mRECIST criteria. Toxicity was graded using CTCAE (v4.0).

Results

One hundred and nine patients with 118 lesions were treated. Half underwent prior standard treatment. Median dose was 50 Grays in five fractions for most patients. Chronic liver disease represented 90.8 % of cases with a median age of 69 years. Median tumor size was 4.0 cm. Median follow-up was 22.2 months [95 %CI: 15.1-30.4]. LC, OS and PFS at two years were 82.4 % [95 %CI: 71.3; 89.5], 73.2 % [95 %CI: 61.5; 81.8] and 35.8 % [95 %CI: 25.1; 46.7], respectively. Acute toxicities occurred in 20.2 % of patients, including 10.1 % grade 3-4 and 1.8 % grade 5. Late toxicities occurred in 5.5 % of patients including 4.6 % grade 3-4. Grade ≥ 3 toxicity was related to digestive perforation or liver failure.

Conclusion

SBRT provides good LC with an acceptable safety profile. It can be used in several settings such as salvage therapy or in combination with validated treatment. Prospective randomized trials are needed to validate SBRT as a standard alternative.

Exploring the Evolving Landscape of Stereotactic Body Radiation Therapy in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) carries significant morbidity and mortality. Management of the HCC requires a multidisciplinary approach. Surgical resection and liver transplantation are the gold standard options for the appropriate settings. Stereotactic body radiation therapy (SBRT) has emerged as a promising treatment modality in managing HCC; its use is more studied and well-established in advanced HCC (aHCC). Current clinical guidelines universally endorse SBRT as a viable alternative to radiofrequency ablation (RFA), transarterial chemoembolisation (TACE), and transarterial radioembolisation (TARE), a recommendation substantiated by literature demonstrating comparable efficacy among these modalities. In early-stage HCC, SBRT primarily manages unresectable tumours unsuitable for ablative procedures such as microwave ablation and RFA. SBRT has been incorporated as a modality to downstage tumours or as a bridge to transplant. In the case of intermediate or advanced HCC, SBRT offers excellent results either as a single modality or adjunct to other locoregional modalities such as TACE/TARE. Recent data from late-stage HCC patients illustrate the effectiveness of SBRT in achieving local tumour control while minimising damage to surrounding healthy liver tissue. It has promising local control of approximately 80-90% in managing HCC. Additional prospective data comparing the efficacy of SBRT with the first-line recommended therapies such as RFA, TACE, and surgery are essential. The standard of care for patients with advanced/metastatic disease is systemic therapy (immunotherapy/tyrosine kinase inhibitors). SBRT, in combination with immune-checkpoint inhibitors, has an immune-modulatory effect that results in a synergistic effect. Recent findings indicate that the combination of immunotherapy and SBRT in HCC is well-tolerated and exhibits synergistic effects. Further exploration of diverse immunotherapy and radiotherapy strategies is essential to identify the appropriate time for combination treatments and to optimise dose and fraction regimens. Prospective, randomised studies are imperative to establish SBRT as the primary treatment for HCC.

Primary treatments for solitary hepatocellular carcinoma ≤ 3 cm: A systematic review and network meta-analysis

Various treatment modalities are available for small solitary hepatocellular carcinoma (HCC), yet the optimal primary treatment strategy for tumors ≤ 3 cm remains unclear. This network meta-analysis investigates the comparative efficacy of various interventions on the long-term outcomes of patients with solitary HCC ≤ 3 cm. A systematic search of electronic databases from January 2000 to December 2023 was conducted to identify studies that compared at least two of the following treatments: surgical resection (SR), radiofrequency ablation (RFA), microwave ablation (MWA), and transarterial chemoembolization (TACE). Survival data were extracted, and pooled hazard ratios with 95% confidence intervals were calculated using a frequentist network meta-analysis. A total of 30 studies, comprising 2 randomized controlled trials and 28 retrospective studies, involving 8,053 patients were analyzed. Surgical resection showed the highest overall survival benefit with a p-score of 0.95, followed by RFA at 0.59, MWA at 0.23, and TACE, also at 0.23. Moreover, SR provided the most significant recurrence-free survival advantage, with a p-score of 0.95, followed by RFA at 0.31 and MWA at 0.19. Sensitivity analyses, excluding low-quality or retrospective non-matched studies, corroborated these findings. This network meta-analysis demonstrates that SR is the most effective first-line curative treatment for single HCC ≤ 3 cm, followed by RFA in patients with preserved liver function. The limited data on MWA and TACE underscore the need for further studies.

Investigate potential clinical benefits and linear energy transfer sparing utilizing proton arc therapy for hepatocellular carcinoma

PURPOSE

To investigate the potential clinical benefits and dose-averaged Linear Energy Transfer (LETd) sparing, utilizing proton arc plan for hepatocellular carcinoma (HCC) patients in comparison with Intensity Modulated Proton Therapy (IMPT).

METHODS

Ten HCC patients have been retrospectively selected. Two planning groups were created: Proton Arc plans using Monaco ver. 6 and the clinical IMPT plan. Both planning groups used the same robustness parameters. The prescription dose is 67.5 Gy (RBE) in 15 fractions of the Clinical Target Volume (CTV). Robustness evaluations were performed to ensure dose coverage. Normal Tissue Complicated Probability (NTCP) model was utilized to predict the possibility of Radiation-Induced Liver Disease (RILD) and evaluate the potential benefit of proton arc therapy. LETd calculation and evaluation were performed as well.

RESULTS

Proton arc plan has shown better dosimetric improvements of most Organ-At-Risks (OARs). More specifically, the liver mean dose has been significantly reduced from 14.7 GyE to 10.62 GyE compared to the IMPT plan. The predicted possibility of RILD has also been significantly reduced for cases with a large and deep liver target where healthy liver tissue sparing is a challenge. Additionally, proton arc therapy could increase the average LETd in the target and reduce LETd in adjacent OARs.

CONCLUSIONS

The potential clinical benefit of utilizing proton arc therapy HCC varies depending on the patient-specific geometry. With more freedom, proton arc therapy can offer a better dosimetric plan quality in the challenge cases, which might not be feasible using the current IMPT technique.

The impacts of physical factors on huge hepatocellular carcinoma treated by transarterial chemoembolization combined with radiotherapy

Aims: To assess the influence of various physical factors on the outcome of transarterial chemoembolization combined with γ-ray hypofractionated radiation therapy (TACE-γHRT) for unresectable huge (≥10 cm) hepatocellular carcinoma (UH-HCC) patients.Materials & methods: A total of 162 UH-HCC patients with different tumor locations treated with TACE-γHRT and a retrospective analysis was conducted to evaluate the impacts of selected physical parameters on clinical outcomes.Results: The selected physical factors influenced the clinical outcomes significantly. No adverse events exceeding grade 3 were observed in the enrolled patients.Conclusion: Higher P70 and marginal dose, smaller tumor size and tumor location of neither skin nor gastrointestinal tracts involved were independent predictors for better overall survival and progression free survival.

Dosimetric impact of the respiratory motion of the liver dome in stereotactic body radiotherapy for spine metastasis: A planning study

PURPOSE

This study aimed to clarify the dosimetric impact of the respiratory motion of the liver on stereotactic body radiation therapy (SBRT) for spine metastasis and examine the utility of introducing beam avoidance (beam-off at specific gantry angles).

METHODS

A total of 112 consecutive patients who underwent SBRT for spine metastasis between 2018 and 2024 were examined. Overall, 15 patients who had lesions near the liver dome were included in this study. Retrospective treatment plans were generated using computed tomography (CT) images acquired during inhalation and exhalation to evaluate the dosimetric impact of respiratory motion of the liver. The dose difference (DD) and relative value (DD%) were evaluated using the dose-volume histogram (DVH) metrics, planning target volume Dmax, D95%, spinal cord D0.035 cc, and esophagus D2.5 cc. The magnitude of the liver movements was evaluated based on differences of liver size Lave at the isocentric axial plane between the inspiratory and expiratory CT images.

RESULTS

The DD in almost all DVH metrics tended to increase when the liver moved away from the target during inhalation: For example, Mean ± $ \pm $ a standard deviation (SD) DD in PTV D95% for the treatment plan incorporating beam avoidance and those without beam avoidance was 0.5 ± $\pm$ 0.3 and 0.9 ± $ \pm $ 0.6 Gy, respectively. The spinal cord D0.035 cc for those shows 0.4 ± $ \pm $ 0.2 and 0.7 ± $ \pm $ 0.7 Gy, respectively. The treatment plans without beam avoidance also showed moderate or strong correlations between Lave and DD for almost all DVH metrics. No correlation was seen in the beam avoidance plan. The spinal cord D0.035 cc revealed approximately 1 Gy or +4% in DD when Lave was < -4 cm.

CONCLUSIONS

Respiratory motion of the liver dome can cause substantial dosimetric discrepancies in the dose delivered to the spinal cord, although the extent depends on patient variables. Dose assessment should be performed for determining the appropriate means of respiratory management, such as breath-hold. Alternatively, beam avoidance effectively mitigates the impact.

A randomised controlled trial of Standard Of Care versus RadioAblaTion in Early Stage HepatoCellular Carcinoma (SOCRATES HCC)

BACKGROUND

Therapeutic options for early-stage hepatocellular carcinoma (HCC) in individual patients can be limited by tumor and location, liver dysfunction and comorbidities. Many patients with early-stage HCC do not receive curative-intent therapies. Stereotactic ablative body radiotherapy (SABR) has emerged as an effective, non-invasive HCC treatment option, however, randomized evidence for SABR in the first line setting is lacking.

METHODS

Trans-Tasman Radiation Oncology Group (TROG) 21.07 SOCRATES-HCC is a phase II, prospective, randomised trial comparing SABR to other current standard of care therapies for patients with a solitary HCC ≤ 8 cm, ineligible for surgical resection or transplantation. The study is divided into 2 cohorts. Cohort 1 will compromise 118 patients with tumors ≤ 3 cm eligible for thermal ablation randomly assigned (1:1 ratio) to thermal ablation or SABR. Cohort 2 will comprise 100 patients with tumors > 3 cm up to 8 cm in size, or tumors ≤ 3 cm ineligible for thermal ablation, randomly assigned (1:1 ratio) to SABR or best other standard of care therapy including transarterial therapies. The primary objective is to determine whether SABR results in superior freedom from local progression (FFLP) at 2 years compared to thermal ablation in cohort 1 and compared to best standard of care therapy in cohort 2. Secondary endpoints include progression free survival, overall survival, adverse events, patient reported outcomes and health economic analyses.

DISCUSSION

The SOCRATES-HCC study will provide the first randomized, multicentre evaluation of the efficacy, safety and cost effectiveness of SABR versus other standard of care therapies in the first line treatment of unresectable, early-stage HCC. It is a broad, multicentre collaboration between hepatology, interventional radiology and radiation oncology groups around Australia, coordinated by TROG Cancer Research.

TRIAL REGISTRATION

anzctr.org.au, ACTRN12621001444875, registered 21 October 2021.

Carbon ion radiotherapy of hepatocellular carcinoma provides excellent local control: The prospective phase I PROMETHEUS trial

Background & Aims

Inoperable hepatocellular carcinoma (HCC) can be treated by stereotactic body radiotherapy. However, carbon ion radiotherapy (CIRT) is more effective for sparing non-tumorous liver. High linear energy transfer could promote therapy efficacy. Japanese and Chinese studies on hypofractionated CIRT have yielded excellent results. Because of different radiobiological models and the different etiological spectrum of HCC, applicability of these results to European cohorts and centers remains questionable. The aim of this prospective study was to assess safety and efficacy and to determine the optimal dose of CIRT with active raster scanning based on the local effect model (LEM) I.

Methods

CIRT was performed every other day in four fractions with relative biological effectiveness (RBE)-weighted fraction doses of 8.1-10.5 Gy (total doses 32.4-42.0 Gy [RBE]). Dose escalation was performed in five dose levels with at least three patients each. The primary endpoint was acute toxicity after 4 weeks.

Results

Twenty patients received CIRT (median age 74.7 years, n = 16 with liver cirrhosis, Child-Pugh scores [CP] A5 [n = 10], A6 [n = 4], B8 [n = 1], and B9 [n = 1]). Median follow up was 23 months. No dose-limiting toxicities and no toxicities exceeding grade II occurred, except one grade III gamma-glutamyltransferase elevation 12 months after CIRT, synchronous to out-of-field hepatic progression. During 12 months after CIRT, no CP elevation occurred. The highest dose level could be applied safely. No local recurrence developed during follow up. The objective response rate was 80%. Median overall survival was 30.8 months (1/2/3 years: 75%/64%/22%). Median progression-free survival was 20.9 months (1/2/3 years: 59%/43%/43%). Intrahepatic progression outside of the CIRT target volume was the most frequent pattern of progression.

Conclusions

CIRT of HCC yields excellent local control without dose-limiting toxicity.

Impact and implications

To date, safety and efficacy of carbon ion radiotherapy for hepatocellular carcinoma have only been evaluated prospectively in Japanese and Chinese studies. The optimal dose and fractionation when using the local effect model for radiotherapy planning are unknown. The results are of particular interest for European and American particle therapy centers, but also of relevance for all specialists involved in the treatment and care of patients with hepatocellular carcinoma, as we present the first prospective data on carbon ion radiotherapy in hepatocellular carcinoma outside of Asia. The excellent local control should encourage further use of carbon ion radiotherapy for hepatocellular carcinoma and design of randomized controlled trials.

Clinical Trials Registration

The study is registered at ClinicalTrials.gov (NCT01167374).

Survival Outcome Analysis of Stereotactic Body Radiotherapy and Immunotherapy (SBRT-IO) versus SBRT-Alone in Unresectable Hepatocellular Carcinoma

Introduction

While combination of stereotactic body radiotherapy (SBRT) and immunotherapy are promising, their efficacy and safety have not been compared with SBRT-alone in patients with unresectable hepatocellular carcinoma (HCC).

Methods

This retrospective study included 100 patients with nonmetastatic, unresectable HCC in two hospitals. Eligible patients had tumor nodules ≤3 and Child-Pugh liver function score of A5 to B7. Seventy patients received SBRT-alone, and 30 patients underwent combined SBRT and immunotherapy (SBRT-IO). Overall survival (OS), time to progression (TTP), overall response rate (ORR), and toxicity were analyzed. We adjusted for the potential confounding factors using propensity score matching.

Results

The median tumor size was 7.3 cm (range, 2.6-18 cm). Twenty-five (25%) of patients had vascular invasion. Before propensity score matching, the 1-year and 3-year OS rate was 89.9% and 59.8% in the SBRT-IO group and 75.7% and 42.3% in SBRT-alone group (p = 0.039). After propensity score matching (1:2), 25 and 50 patients were selected from the SBRT-IO and SBRT-alone group. The 1-year and 3-year OS was 92.0% and 63.9% in the SBRT-IO group versus 74.0% and 43.3% in the SBRT-alone group (p = 0.034). The 1-year and 3-year TTP was better in SBRT-IO group (1-year: 68.9% vs. 58.9% and 3-year: 61.3% vs. 32.5%, p = 0.057). The ORR of 88% (complete response [CR]: 56%, partial response [PR]: 22%) in SBRT-IO arm was significantly better than 50% (CR: 20%, PR: 30%) in the SBRT-alone arm (p = 0.006). Three patients (12%) developed ≥grade 3 immune-related treatment adverse events (n = 2 hepatitis, n = 1 dermatitis) leading to permanent treatment discontinuation.

Conclusion

Adding immunotherapy to SBRT resulted in better survival with manageable toxicities. Prospective randomized trial is warranted.

Biochemical Safety of SBRT to Multiple Intrahepatic Lesions for Hepatocellular Carcinoma

Background

We aim to better characterize stereotactic body radiation therapy (SBRT)-related hepatic biochemical toxicity in patients with multiple intrahepatic lesions from hepatocellular carcinoma (HCC).

Methods

We conducted a retrospective analysis of patients with HCC who underwent SBRT for 2 or more synchronous or metachronous liver lesions. We collected patient characteristics and dosimetric data (mean liver dose [MLD], cumulative effective volume [Veff], cumulative volume of liver receiving 15 Gy [V15Gy], and cumulative planning target volume [PTV]) along with liver-related toxicity (measured by albumin-bilirubin [ALBI] and Child-Pugh [CP] scores). A linear mixed-effects model was used to assess the effect of multi-target SBRT on changes in ALBI.

Results

There were 25 patients and 56 lesions with median follow-up of 29 months. Eleven patients had synchronous lesions, and 14 had recurrent lesions treated with separate SBRT courses. Among those receiving multiple SBRT courses, there were 7 lesions with overlap of V15Gy (median V15Gy overlap: 35 mL, range: 0.5-388 mL). There was no association between cumulative MLD, Veff, V15Gy, or PTV and change in ALBI. Four of 25 patients experienced non-classic radiation-induced liver disease (RILD), due to an increase of CP score by ≥2 points 3 to 6 months after SBRT. Sixteen of 25 patients experienced an increase in ALBI grade by 1 or more points 3 to 6 months after SBRT. Comparing the groups that received SBRT in a single course versus multiple courses revealed no statistically significant differences in liver toxicity.

Conclusion

Liver SBRT for multiple lesions in a single or in separate courses is feasible and with acceptable risk of hepatotoxicity. Prospective studies with a larger cohort are needed to better characterize safety in this population.

Do We Have a Winner? Advocating for SBRT in HCC Management

•Stereotactic body radiotherapy (SBRT) is a safe and effective locoregional therapy for inoperable patients with HCC.•SBRT compares favorably with other local therapies in terms of local control, survival, morbidity, and cost-effectiveness.•SBRT should be considered and discussed in multidisciplinary management of appropriate HCC patients.•Advances in SBRT and novel combinations with systemic therapy may further widen the therapeutic index in HCC.

Stereotactic Body Radiation Therapy for Hepatocellular Carcinoma: Meta-Analysis and International Stereotactic Radiosurgery Society Practice Guidelines

This systematic review and meta-analysis reports on outcomes and hepatic toxicity rates after stereotactic body radiation therapy (SBRT) for liver-confined hepatocellular carcinoma (HCC) and presents consensus guidelines regarding appropriate patient management. Using the Preferred Reporting Items for Systemic Review and Meta-Analyses guidelines, a systematic review was performed from articles reporting outcomes at ≥5 years published before October 2022 from the Embase, MEDLINE, Cochrane, and Scopus databases with the following search terms: ("stereotactic body radiotherapy" OR "SBRT" OR "SABR" OR "stereotactic ablative radiotherapy") AND ("hepatocellular carcinoma" OR "HCC"). An aggregated data meta-analysis was conducted to assess overall survival (OS) and local control (LC) using weighted random effects models. In addition, individual patient data analyses incorporating data from 6 institutions were conducted as their own subgroup analyses. Seventeen observational studies, comprising 1889 patients with HCC treated with ≤9 SBRT fractions, between 2003 and 2019, were included in the aggregated data meta-analysis. The 3- and 5-year OS rates after SBRT were 57% (95% confidence interval [CI], 47%-66%) and 40% (95% CI, 29%-51%), respectively. The 3- and 5-year LC rates after SBRT were 84% (95% CI, 77%-90%) and 82% (95% CI, 74%-88%), respectively. Tumor size was the only prognostic factor for LC. Tumor size and region were significantly associated with OS. Five-year LC and OS rates of 79% (95% CI, 0.74-0.84) and 25% (95% CI, 0.20-0.30), respectively, were observed in the individual patient data analyses. Factors prognostic for improved OS were tumor size <3 cm, Eastern region, Child-Pugh score ≤B7, and the Barcelona Clinic Liver Cancer stage of 0 and A. The incidence of severe hepatic toxicity varied according to the criteria applied. SBRT is an effective treatment modality for patients with HCC with mature follow-up. Clinical practice guidelines were developed on behalf of the International Stereotactic Radiosurgery Society (ISRS).

SBRT for Liver Tumors: What the Interventional Radiologist Needs to Know

This review summarizes the clinical evidence supporting the utilization of stereotactic body radiotherapy (SBRT) for liver tumors, including hepatocellular carcinoma, liver metastases, and cholangiocarcinoma. Emerging prospective evidence has demonstrated the benefit and low rates of toxicity across a broad range of clinical contexts. We provide an introduction for the interventional radiologist, with a discussion of underlying themes such as tumor dose-response, mitigation of liver toxicity, and the technical considerations relevant to performing liver SBRT. Ultimately, we recommend that SBRT should be routinely included in the armamentarium of locoregional therapies for liver malignancies, alongside those liver-directed therapies offered by interventional radiology.

Efficacy of Transarterial Chemoembolization (TACE) for Early-Stage Hepatocellular Carcinoma

Backgound and Objectives: The treatments of choice for patients with early-stage hepatocellular carcinoma (HCC) are surgical resection, local ablation therapy, and liver transplantation; however, transarterial chemoembolization (TACE) is commonly performed due to variations among patients and liver diseases. This study aimed to assess the efficacy of TACE in patients with early-stage HCC. Materials and Methods: A retrospective analysis was performed of all TACE procedures performed at Kyung Hee University Hospital at Gangdong over a 15-year period (July 2006 to November 2021). The study included a total of 97 eligible patients with early-stage HCC ≤ 5 cm initially treated with TACE. The mean participant age was 63.47 ± 11.02 years; 69 were men (71.1%). The number of Child-Pugh class A patients was the highest (74 patients [76.3%]), followed by Child-Pugh class B (19 patients [19.6%]) and Child-Pugh class C (4 patients [4.12%]). Results: A complete response was achieved in 84 (86.6%) patients after the first TACE procedure, with 1-, 2-, and 3-year survival rates of 91.8%, 87.3%, and 75.4%, respectively. In the multivariate analysis, the patients with a low initial alpha-fetoprotein (AFP) ≤ 20 ng/mL (p = 0.02) and a complete response after the first TACE (p = 0.03) were associated with favorable overall survival. Conclusions: TACE can be used to treat patients with early-stage HCC who are unsuitable for ablation or surgery. If patients are well selected, TACE may be an alternative treatment for patients with low AFP levels who respond well to the initial TACE procedure.

Combination treatment of HCC with SBRT and immune checkpoint inhibition

The treatment of unresectable or metastatic HCC has been significantly advanced in recent years by developments in both radiotherapy and systemic cancer therapies. Independently, both Stereotactic Ablative Body Radiotherapy (SBRT) and Immune Checkpoint Inhibitors (ICIs) are licensed for the treatment of these tumours. Building on the successes seen in other solid tumours, there is significant interest in exploring combination treatments. In this review article we briefly present the evidence base for the use of these treatments in patients with HCC. With reference to our current understanding of the immuno-oncology and radiobiology of HCCs, we demonstrate why combining these two modalities is of interest. Finally, we discuss the clinical trials that are currently underway or planned and the direction that future research may take.

Definitive Stereotactic Body Radiation Therapy in Early-Stage Solitary Hepatocellular Carcinoma: An Australian Multi-Institutional Review of Outcomes

AIMS

Standard curative options for early-stage, solitary hepatocellular carcinoma (HCC) are often unsuitable due to liver dysfunction, comorbidities and/or tumour location. Stereotactic body radiation therapy (SBRT) has shown high rates of local control in HCC; however, limited data exist in the treatment-naïve, curative-intent setting. We report the outcomes of patients with solitary early-stage HCC treated with SBRT as first-line curative-intent therapy.

MATERIALS AND METHODS

A multi-institutional retrospective study of treatment-naïve patients with Barcelona Clinic Liver Cancer stage 0/A, solitary ≤5 cm HCC, Child-Pugh score (CPS) A liver function who underwent SBRT between 2010 and 2019 as definitive therapy. The primary end point was freedom from local progression. Secondary end points were progression-free survival, overall survival, rate of treatment-related clinical toxicities and change in CPS >1.

RESULTS

In total, 68 patients were evaluated, with a median follow-up of 20 months (range 3-58). The median age was 68 years (range 50-86); 54 (79%) were men, 62 (91%) had cirrhosis and 50 (74%) were Eastern Cooperative Oncology Group 0. The median HCC diameter was 2.5 cm (range 1.3-5) and the median prescription biologically effective dose with a tumour a/b ratio of 10 Gy (BED10) was 93 Gy (interquartile range 72-100 Gy). Two-year freedom from local progression, progression-free survival and overall survival were 94.3% (95% confidence interval 86.6-100%), 59.5% (95% confidence interval 46.3-76.4%) and 88% (95% confidence interval 79.2-97.6%), respectively. Nine patients (13.2%) experienced grade ≥2 treatment-related clinical toxicities. A rise >1 in CPS was observed in six cirrhotic patients (9.6%).

CONCLUSION

SBRT is an effective and well-tolerated option to consider in patients with solitary, early-stage HCC. Prospective, randomised comparative studies are warranted to further refine its role as a first-line curative-intent therapy.

A prospective registry study of stereotactic magnetic resonance guided radiotherapy (MRgRT) for primary liver tumors

BACKGROUND AND PURPOSE

Stereotactic body radiation therapy (SBRT) has demonstrated safe and effective results for primary liver tumors. Magnetic Resonance guided Radiotherapy (MRgRT) is an innovative radiotherapy modality for abdominal tumors. The aim of this study is to report on acute and late toxicities and initial oncological results for primary liver tumors treated with MRgRT.

MATERIALS AND METHODS

We prospectively included in our cohort all patients treated by MRgRT for a primary liver tumor at the Montpellier Cancer Institute. The primary endpoint was acute and late toxicities assessed according to CTCAE v 5.0. The mean prescribed dose was 50 Gy in 5 fractions.

RESULTS

Between October 2019 and April 2022, MRgRT treated 56 patients for 72 primary liver lesions. No acute or late toxicities of CTCAE grade greater than 2 attributable to radiotherapy were noted during follow-up. No cases of radiation-induced liver disease (RILD), either classical or non-classical, occurred. After a median follow-up of 13.2 months (95% CI [8.8; 15.7]), overall survival was 85.1% (95% CI: [70.8; 92.7]) at 1 year and 74.2% at 18 months (95% CI [52.6; 87.0]). Local control was 98.1% (95% CI: [87.4; 99.7]) and 94.7% (95% CI: [79.5; 98.7]) at 12 and 18 months, respectively. Among the HCC subgroup, no local recurrences were observed.

CONCLUSION

MRgRT for primary liver tumors is safe without severe adverse events and reach excellent local control. Numerous studies are underway to better assess the value of MRI guidance and adaptive process in these indications.

Clinical Implication of E2F Transcription Factor 1 in Hepatocellular Carcinoma Tissues

Background: To date, the clinical management of advanced hepatocellular carcinoma (HCC) patients remains challenging and the mechanisms of E2F transcription factor 1 (E2F1) underlying HCC are obscure. Materials and Methods: Our study integrated datasets mined from several public databases to comprehensively understand the deregulated expression status of E2F1. Tissue microarrays and immunohistochemistry staining was used to validate E2F1 expression level. The prognostic value of E2F1 was assessed. In-depth subgroup analyses were implemented to compare the differentially expressed levels of E2F1 in HCC patients with various tumor stages. Functional enrichments were used to address the predominant targets of E2F1 and shedding light on their potential roles in HCC. Results: We confirmed the elevated expression of E2F1 in HCC. Subgroup analyses indicated that elevated E2F1 level was independent of various stages in HCC. E2F1 possessed moderate discriminatory capability in differentiating HCC patients from non-HCC controls. Elevated E2F1 correlated with Asian race, tumor classification, neoplasm histologic grade, eastern cancer oncology group, and plasma AFP levels. Furthermore, high E2F1 correlated with poor survival condition and pooled HR signified E2F1 as a risk factor for HCC. Enrichment analysis of differentially expressed genes, coexpressed genes, and putative targets of E2F1 emphasized the importance of cell cycle pathway, where CCNE1 and CCNA2 served as hub genes. Conclusions: We confirmed the upregulation of E2F1 and explored the prognostic value of E2F1 in HCC patients. Two putative targeted genes (CCNE1 and CCNA2) of E2F1 were identified for their potential roles in regulating cell cycle and promote antiapoptotic activity in HCC patients.

The Current Evidence of Intensity-Modulated Radiotherapy for Hepatocellular Carcinoma: A Systematic Review and Meta-Analysis

Intensity-modulated radiotherapy (IMRT), an advanced RT technique, is a considerable treatment option for hepatocellular carcinoma (HCC). However, the distinguishing features of IMRT for HCC have not yet been clearly defined. A systematic review was performed according to the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. The PubMed/MedLine, Embase, Cochrane Library, Web of Science, and KoreaMed were used to screen eligible studies focusing on treatment outcomes after IMRT for HCC until 18 April 2023. A total of 1755 HCC patients receiving IMRT among 29 studies from 2009 to 2023 were selected for the meta-analysis. The median proportion of Barcelona Clinic Liver Cancer stage C was 100% (range: 38-100%). Nineteen studies used combined treatment. Pooled rates of response and 1-year local control were 58% (95% confidence interval [CI], 50-65%) and 84% (95% CI, 70-94%), respectively. The median overall survival (OS) was 13 months (range: 5-45 months), and pooled 1- and 3-year OS rates were 59% (95% CI, 52-66%), and 23% (95% CI, 14-33%), respectively. Pooled rates of classic radiation-induced liver disease (RILD), nonclassic RILD, and hepatic toxicity ≥ grade 3 were 2%, 4%, and 4%, respectively. Although most patients had advanced-stage HCC and combined treatment was commonly used, IMRT for HCC showed similar survival to existing RT modalities and relatively low severe toxicity.

Advances in radiotherapy and immunity in hepatocellular carcinoma

Primary liver cancer is one of the most common malignant tumours worldwide; it caused approximately 830,000 deaths in 2020. Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer, accounting for over 80% of all cases. Various methods, including surgery, chemotherapy, radiotherapy, and radiofrequency ablation, have been widely used in the treatment of HCC. With the advancement of technology, radiotherapy has become increasingly important in the comprehensive treatment of HCC. However, due to the insufficient sensitivity of tumour cells to radiation, there are still multiple limitation in clinical application of radiotherapy. In recent years, the role of immunotherapy in cancer has been increasingly revealed, and more researchers have turned their attention to the combined application of immunotherapy and radiotherapy in the hope of achieving better treatment outcomes. This article reviews the progress on radiation therapy in HCC and the current status of its combined application with immunotherapy, and discusses the prospects and value of radioimmunotherapy in HCC.

Local Treatment of Hepatocellular Carcinoma with Oligometastases: A Systematic Review and Meta-Analysis

Although recent studies have shown favorable results after local treatment for oligometastases, the clinical decision of applying local treatment for oligometastatic hepatocellular carcinoma (HCC) remains controversial. This meta-analysis aimed to investigate the benefits of local treatment for HCC oligometastases. Pubmed, Embase, Medline, and the Cochrane library were searched for studies until 1 May 2022. Clinical studies involving at least five cases of HCC oligometsatases treated with local modalities were included. The primary endpoint was overall survival (OS). The benefit of local treatment was assessed as the pooled odds ratio (OR) among comparative series, and the pooled OS percentile was calculated from all studies including patients treated with local treatment. Complications of grade ≥ 3 were assessed subjectively. A total of 10 studies involving 527 patients were included. Radiotherapy and radiofrequency ablation (RFA) were mainly performed (six and five studies) as local modalities treating oligometastases. Pooled OR of comparative series favored the use of local treatment (4.664, 95% confidence interval [CI]: 2.595-8.380, p < 0.001, I²: ~0.0%). Including all cohorts with patients who underwent local treatment, pooled rates of 1-year OS were 71.8% (95% CI: 59.0-81.9; I² = 81.5%), and pooled 2-year OS were 43.3% (95% CI: 29.1-59.6; I² = 85.4%). Except for temporal or pre-existing toxicities, grade ≤ 3 complications were reported less than 10% in most studies, although common toxicities include pneumothorax and hematologic deficiency after RFA and radiotherapy, respectively. Grade 5 toxicity has not yet been reported. This systematic review supports the application of local treatment for treating HCC oligometastases.

Effects of stereotactic body radiotherapy for clinical outcomes of patients with liver metastasis and hepatocellular carcinoma: A retrospective study

This retrospective clinical study described the treatment efficacy and safety of stereotactic body radiotherapy (SBRT) for patients of hepatocellular carcinoma (HCC) and liver metastasis tumors. The therapeutic effect and prognosis of patients with liver cancer treated with stereotactic body radiation therapy (SBRT) at the Fudan University Shanghai Cancer Center (Shanghai, China) between July 2011 and December 2020 were retrospectively analyzed. Overall survival (OS), local control (LC) rates and progression-free survival (PFS) were evaluated using Kaplan-Meier analysis and the log-rank test. Local progression was defined as tumor growth after SBRT on dynamic computed tomography follow-up. Treatment-related toxicities were assessed according to the Common Terminology Criteria for Adverse Events version 4. A total of 36 patients with liver cancer were enrolled in the present study. The prescribed dosages (14 Gy in 3 fractions or 16 Gy in 3 fractions) were applied for SBRT treatments. The median follow-up time was 21.4 months. The median OS time was 20.4 [95% confidence interval (CI): 6.6-34.2] months, and the 2-year OS rates for the total population, HCC group and liver metastasis group were 47.5, 73.3 and 34.2%, respectively. The median PFS time was 17.3 (95% CI: 11.8-22.8) months and the 2-year PFS rates for the total population, HCC group and liver metastasis group were 36.3, 44.0 and 31.4%, respectively. The 2-year LC rates for the total population, HCC group and liver metastasis group were 83.4, 85.7 and 81.6%, respectively. The most common grade IV toxicity for the HCC group was liver function impairment (15.4%), followed by thrombocytopenia (7.7%). There were no grade III/IV radiation pneumonia or digestive discomfort. The present study aimed to explore a safe, effective and non-invasive treatment method for liver tumors. At the same time, the innovation of the present study is to find a safe and effective prescription dose of SBRT in the absence of consensus on guidelines.

Clinical outcomes of patients with unresectable primary liver cancer treated with MR-guided stereotactic body radiation Therapy: A Six-Year experience

Purpose

Magnetic resonance-guided stereotactic body radiation therapy (MRgSBRT) with optional online adaptation has shown promise in delivering ablative doses to unresectable primary liver cancer. However, there remain limited data on the indications for online adaptation as well as dosimetric and longer-term clinical outcomes following MRgSBRT.

Methods and Materials

Patients with unresectable hepatocellular carcinoma (HCC), cholangiocarcinoma (CCA), and combined biphenotypic hepatocellular-cholangiocarcinoma (cHCC-CCA) who completed MRgSBRT to 50 Gy in 5 fractions between June of 2015 and December of 2021 were analyzed. The necessity of adaptive techniques was evaluated. The cumulative incidence of local progression was evaluated and survival and competing risk analyses were performed.

Results

Ninety-nine analyzable patients completed MRgSBRT during the study period and 54 % had planning target volumes (PTVs) within 1 cm of the duodenum, small bowel, or stomach at the time of simulation. Online adaptive RT was used in 53 % of patients to correct organ-at-risk constraint violation and/or to improve target coverage. In patients who underwent adaptive RT planning, online replanning resulted in superior target coverage when compared to projected, non-adaptive plans (median coverage ≥ 95 % at 47.5 Gy: 91 % [IQR: 82-96] before adaptation vs 95 % [IQR: 87-99] after adaptation, p < 0.01). The median follow-up for surviving patients was 34.2 months for patients with HCC and 10.1 months for patients with CCA/cHCC-CCA. For all patients, the 2-year cumulative incidence of local progression was 9.8 % (95 % CI: 1.5-18 %) for patients with HCC and 9.0 % (95 % CI: 0.1-18) for patients with CCA/cHCC-CCA. Grade 3 through 5 acute and late clinical gastrointestinal toxicities were observed in < 10 % of the patients.

Conclusions

MRgSBRT, with the option for online adaptive planning when merited, allows delivery of ablative doses to primary liver tumors with excellent local control with acceptable toxicities. Additional studies evaluating the efficacy and safety of MRgSBRT in the treatment of primary liver cancer are warranted.

Response evaluation of hepatocellular carcinoma treated with stereotactic body radiation therapy: magnetic resonance imaging findings

PURPOSE

To summarize the magnetic resonance imaging manifestations of hepatocellular carcinoma (HCC) with and without progression after stereotactic body radiation therapy (SBRT) and evaluate the treatment effect using the modified Liver Reporting and Data System (LI-RADS).

METHODS

Between January 2015 and December 2020, 102 patients with SBRT-treated HCC were included. Tumor size, signal intensity, and enhancement patterns at each follow-up period were analyzed. Three different patterns of enhancement: APHE and wash-out, non-enhancement, and delayed enhancement. For modified LI-RADS, delayed enhancement with no size increase were considered to be a "treatment-specific expected enhancement pattern" for LR-TR non-viable.

RESULTS

Patients were divided into two groups: without (n = 96) and with local progression (n = 6). Among patients without local progression, APHE and wash-out pattern demonstrated conversion to the delayed enhancement (71.9%) and non-enhancement (20.8%) patterns, with decreased signal intensity on T1WI(92.9%) and DWI(99%), increased signal intensity on T1WI (99%), and decreased size. The signal intensity and enhancement patterns stabilized after 6-9 months. Six cases with progression exhibited tumor growth, APHE and wash-out, and increased signal intensity on T2WI/DWI. Based on the modified LI-RADS criteria, 74% and 95% showed LR-TR-nonviable in 3 and 12 months post-SBRT, respectively.

CONCLUSIONS

After SBRT, the signal intensity and enhancement patterns of HCCs showed a temporal evolution. Tumor growth, APHE and wash-out, and increased signal intensity on T2WI/DWI indicates tumor progression. Modified LI-RADS criteria showed good performance in evaluating nonviable lesions after SBRT.

Non-classic radiation-induced liver disease after intensity-modulated radiotherapy for Child-Pugh grade B patients with locally advanced hepatocellular carcinoma

BACKGROUND

The incidence of classic radiation-induced liver disease (cRILD) has been significantly reduced. However, non-classic radiation-induced liver disease (ncRILD) remains a major concern following radiotherapy in patients with hepatocellular carcinoma (HCC). This study evaluated the incidence of ncRILD following intensity-modulated radiotherapy (IMRT) for Child-Pugh grade B (CP-B) patients with locally advanced HCC and established a nomogram for predicting ncRILD probability.

METHODS

Seventy-five CP-B patients with locally advanced HCC treated with IMRT between September 2014 and July 2021 were included. The max tumor size was 8.39 cm ± 5.06, and the median prescribed dose was 53.24 Gy ± 7.26. Treatment-related hepatotoxicity was evaluated within three months of completing IMRT. A nomogram model was formulated to predict the probability of ncRILD, using univariate and multivariate analysis.

RESULTS

Among CP-B patients with locally advanced HCC, ncRILD occurred in 17 (22.7%) patients. Two patients (2.7%) exhibited a transaminase elevation of ≥ G3, fourteen (18.7%) exhibited a Child-Pugh score increase of ≥ 2, and one (1.3%) demonstrated both a transaminase elevation of ≥ G3 and a Child-Pugh score increase of ≥ 2. No cRILD cases were observed. A mean dose to the normal liver of ≥ 15.1 Gy was used as the cutoff for ncRILD. Multivariate analysis revealed that the prothrombin time before IMRT, tumour number, and mean dose to the normal liver were independent risk factors for ncRILD. The nomogram established on the basis of these risk factors displayed exceptional predictive performance (AUC = 0.800, 95% CI 0.674-0.926).

CONCLUSIONS

The incidence of ncRILD following IMRT for CP-B patients with locally advanced HCC was acceptable. A nomogram based on prothrombin time before IMRT, tumour number, and mean dose to the normal liver accurately predicted the probability of ncRILD in these patients.

Clinical consensus statement: Establishing the roles of locoregional and systemic therapies for the treatment of intermediate-stage hepatocellular carcinoma in Canada

BACKGROUND

Hepatocellular carcinoma (HCC) a leading cause of cancer mortality worldwide and approximately one-third of patients present with intermediate-stage disease. The treatment landscape of intermediate-stage HCC is rapidly evolving due to developments in local, locoregional and systemic therapies. Treatment recommendations focused on this heterogenous disease stage and that take into account the Canadian reality are lacking. To address this gap, a pan-Canadian group of experts in hepatology, transplant, surgery, radiation therapy, nuclear medicine, interventional radiology, and medical oncology came together to develop consensus recommendations on management of intermediate-stage HCC relevant to the Canadian context.

METHODS

A modified Delphi framework was used to develop consensus statements with strengths of recommendation and supporting levels of evidence graded using the AHA/ACC classification system. Tentative consensus statements were drafted based on a systematic search and expert input in a series of iterative feedback cycles and were then circulated via online survey to assess the level of agreement.

RESULTS & CONCLUSION

The pre-defined ratification threshold of 80 % agreement was reached for all statements in the areas of multidisciplinary treatment (n = 4), intra-arterial therapy (n = 14), biologics (n = 5), radiation therapy (n = 3), surgical resection and transplantation (n = 7), and percutaneous ablative therapy (n = 4). These generally reflected an expansion in treatment options due to developments in previously established or emergent techniques, introduction of new and more active therapies and increased therapeutic flexibility. These developments have allowed for greater treatment tailoring and personalization as well as a paradigm shift toward strategies with curative intent in a wider range of disease settings.

Early complete tumor response as a survival predictor in hepatocellular carcinoma patients receiving stereotactic body radiation therapy

Background and Purpose

To evaluate the different response patterns after Stereotactic Body Radiation Therapy (SBRT) and their predictive value in local control and progression of hepatocellular carcinoma (HCC).

Materials and methods

Seventy-two HCC patients who were treated with SBRT during 2015-2020 were included in this retrospective study. The assessment was made using MRI, CT, and PET-CT. Local and systemic responses were determined according to modified Response Evaluation Criteria in Solid Tumors (mRECIST) criteria during follow up. Patients were categorized as early responders (complete response during 6 months after radiotherapy) or non-early responders (the rest of the patients). Prognostic factors were determined using multivariate logistic models.

Results

The median follow-up was 24.0 months (range, 7.7-74.5 months). We found that 84.7%（61/72) of patients achieved a complete response. Early responses occurred in 45 patients (45/72, 62.5%), and they had 1-, 2-, and 5- year intrahepatic outfield-free survival (OutFFS) rates of 86.2%, 80.3%, and 76.3% vs. 55.3%, 44.7%, and 33.5% in non-early responses patients, whereas the 1-, 2-, and 5- year distant metastasis-free survival (DMFS) were 95.5%, 84.5% and 79.5% and 74.1%, 56.2% and 56.2%, respectively. The 1-, 2-, and 5-year overall survival (OS) were 97.7%, 92.1%, 79.1%, and 85.2%, 53.8%, and 40.3%, respectively. Multivariate analysis revealed that early tumor response was an independent predictor of OutFFS, DMFS, and OS.

Conclusions

Early complete tumor response within 6 months after radiotherapy predicted better intrahepatic outfield-free survival, distant metastasis-free survival, and overall survival outcomes. Confirmation is warranted for early response on SBRT to guide decision making.

Refining stereotactic body radiation therapy as a bridge to transplantation for hepatocellular carcinoma: An institutional experience

BACKGROUND

Stereotactic body radiotherapy (SBRT) has been established as a safe and effective treatment for hepatocellular carcinoma (HCC). Currently, there are no consensus guidelines to advise optimal patient selection and radiotherapy planning parameters to minimise the risk of surgical and medical complications after liver transplant (LT) in patients who have had prior SBRT for HCC, whilst optimising treatment benefit.

METHODS

We performed a retrospective analysis of all adult patients who received liver SBRT as a bridge to LT at a tertiary institution between 2017 and 2019.

RESULTS

Nine patients received SBRT as bridging therapy to LT. HCC location varied from peripheral to central/hilar regions and HCC diameter was 13-54 mm. Median time between SBRT and LT was 141 days (range 27-461 days). Median operating time was 360 min (range 270-480 min). Four patients (44%) had visible SBRT reaction or fibrosis at the time of LT. SBRT reaction resulted in clinical impact in one patient (11%) only, where vascular clamping of the IVC was required for 10 min.

CONCLUSION

SBRT is a safe and effective treatment for HCC enabling patients to remain within LT criteria, even for lesions not amenable to other more conventional bridging therapies. We describe a preliminary decision pathway to guide the optimal use of SBRT as a bridge to LT developed in our institution.

Stereotactic Body Radiotherapy for Hepatocellular Carcinoma: A Brief Overview

Stereotactic body radiotherapy (SBRT), a type of external beam radiotherapy, yields local control of hepatocellular carcinoma (HCC) at rates as high as 90%. SBRT has been recognized as an alternative therapy for patients for whom standard modalities such as surgery (resection or transplantation) or ablation are deemed unsuitable. SBRT has the potential to improve the prognosis of HCC, as it can be used as an adjunct to other treatment modalities. The assessment of post-SBRT images of the treated tumor and surrounding normal liver tissue requires special attention. Future research is warranted to determine how best to use SBRT versus other therapies and how to combine them.

Predictive Model of Liver Toxicity to Aid the Personalized Selection of Proton Versus Photon Therapy in Hepatocellular Carcinoma

PURPOSE

Our objective was to develop an externally validated model for predicting liver toxicity after radiation therapy in patients with hepatocellular carcinoma (HCC) that can integrate both photon and proton dose distributions with patient-specific characteristics.

METHODS AND MATERIALS

Training data consisted of all patients with HCC treated between 2008 and 2019 at our institution (n = 117, 60%/40% photon/proton). We developed a shallow convolutional neural network (CNN) to predict posttreatment liver dysfunction from the differential dose-volume histogram (DVH) and baseline liver metrics. To reduce bias and improve robustness, we used ensemble learning (CNNE). After a preregistered study analysis plan, we evaluated stability using internal bootstrap resampling and generalizability using a data set from a different institution (n = 88). Finally, we implemented a class activation map method to characterize the critical DVH subregions and benchmarked the model against logistic regression and XGBoost. The models were evaluated using the area under the receiver operating characteristic curve and area under the precision-recall curve.

RESULTS

The CNNE model showed similar internal performance and robustness compared with the benchmarks. CNNE exceeded the benchmark models in external validation, with an area under the receiver operating characteristic curve of 0.78 versus 0.55 to 0.70, and an area under the precision-recall curve of 0.6 versus 0.43 to 0.52. The model showed improved predictive power in the photon group, excellent specificity in both modalities, and high sensitivity in the photon high-risk group. Models built solely on DVHs confirm outperformance of the CNNE and indicate that the proposed structure efficiently abstracts features from both proton and photon dose distributions. The activation map method demonstrates the importance of the low-dose bath and its interaction with low liver function at baseline.

CONCLUSIONS

We developed and externally validated a patient-specific prediction model for hepatic toxicity based on the entire DVH and clinical factors that can integrate both photon and proton therapy cohorts. This model complements the new American Society for Radiation Oncology clinical practice guidelines and could support value-driven integration of proton therapy into the management of HCC.

Stereotactic Radiotherapy after Incomplete Transarterial (Chemo-) Embolization (TAE\TACE) versus Exclusive TAE or TACE for Treatment of Inoperable HCC: A Phase III Trial (NCT02323360)

Background: Hepatocellular carcinoma (HCC) is the most frequent liver malignancy and a leading cause of cancer death in the world. In unresectable HCC patients, transcatheter arterial (chemo-) embolization (TAE/TACE) has shown a disease response in 15-55% of cases. Though multiple TAE/TACE courses can be administered in principle, Stereotactic Body Radiotherapy (SBRT) has emerged as an alternative option in the case of local relapse following multiple TAE/TACE courses. Methods: This is a single-center, prospective, randomized, controlled, parallel-group superiority trial of SBRT versus standard TAE/TACE for the curative treatment of the intermediate stage of HCC after an incomplete response following TAE/TACE (NCT02323360). The primary endpoint is 1-year local control (LC): 18 events were needed to assess a 45% difference (HR: 0.18) in favor of SBRT. The secondary endpoints are 1-year Progression-Free Survival (PFS), Distant Recurrence-Free Survival (DRFS), Overall Survival (OS) and the incidence of acute and late complications. Results: At the time of the final analysis, 40 patients were enrolled, 19 (49%) in the TAE/TACE arm and 21 (51%) in the SBRT arm. The trial was prematurely closed due to slow accrual. The 1- and 2-year LC rates were 57% and 36%. The use of SBRT resulted in superior LC as compared to TAE/TACE rechallenge (median not reached versus 8 months, p = 0.0002). PFS was 29% and 16% at 1 and 2 years, respectively. OS was 86% and 62% at 1 year and 2 years, respectively. In the TAE arm, PFS was 13% and 6% at 1 and 2 years, respectively. In the SBRT arm, at 1 and 2 years, PFS was 37% and 21%, respectively. OS at 1 and 2 years was 75% and 64% in the SBRT arm and 95% and 57% in the TACE arm, respectively. No grade >3 toxicity was recorded. Conclusions: SBRT is an effective treatment option in patients affected by inoperable HCC experiencing an incomplete response following ≥1 cycle of TAE/TAC.

Significant muscle loss after stereotactic body radiotherapy predicts worse survival in patients with hepatocellular carcinoma

The relationship between sarcopenia and treatment outcomes, especially in patients with hepatocellular carcinoma (HCC) undergoing stereotactic body radiotherapy (SBRT) has not been well-explored. This study aimed to investigate the effects of sarcopenia on the survival and toxicity after SBRT in patients with HCC. We included 137 patients with HCC treated with SBRT between 2008 and 2018. Sarcopenia was defined as a skeletal muscle index (SMI) of < 49 cm²/m² for men and < 31 cm²/m² for women using computed tomography images at the mid-level of the third lumbar vertebra. The SMI change was presented as the change per 90 days. The Kaplan-Meier method was used for survival estimation, and the Cox regression was used to determine prognosticators. Sarcopenia was present in 67 of 137 eligible patients. With the median follow-up of 14.1 months and 32.7 months in the entire cohort and in those alive, respectively, patients with pre-SBRT sarcopenia or SMI loss ≥ 7% after SBRT had worse overall survival than their counterparts. Significant survival predictors on multivariate analysis were SMI loss ≥ 7% after SBRT [hazard ratio (HR): 1.96, p = 0.013], presence of extrahepatic metastasis (HR: 3.47, p < 0.001), neutrophil-to-lymphocyte ratio (HR: 1.79, p = 0.027), and multiple tumors (HR: 2.19, p = 0.003). Separate Cox models according to the absence and presence of pre-SBRT sarcopenia showed that SMI loss ≥ 7% remained a significant survival predictor in patients with sarcopenia (HR: 3.06, p = 0.017) compared with those without sarcopenia. SMI loss ≥ 7% is also a predictor of the Child-Pugh score increase by ≥ 2 points after SBRT. SMI loss ≥ 7% after SBRT is a significant prognostic factor for worse survival and is associated with liver toxicity compared with pre-SBRT sarcopenia.

Stereotactic body radiotherapy versus radiofrequency ablation as initial treatment of small hepatocellular carcinoma

Background/Aim

Stereotactic body radiotherapy (SBRT) may be an alternative treatment for patients with small (≤3 cm) hepatocellular carcinomas (HCCs) who were not indicated for resection or local ablation therapy. This study compared the therapeutic effects of radiofrequency ablation (RFA) and SBRT in patients with small (≤3 cm) HCCs.

Methods

Data of HCC patients who underwent SBRT or RFA as an initial treatment at four tertiary referral hospitals between March 2011 and February 2017 were reviewed. The patient inclusion criteria were a single nodule measuring ≤3 cm in size and not suitable for resection.

Results

SBRT and RFA were performed for 72 (SBRT group) and 134 (RFA group) patients, respectively. The 1-, 3-, and 5-year overall survival (OS) rates were 97.0%, 80.3%, and 80.3%, respectively, in the SBRT group compared with 98.5%, 83.9%, and 80.8%, respectively, in the RFA group, with no significant differences between the groups (P = 0.81). The estimated five-year local control (LC) rate was 68.1% in the SBRT group and 73.1% in the RFA group (P = 0.81). In the SBRT group analysis, both SBRT alone (n = 34) and SBRT combined with transarterial chemoembolization (n = 38) showed no difference with RFA in OS (P = 0.72 and P = 0.90) or LC rate (P = 0.95 and P = 0.68), respectively.

Conclusion

SBRT is an effective and safe treatment method for small HCCs, with survival and tumor recurrence rates similar to those of RFA.

Modified Albumin-Bilirubin Model for Stratifying Survival in Patients with Hepatocellular Carcinoma Receiving Anticancer Therapy

Albumin−bilirubin (ALBI) grade is an objective and reproducible model for evaluating overall survival (OS) in patients with hepatocellular carcinoma (HCC). However, the original ALBI grade was established for patients with Child−Pugh classes A−C. HCC patients with Child−Pugh class C or poor performance status (Barcelona Clinic Liver Cancer (BCLC) stage D) usually receive hospice care. Thus, optimized cutoffs for the ALBI grade for stratifying OS in HCC patients receiving anticancer therapy are pertinent for accurate prognostication. This study retrospectively enrolled 2116 patients with BCLC stages A−C HCC after the exclusion of those ineligible for receiving anticancer therapy. The modified ALBI (mALBI) grades were: an ALBI score ≤−3.02 for mALBI grade 1, an ALBI score >−3.02 to ≤−2.08 for mALBI grade 2, and an ALBI score >−2.08 for mALBI grade 3. The original ALBI and mALBI grades were independent predictors of OS in all the enrolled patients and those receiving transarterial chemoembolization. In patients receiving curative therapy (radiofrequency ablation and surgical resection), the mALBI grade (grade 2 vs. 1 and grade 3 vs. 2) was an independent predictor of OS. Original ALBI grade 2 vs. 1 was an independent predictor of OS but not ALBI grade 3 vs. 2. The mALBI model can differentiate between patients with early, intermediate, or advanced HCC who received anticancer therapy into three prognostic groups. External validation of the proposed mALBI grade is warranted.

Combination Transarterial Chemoembolization and Stereotactic Body Radiation Therapy for Unresectable Single Large Hepatocellular Carcinoma: Results From a Prospective Phase 2 Trial

PURPOSE

Patients with hepatocellular carcinoma (HCC) at Barcelona Clinic Liver Cancer (BCLC) early-stage A (BCLC A) not suitable for surgery are first considered for ablation. Nonetheless, objective responses and long-term results for ablation in tumors larger than 3 to 4 cm are suboptimal, creating an unmet clinical need. This phase 2 trial studied combination of transarterial chemoembolization (TACE) and stereotactic body radiation therapy (SBRT) for BCLC A patients with a solitary HCC from 4 to 7 cm.

METHODS AND MATERIALS

Eligible patients were BCLC A, Child-Pugh score ≤7, Eastern Cooperative Oncology Group performance status 0 presenting with a single HCC from 4 to 7 cm not suitable for resection or liver transplantation. Treatment consisted of 2 sessions of drug-eluting bead-TACE within 1 month followed by immediate SBRT. SBRT delivered 35 to 50 Gy in 5 fractions. The primary endpoint was best objective response rate (ORR) by modified Response Evaluation Criteria in Solid Tumours (mRECIST). Secondary endpoints were overall survival (OS), progression-free survival (PFS), and toxic effects.

RESULTS

From 2014 to 2020, 32 were enrolled in a single institution with median follow-up of 37 months. Thirty patients had at least 1 posttreatment scan to assess response. ORR in the target lesion was 91%: 63% complete response (CR; n = 20), 28% partial response (n = 9), and 3% progression of disease (n = 1). Median time to CR was 10.1 months. Median OS was not yet reached and median PFS was 35 months. Patients achieving CR had a trend toward improved PFS (P = .09). Toxic effects were low.

CONCLUSIONS

This phase 2 trial showed very promising ORR when combining TACE + SBRT in large, unresectable HCC, which translates into excellent OS and PFS. These results provide the rationale for exploring this combination in larger phase 2 and 3 clinical trials and a space where SBRT might offer unique clinical advantage.