Stereotactic body radiation therapy for early-stage hepatocellular carcinoma - a systematic review on outcome

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.

Comparison of outcomes following surgical resection, percutaneous ablation or stereotactic body radiation therapy in early-stage, solitary and small (≤3 cm) treatment-naïve hepatocellular carcinoma

INTRODUCTION

Stereotactic body radiation therapy (SBRT) is associated with high local control rates in hepatocellular carcinoma (HCC). This study reports the outcomes of SBRT compared to surgical resection (SR) and percutaneous ablation (PA) for treatment-naïve, solitary HCCs ≤3 cm.

METHODS

This was a retrospective study of patients with BCLC stage 0/A HCC with a single ≤3 cm lesion, treated with curative intent between 2016 and 2020. SBRT was used for patients considered unsuitable for SR or PA. The co-primary endpoints were progression-free survival (PFS) and overall survival (OS). The secondary endpoints were treatment-related clinical toxicity rates and local control (LC) rates.

RESULTS

There were 112 patients included in this study. SBRT was delivered in 36 patients (32.1%), 51 had PA (45.5%) and 25 underwent SR (22.3%). Median follow-up was 23 months (range, 3-60 months) from diagnosis. The 3-year PFS and OS were 67% and 69% following SBRT, 55% and 80% following PA, and 85% and 100% following SR, respectively. Patients in the SR cohort had significantly better 3-year PFS and OS compared to SBRT and PA groups (p = 0.03 and p = 0.04, respectively). There was no significant difference in PFS (p = 0.15) or OS (p = 0.23) between SBRT and PA treated patients. The 3-year LC rate for the entire cohort was 98%.

CONCLUSIONS

In patients with treatment-naïve, early-stage solitary HCCs ≤3 cm, SBRT was associated with comparable PFS, OS and LC outcomes to PA. SBRT should be considered as a curative intent therapy to avoid treatment stage migration in this favourable prognostic cohort of patients.

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.

Tumor hypoxia and radiotherapy: A major driver of resistance even for novel radiotherapy modalities

Hypoxia in solid tumors is an important predictor of poor clinical outcome to radiotherapy. Both physicochemical and biological processes contribute to a reduced sensitivity of hypoxic tumor cells to ionizing radiation and hypoxia-related treatment resistances. A conventional low-dose fractionated radiotherapy regimen exploits iterative reoxygenation in between the individual fractions, nevertheless tumor hypoxia still remains a major hurdle for successful treatment outcome. The technological advances achieved in image guidance and highly conformal dose delivery make it nowadays possible to prescribe larger doses to the tumor as part of single high-dose or hypofractionated radiotherapy, while keeping an acceptable level of normal tissue complication in the co-irradiated organs at risk. However, we insufficiently understand the impact of tumor hypoxia to single high-doses of RT and hypofractionated RT. So-called FLASH radiotherapy, which delivers ionizing radiation at ultrahigh dose rates (> 40 Gy/sec), has recently emerged as an important breakthrough in the radiotherapy field to reduce normal tissue toxicity compared to irradiation at conventional dose rates (few Gy/min). Not surprisingly, oxygen consumption and tumor hypoxia also seem to play an intriguing role for FLASH radiotherapy. Here we will discuss the role of tumor hypoxia for radiotherapy in general and in the context of novel radiotherapy treatment approaches.

Therapeutic Outcome of Stereotactic Body Radiotherapy for Small Hepatocellular Carcinoma Lesions - A Systematic Review and Network Meta-analysis

Surgical resection, stereotactic body radiotherapy (SBRT) and radiofrequency ablation (RFA) have seldom been compared for small hepatocellular carcinoma (HCC). We explored the treatment outcomes of SBRT for small HCC by conducting a network meta-analysis (NMA). We compared the efficacy and safety of surgical resection, RFA and SBRT for liver-confined small HCC (three or fewer lesions with a diameter ≤5 cm). The study endpoint included the odds ratios of the 1-, 3- and 5-year progression/recurrence/disease-free survival (disease progression-free survival; DPFS) and overall survival rates, as well as severe complications. Forty-five studies included 21 468 patients. In the NMA with comparable data, SBRT had comparable 1-, 3- and 5-year DPFS but significantly worse pooled long-term overall survival (3- and 5-year overall survival) than surgical resection (odds ratio 1.39, 95% confidential interval 1.3-1.89; odds ratio 1.33, 95% confidence interval 1.06-1.69, respectively). SBRT was associated with significantly better pooled 1-year DPFS compared with RFA (odds ratio 0.39, 95% confidence interval 0.15-0.97), with the remaining outcomes being comparable. SBRT had significantly less incidence of severe complications compared with surgical resection (odds ratio 0.62, 95% confidence interval 0.42-0.88) and RFA (odds ratio 0.2, 95% confidence interval 0.03-0.94). In conclusion, for small HCCs (≤5 cm) with one to three nodules, SBRT may be favourable to reduce the risks of severe complications. In terms of DPFS, SBRT may be recommended as an alternative first-line therapy for RFA and surgical resection. The results regarding overall survival should be interpreted with caution, considering the potentially uneliminated bias. There is a clear need for well-designed randomised trials to conclusively identify real differences in efficacy between these treatments, especially SBRT and surgical resection.

Online verification of breath-hold reproducibility using kV-triggered imaging for liver stereotactic body radiation therapy

PURPOSE

To introduce a new technique for online breath-hold verification for liver stereotactic body radiation therapy (SBRT) based on kilovoltage-triggered imaging and liver dome positions.

MATERIAL AND METHODS

Twenty-five liver SBRT patients treated with deep inspiration breath-hold were included in this IRB-approved study. To verify the breath-hold reproducibility during treatment, a KV-triggered image was acquired at the beginning of each breath-hold. The liver dome position was visually compared with the expected upper/lower liver boundaries created by expanding/contracting the liver contour 5 mm in the superior-inferior direction. If the liver dome was within the boundaries, delivery continued; otherwise, beam was held manually, and the patient was instructed to take another breath-hold until the liver dome fell within boundaries. The liver dome was delineated on each triggered image. The mean distance between the delineated liver dome to the projected planning liver contour was defined as liver dome position error edome . The mean and maximum edome of each patient were compared between no breath-hold verification (all triggered images) and with online breath-hold verification (triggered images without beam-hold).

RESULTS

Seven hundred thirteen breath-hold triggered images from 92 fractions were analyzed. For each patient, an average of 1.5 breath-holds (range 0-7 for all patients) resulted in beam-hold, accounting for 5% (0-18%) of all breath-holds; online breath-hold verification reduced the mean edome from 3.1 mm (1.3-6.1 mm) to 2.7 mm (1.2-5.2 mm) and the maximum edome from 8.6 mm (3.0-18.0 mm) to 6.7 mm (3.0-9.0 mm). The percentage of breath-holds with edome >5 mm was reduced from 15% (0-42%) without breath-hold verification to 11% (0-35%) with online breath-hold verification. online breath-hold verification eliminated breath-holds with edome >10 mm, which happened in 3% (0-17%) of all breath-holds.

CONCLUSION

It is clinically feasible to monitor the reproducibility of each breath-hold during liver SBRT treatment using triggered images and liver dome. Online breath-hold verification improves the treatment accuracy for liver SBRT.

Comprehensive Treatment Uncertainty Analysis and PTV Margin Estimation for Fiducial Tracking in Robotic Liver Stereotactic Body Radiation Therapy

OBJECTIVE

This study aims to quantify the uncertainties of CyberKnife Synchrony fiducial tracking for liver stereotactic body radiation therapy (SBRT) cases, and evaluate the required planning target volume (PTV) margins.

METHODS

A total of 11 liver tumor patients with a total of 57 fractions, who underwent SBRT with synchronous fiducial tracking, were enrolled for the present study. The correlation/prediction model error, geometric error, and beam targeting error were quantified to determine the patient-level and fraction-level individual composite treatment uncertainties. The composite uncertainties and multiple margin recipes were compared for scenarios with and without rotation correction during treatment.

RESULTS

The correlation model error-related uncertainty was 4.3±1.8, 1.4±0.5 and 1.8±0.7 mm in the superior-inferior (SI), left-right, and anterior-posterior directions, respectively. These were the primary contributors among all uncertainty sources. The geometric error significantly increased for treatments without rotation correction. The fraction-level composite uncertainties had a long tail distribution. Furthermore, the generally used 5-mm isotropic margin covered all uncertainties in the left-right and anterior-posterior directions, and only 75% of uncertainties in the SI direction. In order to cover 90% of uncertainties in the SI direction, an 8-mm margin would be needed. For scenarios without rotation correction, additional safety margins should be added, especially in the superior-inferior and anterior-posterior directions.

CONCLUSION

The present study revealed that the correlation model error contributes to most of the uncertainties in the results. Most patients/fractions can be covered by a 5-mm margin. Patients with large treatment uncertainties might need a patient-specific margin.

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.

A web-based nomogram model for predicting the overall survival of hepatocellular carcinoma patients with external beam radiation therapy: A population study based on SEER database and a Chinese cohort

BACKGROUND

External beam radiation therapy (EBRT) for hepatocellular carcinoma (HCC) is rarely used in clinical practice. This study aims to develop and validate a prognostic nomogram model to predict overall survival (OS) in HCC patients treated with EBRT.

METHOD

We extracted eligible data of HCC patients between 2004 and 2015 from the Surveillance, Epidemiology, and End Results (SEER) database. Those patients were randomly divided into a training cohort (n=1004) and an internal validation cohort (n=429), and an external validation cohort composed of a Chinese cohort (n=95). A nomogram was established based on the independent prognostic variables identified from univariate and multivariate Cox regression analyses. The effective performance of the nomogram was evaluated using the concordance index (C-index), receiver operating characteristic curve (ROC), and calibration curves. The clinical practicability was evaluated using decision curve analysis (DCA).

RESULTS

T stage, N stage, M stage, AFP, tumor size, surgery, and chemotherapy were independent prognostic risk factors that were all included in the nomogram to predict OS in HCC patients with EBRT. In the training cohort, internal validation cohort, and external validation cohort, the C-index of the prediction model was 0.728 (95% confidence interval (CI): 0.716-0.740), 0.725 (95% CI:0.701-0.750), and 0.696 (95% CI:0.629-0.763), respectively. The 6-, 12-,18- and 24- month areas under the curves (AUC) of ROC in the training cohort were 0.835 、0.823 、0.810, and 0.801, respectively; and 0.821 、0.809 、0.813 and 0.804 in the internal validation cohort, respectively; and 0.749 、0.754 、0.791 and 0.798 in the external validation cohort, respectively. The calibration curves indicated that the predicted value of the prediction model performed well. The DCA curves showed better clinical practicability. In addition, based on the nomogram, we established a web-based nomogram to predict the OS of these patients visually.

CONCLUSION

Based on the SEER database and an independent external cohort from China, we established and validated a nomogram to predict OS in HCC patients treated with EBRT. In addition, for the first time, a web-based nomogram model can help clinicians judge the prognoses of these patients and make better clinical decisions.

Stereotactic Body Radiation Therapy for the Management of Hepatocellular Carcinoma: Efficacy and Safety

Simple Summary

This study aimed to describe treatment efficacy and safety in patients with hepatocellular carcinoma (HCC) undergoing stereotactic body radiation therapy (SBRT). In one of the largest retrospective studies to date, we analyzed the data of 318 patients. The median follow-up period was 70.2 months. The local control rate at 24 and 60 months was 94% (91–97%) and 94% (91–97%), respectively. Relapse-free survival at 12, 24, and 60 months was 62% (55–67%), 29% (23–36%), and 13% (8–19%), respectively. OS at 12, 24, and 60 months was 72% (95%CI 67–77%), 44% (38–50%), and 11% (7–15%), respectively. The outcome is highly related to the natural evolution of the underlying cirrhosis. Child-Pugh score B-C, high BCLC score, portal thrombosis, GTV volume, and higher PTV volume reported on total hepatic volume ratio were significantly associated with OS. SBRT is efficient for the management of HCC with a favorable toxicity profile.

Abstract

This study aimed to describe patient characteristics, treatment efficacy, and safety in patients with hepatocellular carcinoma (HCC) undergoing stereotactic body radiation therapy (SBRT). We retrospectively analyzed data of 318 patients with 375 HCC treated between June 2007 and December 2018. Efficacy (overall survival [OS], relapse-free survival, and local control) and acute and late toxicities were described. The median follow-up period was 70.2 months. Most patients were treated with 45 Gy in three fractions. The median (range) PTV volume was 90.7 (2.6–1067.6) cc. The local control rate at 24 and 60 months was 94% (91–97%) and 94% (91–97%), respectively. Relapse-free survival at 12, 24, and 60 months was 62% (55–67%), 29% (23–36%), and 13% (8–19%), respectively. OS at 12, 24, and 60 months was 72% (95%CI 67–77%), 44% (38–50%), and 11% (7–15%), respectively. Approximately 51% and 38% experienced acute and late toxicity, respectively. Child-Pugh score B-C, high BCLC score, portal thrombosis, high GTV volume, and higher PTV volume reported on total hepatic volume ratio were significantly associated with OS. SBRT is efficient for the management of HCC with a favorable toxicity profile. The outcome is highly related to the natural evolution of the underlying cirrhosis.

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.

Stereotactic body radiation therapy versus radiofrequency ablation in patients with small hepatocellular carcinoma: a systematic review and meta-analysis

Background

This study aimed to compare the clinical outcomes and toxicity between small hepatocellular carcinoma (HCC) patients treated with stereotactic body radiation therapy (SBRT) and those treated with radiofrequency ablation (RFA).

Methods

We searched databases for relevant clinical studies. The primary outcomes of interest were overall survival (OS) at 1 and 2 years, freedom from local progression (FFLP) rate at 2 years, and complications.

Results

Five cohorts from 5 retrospective studies and 4,814 patients with HCC were included. Pooled OS at 2 years was significantly lower for SBRT than for RFA [odds ratio (OR): 0.63; 95% confidence interval (CI): 0.51-0.79; P<0.0001], but the pooled FFLP rate at 2 years was higher for SBRT than for RFA (OR: 1.66; 95% CI: 1.05-2.61; P=0.03). In addition, there was no significant difference in the local and liver toxicities of the two treatments. The contradictory conclusion between the OS and FFLP outcome may be attributed to the difference in radiological dose and location, but there were no uniform criteria to illustrate the radiological dose and location in the included studies.

Conclusions

SBRT had a higher local control ratio but poorer prognosis than RFA in patients with small HCC. The local toxicity was comparable in both treatments. Further trials should be designed with uniform standards for SBRT and RFA treatments.

Silencing of Long Non-coding RNA TTN-AS1 Inhibits Hepatocellular Carcinoma Progression by the MicroRNA-134/ITGB1 Axis

BACKGROUND

Hepatocellular carcinoma (HCC) causes considerable mortality worldwide. Long non-coding RNA (lncRNA) TTN-AS1 has been recently identified as an oncogene in several cancers, but its role in HCC and the molecules remain largely unknown.

AIMS

The study aims to probe the function of lncRNA TTN-AS1 in HCC progression and the molecules involved.

METHODS

Differentially expressed lncRNAs between HCC and the adjacent normal tissues were analyzed using a microarray. TTN-AS1 expression in HCC and normal tissues and cells was determined. Targeting relationships between TTN-AS1 and miR-134 and between miR-134 and ITGB1 were validated. Artificial up-regulation or down-regulation of TTN-AS1, miR-134 and ITGB1 was introduced in HCC cells to probe their effects on the biological behaviors of HCC cells. Xenograft tumors were induced in nude mice for in vivo experiments.

RESULTS

TTN-AS1 and ITGB1 were highly expressed, while miR-134 was poorly expressed in HCC tissues. TTN-AS1 enforced ITGB1 expression through sequestering miR-134. Silencing of TTN-AS1 or over-expression of miR-134 inhibited proliferation, invasion, migration, and resistance to death of Huh7 cells. Following miR-134 silencing, further down-regulation of ITGB1 suppressed the malignant behaviors of HUH7 cells. The similar results were reproduced in vivo.

CONCLUSION

The current study provided evidence that TTN-AS1 might promote HCC progression through sponging miR-134 and the following ITGB1 up-regulation. TTN-AS1 may serve as a potential target for HCC treatment.

Stereotactic ablative radiotherapy for hepatocellular carcinoma: A systematic review and meta-analysis of local control, survival and toxicity outcomes

There is a growing body of literature supporting the use of stereotactic ablative body radiotherapy (SABR) in the management of primary hepatocellular carcinoma (HCC). This systematic review and meta-analysis of the current published evidence for SABR for HCC assessed the impact of treatment dose, fractionation and tumour size on the outcomes of local control (LC), overall survival (OS) and toxicity. A systematic search was independently performed by two authors for articles published in peer-reviewed journals between January 2005 and December 2019. A DerSimonian and Laird random effects model was used to assess pooled results. A multivariate meta-regression analysis incorporated the effect of explanatory variables (radiation dose in EQD2_[10], fractionation and tumour size) on outcomes of OS, LC and toxicity. Forty-nine cohorts involving 2846 HCC patients with 3088 lesions treated with SABR were included. Pooled 1-, 2- and 3-year LC rates were 91.1% (95% confidence interval [CI] 88.3-93.2), 86.7% (95% CI 82.7-89.8) and 84.2% (95% CI 77.9-88.9) respectively. Pooled 1-, 2- and 3-year OS rates were 78.4% (95% CI 73.4-82.6), 61.3% (55.2-66.9) and 48.3% (95% CI 39.0-57). Population-weighted median grade 3 toxicity rates were 6.5% (IQR 3.2-16) and mean grade 4/5 rates were 1.4% (IQR 0-2.1). Within EQD2_[10] ranges of 40 to 83.33 Gy corresponding to common dose-fractionation regimens of 30-50 Gy in 5 fractions, there was a multivariate association between superior LC and OS with increasing EQD2_[10] , with a proportionately smaller increase in grade 3 toxicity and no association with grade 4/5 toxicity. Stereotactic ablative body radiotherapy is a viable treatment option for HCC with high LC rates and low rates of reported grade 3/4 toxicity. Increasing EQD2_[10] was associated with improvements in LC and OS with a comparatively smaller increase in toxicity. Prospective randomised trials are warranted to define optimal patient selection and dose-fractionation regimens.

Frontiers of therapy for hepatocellular carcinoma

The incidence of hepatocellular carcinoma continues to increase worldwide. Fortunately, there have been notable recent advances in locoregional and systemic therapy. In this current review, we will highlight these new developments and future directions of hepatocellular carcinoma treatment and address the importance of a multidisciplinary approach to treatment.

Radiofrequency ablation versus stereotactic body radiotherapy for hepatocellular carcinoma: a meta-analysis

The present meta-analysis was performed to evaluate the efficacy of radiofrequency ablation (RFA) and stereotactic body radiotherapy (SBRT) in hepatocellular carcinoma (HCC) patients. A systematic literature search was conducted of online databases prior to February 21, 2021. Eleven articles involving 8429 patients were included. The pooled hazard ratio for overall survival (OS) of RFA versus SBRT was 0.79 (p < 0.001). Statistically significant differences were found in the 1-, 2-, 3-, 4- and 5-year pooled OS and freedom from local progression (FFLP) rates between the two groups, favoring the RFA arms. However, the pooled local control (LC) rates were higher in the SBRT arm. RFA provided better OS and FFLP for treating HCC, while SBRT achieved superior LC. PROSPERO registration number: CRD42020207877.

Australian recommendations for the management of hepatocellular carcinoma: a consensus statement

INTRODUCTION

Hepatocellular carcinoma (HCC) is a leading cause of cancer deaths both globally and in Australia. Surveillance for HCC in at-risk populations allows diagnosis at an early stage, when potentially curable. However, most Australians diagnosed with HCC die of the cancer or of liver disease. In the changing landscape of HCC management, unique challenges may lead to clinical practice variation. As a result, there is a need to identify best practice management of HCC in an Australian context. This consensus statement has been developed for health professionals involved in the care of adult patients with HCC in Australia. It is applicable to specialists, general medical practitioners, nurses, health coordinators and hospital administrators.

METHODS AND RECOMMENDATIONS

This statement has been developed by specialists in hepatology, radiology, surgery, oncology, palliative care, and primary care, including medical practitioners and nurses. The statement addresses four main areas relevant to HCC management: epidemiology and incidence, diagnosis, treatment, and patient management. A modified Delphi process was used to reach consensus on 31 recommendations. Principal recommendations include the adoption of surveillance strategies, use of multidisciplinary meetings, diagnosis, treatment options and patient management.

CHANGES IN MANAGEMENT AS A RESULT OF THIS STATEMENT

This consensus statement will simplify HCC patient management and reduce clinical variation. Ultimately, this should result in better outcomes for patients with HCC.

Stereotactic body radiotherapy in the management of hepatocellular carcinoma: An Australian multi-institutional patterns of practice review

INTRODUCTION

Stereotactic body radiotherapy (SBRT) is an emerging, therapeutic option in the management of hepatocellular carcinoma (HCC). A multicentre Liver Ablative Stereotactic Radiation (LASR) database was established to provide a collaborative platform for Australian institutions to define the practice of liver SBRT for HCC. This study explores the patterns of SBRT practice amongst Australian institutions.

METHODS

This was a multi-institutional retrospective study of patients treated with SBRT for HCC at 10 institutions between January 2013 and December 2019. Patients' demographics, disease characteristics and SBRT details were evaluated.

RESULTS

Three hundred and seventeen patients were evaluated with a median age of 67 years (range, 32-90). Liver cirrhosis was present in 88.6%, baseline Child-Pugh score was A5/6 in 85.1% and B7/8 in 13.2%. Median size of HCC treated was 30 mm (range, 10-280). 63.1% had early-stage disease (Barcelona clinic liver cancer (BCLC) stage 0/A) and 36% had intermediate/advanced-stage disease (BCLC B/C). In 2013/2014, six courses of SBRT were delivered, increasing to 108 in 2019. SBRT was prescribed in five fractions for 71.3% of the cohort. The most common dose fractionation schedule was 40 Gy in five fractions (24.3%). Median biologically effective dose (BED₁₀ ) delivered was 85.5 Gy for early-stage and 60 Gy for intermediate/advanced disease, respectively. The most common prescription range was 100-120 Gy BED₁₀ (32.8%).

CONCLUSION

SBRT utilisation for HCC is increasing in Australia. There was wide variation in size of tumours and disease stages treated, and prescription patterns. Uniform reporting of clinical and dosimetric details are important in refining the role of liver SBRT.

Therapeutic outcome and related predictors of stereotactic body radiotherapy for small liver-confined HCC: a systematic review and meta-analysis of observational studies

Background and purpose

Stereotactic body radiotherapy (SBRT) is a promising ablative modality for hepatocellular carcinoma (HCC) especially for those with small-sized or early-stage tumors. This study aimed to synthesize available data to evaluate efficacy and explore related predictors of SBRT for small liver-confined HCC (≤ 3 lesions with longest diameter ≤ 6 cm).

Materials and methods

A systematic search were performed of the PubMed and Cochrane Library databases. Primary endpoints were overall survival (OS) and local control (LC) of small HCC treated with SBRT, meanwhile, to evaluate clinical parameters associated with treatment outcome by two methods including subgroup comparisons and pooled HR meta-analysis. The secondary endpoint was treatment toxicity.

Results

After a comprehensive database review, 14 observational studies with 1238 HCC patients received SBRT were included. Pooled 1-year and 3-year OS rates were 93.0% (95% confidence interval [CI] 88.0–96.0%) and 72.0% (95% CI 62.0–79.0%), respectively. Pooled 1-year and 3-year LC rates were 96.0% (95% CI 91.0–98.0%) and 91.0% (95% CI 85.0–95.0%), respectively. Subgroup comparisons regarding Child–Pugh class (stratified by CP-A percentage 100%, 75–100%, 50–75%) showed there were statistically significant differences for both 1-year and 3-year OS rate (p < 0.01), while that regarding number of lesions, pretreatment situation, age (median/mean age of 65), macrovascular invasion, tumor size, and radiation dose (median BED₁₀ of 100 Gy), there were no differences. In subgroup comparisons for LC rate, it showed number of lesions (1 lesion vs. 2–3 lesions) was significantly associated with 1-year LC rate (p = 0.04), though not associated with 3-year LC rate (p = 0.72). In subgroup comparisons categorized by other factors including pretreatment situation, age, CP-A percentage, macrovascular invasion, tumor size, and radiation dose, there were no significant differences for 1- or 3-year LC rate. To further explore the association between CP class and OS, the second method was applied by combining HR and 95% CIs. Results indicated CP-A was predictive of better OS (p = 0.001) with pooled HR 0.31 (95% CIs 0.11–0.88), which was consistent with subgroup comparison results. Concerning adverse effect of SBRT, pooled rates of grade ≥ 3 hepatic complications and RILD were 4.0% (95% CI 2.0–8.0%) and 14.7% (95% CI 7.4–24.7%), respectively.

Conclusion

The study showed that SBRT was a potent local treatment for small liver-confined HCC conferring excellent OS and LC persisting up to 3 years, even though parts of included patients were pretreated or with macrovascular invasion. CP-A class was a significant predictor of optimal OS, while number of lesions might affect short term tumor control (1-year LC). Tumor size and radiation dose were not vital factors impacting treatment outcome for such small-sized HCC patients. Because of the low quality of observational studies and heterogeneous groups of patients treated with SBRT, further clinical trials should be prospectively investigated in large sample sizes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13014-021-01761-1.

Stereotactic radiotherapy for hepatocellular carcinoma: Expanding the multidisciplinary armamentarium

Hepatocellular carcinoma (HCC) is the fifth most common malignancy worldwide and the third most common cause of cancer-related death. Long-term prognosis remains poor with treatment options frequently limited by advanced tumor stage, tumor location, or underlying liver dysfunction. Stereotactic ablative body radiotherapy (SABR) utilizes technological advances to deliver highly precise, tumoricidal doses of radiation. There is an emerging body of literature on SABR in HCC demonstrating high rates of local control in the order of 80-90% at 3 years. SABR is associated with a low risk of radiation-induced liver disease or decompensation in appropriately selected HCC patients with compensated liver function and is now being incorporated into guidelines as an additional treatment option. This review outlines the emerging role of SABR in the multidisciplinary management of HCC and summarizes the current evidence for its use as an alternative ablative option for early-stage disease, as a bridge to transplant, and as palliation for advanced-stage disease. We outline specific considerations regarding patient selection, toxicities, and response assessment. Finally, we compare current international guidelines and recommendations for the use of SABR and summarize ongoing studies.

Survival and morbidity following stereotactic radiotherapy of hepatocellular carcinoma: a ten-year, single institution experience

BACKGROUND AND AIM

Stereotactic ablative body radiotherapy (SABR) is an emerging treatment option in hepatocellular carcinoma (HCC) in patients ineligible for other local ablative therapies. This study reports on the safety and efficacy of SABR in a Danish cohort of HCC patients.

MATERIALS AND METHODS

Between January 2009 and December 2018, 28 patients with HCCs were treated with SABR at our institution. The primary endpoint of this retrospective study was local control; secondary endpoints were progression-free survival, overall survival and toxicity.

RESULTS

In 28 patients, 32 tumors (median size 3.7 cm, range 1.4-6.8 cm) were treated. The median follow-up time was 16 months. Most patients (68%) received previous liver-directed treatments. A dose of 48 Gy in three or six fractions were given to 43% of the patients. Grad 1 or 2 toxicity was reported in 13 patients (46%), whereas 4 patients (14%) needed hospitalization (grade 3). One-year local control and overall survivals were 90% and 71%, respectively. One-year progression-free survival was 32%, and 65% of patients with disease progression received further HCC therapy. In univariate analysis, none of the examined factors predicted recurrence or overall survival.

CONCLUSION

SABR provides high local control to inoperable HCC. SABR can be delivered safely even after previous liver-directed therapies and subsequent therapies are feasible after treatment with SABR. Despite excellent local control, disease progression outside of the irradiated site remains prominent. Further studies are warranted to examine combined therapy approaches to maximize disease control.

Intrafraction cone beam computed tomography verification of breath hold during liver stereotactic radiation therapy

INTRODUCTION

Intrafraction imaging is an Elekta feature that enables cone beam computed tomography (CBCT) acquisition simultaneously with treatment arc delivery. It has facilitated the introduction of breath-hold (BH) gated stereotactic body radiation therapy (SBRT) by enabling visualisation of tumour and organs at risk during treatment. The aims of this study were to assess BH reproducibility and use intrafraction CBCT (IF-CBCT) to quantify any variation in diaphragm position (diaphragmatic feathering) during the multiple BHs performed during each arc.

METHODS

IF-CBCTs for consecutive liver SBRT patients where BH was achieved using the Elekta Active Breathing Control (ABC) system were retrospectively evaluated. Average intrafraction couch shifts for deep-inspiration BH (DIBH) or end-expiration BH (EEBH) were recorded as an indication of reproducibility. Diaphragmatic feathering was quantified by measuring the difference between the most superior and inferior visible edges of the diaphragm on IF-CBCTs.

RESULTS

A total of 212 images from 30 patients were reviewed. Twenty-two (73.3%) patients were treated in EEBH. The mean intrafraction shift was similar between DIBH and EEBH groups with the largest mean shift of 0.22cm occurring in the superior-inferior direction. Mean diaphragmatic feathering was similar between the DIBH and EEBH groups, 0.09cm (0-0.44cm) and 0.14cm (0-1.89cm) respectively. A higher percentage of EEBH patients demonstrated no diaphragmatic feathering throughout treatment compared with DIBH patients (31.8% vs 25%).

CONCLUSION

The results of this study indicate that BH is reproducible in both DIBH and EEBH for liver SBRT treatment using the ABC system. Appropriate patient selection and BH coaching prior to CT simulation are critical to its success.

Stereotactic Radiotherapy for Hepatocellular Carcinoma, Radiosensitization Strategies and Radiation-Immunotherapy Combination

Simple Summary

Radiotherapy is rapidly turning into a crucial component of multidisciplinary treatment for liver cancer because many patients are not surgical treatment candidates. Thanks to technical developments, radiotherapy have achieved high precision treatments, making it possible to eliminate tumor cells without severe damage to the liver and other organs. Stereotactic Body Radiation Therapy is an advanced radiotherapy technique able to eradicate malignant tumors wherever they are located in properly selected patients. The best use of radiotherapy, the most fruitful radiotherapy strategy, and the best way to combine it with other treatments for liver cancer are largely unknown. Radiosensitizers, agents that can potentiate radiotherapy, could broaden the radiotherapeutic landscape. Radiotherapy potentiation can be achieved with diverse treatments, not only drugs but also nanoparticles. In order to clear up the performance of radiotherapy in liver cancer management in the future and the best ways to potentiate its effects, considerable medical research is needed.

Abstract

Stereotactic body radiotherapy (SBRT) is an emerging ablative modality for hepatocellular carcinoma (HCC). Most patients with HCC have advanced disease at the time of diagnosis, and therefore, are not candidates for definitive-intent therapies such as resection or transplantation. For this reason, various alternative local and regional therapies have been used to prevent disease progression, palliate symptoms, and delay liver failure. Stereotactic body radiation therapy is a non-invasive technique of delivering ablative doses of radiation to tumors while sparing normal or non-tumor hepatic tissue. Incorporation of SBRT in multidisciplinary HCC management is gradual, initially applied when other liver-directed therapies have failed or are contraindicated, and tried in combination with other locoregional or systemic therapies for more unfavorable conditions by more experienced teams. In order to improve SBRT therapeutic ratio, there has been much interest in augmenting the effect of radiation on tumors by combining it with chemotherapy, molecularly targeted therapeutics, nanoparticles, and immunotherapy. This review aims to synthesize available evidence to evaluate the clinical feasibility and efficacy of SBRT for HCC, and to explore novel radio-potentiation concepts by combining SBRT with novel therapeutics. It is expected that those approaches would result in improved therapeutic outcomes, even though many questions remain with regard to the optimal way to assemble treatments. Further trials are needed to evaluate and consolidate these promising therapies for HCC.

Optimizing the management of intermediate-stage hepatocellular carcinoma: Current trends and prospects

Hepatocellular carcinoma (HCC) is usually accompanied by chronic liver damage, which sometimes influences the selection of HCC treatment. The Barcelona Clinic Liver Cancer (BCLC) staging system, which was first introduced in 1999, is the most commonly used worldwide. Although the intermediate-stage (BCLC stage B) includes the largest number and heterogeneous HCC patients, the recommended treatment option is transarterial chemoembolization (TACE) only. However, recent progress in radical treatments such as hepatic resection, liver transplantation, radiation therapy, and percutaneous therapy has made it possible to treat selected patients with BCLC stage B HCC. Radical treatments are expected to prolong survival time. To-date, TACE has also progressed. In addition to conventional TACE, balloon-occluded TACE and drug-eluting beads TACE are available. These new modalities of TACE will improve therapeutic efficacy and reduce adverse events. One of the most serious concerns of TACE is that repeated TACE reduces the treatment effect and induces liver function impairment. The decision on when TACE should be interrupted is complex. Many molecular targeted agents are now available, and immune checkpoint inhibitors will soon be available for HCC patients with Child-Pugh class A worldwide. Under these circumstances, in patients with TACE unsuitability, switching to molecular targeted agents before deterioration of liver function might improve the prognosis compared to repeated TACE. We should pay attention to stop TACE in TACE-unsuitable HCC patients as it can induce the deterioration of liver function.

Advances in Radiobiology of Stereotactic Ablative Radiotherapy

Radiotherapy (RT) has been developed with remarkable technological advances in recent years. The accuracy of RT is dramatically improved and accordingly high dose radiation of the tumors could be precisely projected. Stereotactic radiosurgery (SRS) and stereotactic body radiotherapy (SBRT), also known as stereotactic ablative radiotherapy (SABR), are rapidly becoming the accepted practice in treating solid small sized tumors. Compared with the conventional fractionation external beam radiotherapy (EBRT), SABR with very high dose per fraction and hypo-fractionated irradiation yields convincing and satisfied therapeutic effects with low toxicity, since tumor cells could be directly ablated like radiofrequency ablation (RFA). The impressive clinical efficacy of SABR is greater than expected by the linear quadratic model and the conventional radiobiological principles, i.e., 4 Rs of radiobiology (reoxygenation, repair, redistribution, and repopulation), which may no longer be suitable for the explanation of SABR's ablation effects. Based on 4 Rs of radiobiology, 5 Rs of radiobiology emphasizes the intrinsic radiosensitivity of tumor cells, which may correlate with the responsiveness of SABR. Meanwhile, SABR induced the radiobiological alteration including vascular endothelial injury and the immune activation, which has been indicated by literature reported to play a crucial role in tumor control. However, a comprehensive review involving these advances in SABR is lacking. In this review, advances in radiobiology of SABR including the role of the 4 Rs of radiobiology and potential radiobiological factors for SABR will be comprehensively reviewed and discussed.