Stereotactic Body Radiotherapy for Small Unresectable Hepatocellular Carcinomas

SBRT vs. Y90: HCC Treatment Outcomes and Costs

OBJECTIVES

Stereotactic Body Radiotherapy (SBRT) and Yttrium-90 (Y90) are among the ablative therapies used as treatment options for localized hepatocellular carcinoma (HCC). To date, direct comparisons of the 2 modalities' outcomes and costs are lacking. This study aimed to analyze demographic, treatment, and cost information for patients with HCC treated with SBRT and Y90.

METHODS

Patients with HCC treated with SBRT or Y90 radioembolization between January 2018 and January 2020 at one institution were retrospectively reviewed. Demographic and treatment data were compared utilizing χ 2 tests. Kaplan-Meier curves and log-rank tests were applied to compare overall survival and progression-free survival in different treatment groups. Cox proportional hazard models were applied to analyze the unadjusted and adjusted survival differences. Ten SBRT and 10 Y90 patients were randomly selected for Medicare cost analysis.

RESULTS

Sixty-three patients received Y90, and 21 received SBRT. On univariable and multivariable analysis, there was no significant difference in overall survival or progression-free survival between the Y90 and SBRT cohorts. SBRT patients had higher American Joint Committee on Cancer staging ( P =0.039), greater tumor size (4.07 vs. 2.96 cm, P =0.013), and greater rates of prior liver-directed therapy (71.4% SBRT vs. 12.7% Y90, P <0.001). The average cost for SBRT was $15,148, and Y90 was $41,360.

CONCLUSIONS

SBRT and Y90 are effective therapies in the treatment of HCC, specifically having similar overall survival and progression-free survival. Y90 was found to have a significantly higher cost than SBRT. This study demonstrates the need for prospective studies to assess these modalities in treating HCC.

Verifying institutionally developed hybrid 3D-printed coaxial cylindrical phantom for patient-specific quality assurance in stereotactic body radiation therapy of hepatocellular carcinoma

An accurate and reliable patient-specific quality assurance (PSQA) is crucial to ensure the safety and precision of Stereotactic body radiation therapy (SBRT) in treating Hepatocellular carcinoma (HCC). This study examines the effectiveness of a novel hybrid 3D-printed hybrid coaxial cylindrical phantom for PSQA in the SBRT of HCC. The study compared three different point dose verification techniques for PSQA: a traditional solid water phantom, two dimensional detector array I'MatriXX, and a newly developed hybrid 3D-printed phantom. Thirty SBRT HCC liver cases were examined using these techniques, and point doses were measured and compared to planned doses using the perpendicular composite method with solid water and I'MatriXX phantoms. Unlike the other two methods, the point dose was compared in true composite geometry using the hybrid 3D-printed phantom, which enhanced the accuracy and consistency of PSQA. The study aims to assess the statistical significance and accuracy of the hybrid 3D-printed phantom compared to other methods. The results showed all techniques complied with the institutional threshold criteria of within ± 3% for point-dose measurement discrepancies. The hybrid 3D-printed phantom was found to have better consistency with a lower standard deviation than traditional methods. Statistical analysis using Student's t-test revealed the statistical significance of the hybrid 3D-printed phantom technique in patient-specific point-dose assessments with a p-value < 0.01. The hybrid 3D-printed phantom developed institutionally is cost-effective and easy to handle. It has been proven to be a valuable tool for PSQA in SBRT for the treatment of HCC and has demonstrated its practicality and reliability.

Role of Stereotactic Body Radiation Therapy in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC)is a common type of liver cancer with a poor prognosis, especially in patients with advanced stages or underlying liver disease. While surgical resection, liver transplantation, and ablation therapies have traditionally been the mainstay of treatment for HCC, radiation therapy has become increasingly recognized as an effective alternative, particularly for those who are not surgical candidates. Stereotactic Body Radiation Therapy (SBRT) is a highly precise form of radiation therapy that delivers very high doses of radiation to the tumor while sparing surrounding healthy tissue. Several studies have reported favorable outcomes with SBRT in HCC treatment. Moreover, SBRT can be used to treat recurrent HCC after prior treatment, offering a potentially curative approach in select cases. While SBRT has demonstrated its efficacy and safety in treating HCC, future studies are needed to further investigate the potential role of SBRT in combination with other treatments for HCC.

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.

Current Advances in the Treatment of Fibrolamellar Carcinoma of Liver

Fibrolamellar carcinoma (FLC) of the liver is a rare type of liver cancer that is prevalent in children and young adults, often less than 40 years old. The etiology is unclear. It presents without underlying liver disease with distinctive histological features such as fibrous collagen bands surrounding the tumor cells. Fusion protein DNAJB1-PRKACA is found in most of the cases. The prognosis of FLC is poor. Even though curative treatment option is surgery for a certain patient population, other treatment modalities including radiation, chemotherapy are currently being used without significant improvement of overall survival. Recently, targeted therapy and immunotherapy have been studied which may provide survival advantage in the future. This review sought to compile data from clinical trials and case reports/series to outline the current state of FLC treatment.

Fibrolamellar Hepatocellular Carcinoma: Comprehensive Review of Diagnosis, Imaging, and Management

BACKGROUND

Fibrolamellar hepatocellular carcinoma (FLC) is a rare malignancy that primarily affects patients in late adolescence and young adulthood. FLC tumors are characterized by their unique histologic features and a recently discovered genomic alteration, a chimeric fusion protein found in nearly all tumors. This review article provides the latest advancements in diagnosing, imaging, and managing FLC.

STUDY DESIGN

A comprehensive systematic review was performed using MEDLINE/PubMed and Web of Science databases, with the end of search date being July 1, 2022, regarding FLC diagnosis, imaging, and management.

RESULTS

Surgical resection remains the mainstay of therapy offering a chance for cure; however, given the incidence of metastatic disease at diagnosis and high rates of distant relapse, systemic therapies remain a crucial component of disease control. Unfortunately, few systemic therapies have demonstrated proven benefits. Consequently, recent efforts have galvanized around single-institute or small consortia-based studies specifically focused on enrolling patients with FLC or using agents with a biologic rationale.

CONCLUSIONS

FLC has unique demographic, radiologic, and pathologic features. The rarity of these tumors, coupled with the only recent acknowledgment of the genomic abnormality, has likely led to disease underrecognition and deprioritization of collaborative efforts to establish an evidence-based standard of care. Despite R0 resection, most patients experience recurrence. However, surgical resection is feasible for many recurrences and is associated with good survival. The role of chemotherapy is evolving, and further research is required to define its role in managing this disease.

Radiopaque drug-eluting embolisation beads as fiducial markers for stereotactic liver radiotherapy

Objective:

To determine the feasibility of using radiopaque (RO) beads as direct tumour surrogates for image-guided radiotherapy (IGRT) in patients with liver tumours after transarterial chemoembolisation (TACE).

Methods:

A novel vandetanib-eluting RO bead was delivered via TACE as part of a first-in-human clinical trial in patients with either hepatocellular carcinoma or liver metastases from colorectal cancer. Following TACE, patients underwent simulated radiotherapy imaging with four-dimensional computed tomography (4D-CT) and cone-beam CT (CBCT) imaging. RO beads were contoured using automated thresholding, and feasibility of matching between the simulated radiotherapy planning dataset (AVE-IP image from 4D data) and CBCT scans assessed. Additional kV, MV, helical CT and CBCT images of RO beads were obtained using an in-house phantom. Stability of RO bead position was assessed by comparing 4D-CT imaging to CT scans taken 6–20 days following TACE.

Results:

Eight patients were treated and 4D-CT and CBCT images acquired. RO beads were visible on 4D-CT and CBCT images in all cases and matching successfully performed. Differences in centre of mass of RO beads between CBCT and simulated radiotherapy planning scans (AVE-IP dataset) were 2.0 mm mediolaterally, 1.7 mm anteroposteriorally and 3.5 mm craniocaudally. RO beads in the phantom were visible on all imaging modalities assessed. RO bead position remained stable up to 29 days post TACE.

Conclusion:

RO beads are visible on IGRT imaging modalities, showing minimal artefact. They can be used for on-set matching with CBCT and remain stable over time.

Advances in knowledge:

The role of RO beads as fiducial markers for stereotactic liver radiotherapy is feasible and warrants further exploration as a combination therapy approach.

Report from the Western Canadian Gastrointestinal Cancer Consensus Conference Virtual Education Series-Transition from Local to System Therapy and Optimal Sequencing of Systemic Therapy for HCC

The Western Canadian Gastrointestinal Cancer Consensus Conference (WC-5) convened virtually on 10 February 2021. The WC-5 is an interactive multidisciplinary conference attended by health care professionals from across Western Canada (British Columbia, Alberta, Saskatchewan, and Manitoba) who are involved in the care of patients with gastrointestinal cancer. Surgical, medical, and radiation oncologists; pathologists; radiologists; and allied health care professionals participated in presentation and discussion sessions for the purpose of developing the recommendations presented here. This consensus statement addresses current issues in the management of hepatocellular cancer (HCC). Recommendations have been made for the transition from local to systemic therapy and the optimal sequencing of systemic regimens in the management of HCC.

Image-Guided Liver Stereotactic Body Radiotherapy Using VMAT and Real-Time Adaptive Tumor Gating: Evaluation of the Efficacy and Toxicity for Hepatocellular Carcinoma

Simple Summary

Although the use of stereotactic body radiation therapy (SBRT) in the management of hepatocellular carcinoma (HCC) remains unclear, it is a therapeutic option often considered in patients not eligible to or recurring after other local therapies. Liver SBRT can be delivered using a wide range of techniques and linear accelerators. We report the first evaluation for HCC of SBRT using volumetric modulated arc therapy (VMAT) and real-time adaptive tumor gating, which is a mainly completely non-invasive procedure (no fiducial markers for 65.2% of the patients). Our study showed that this SBRT technique has very favorable outcomes with optimal local control and a low toxicity rate.

Abstract

Liver SBRT is a therapeutic option for the treatment of HCC in patients not eligible for other local therapies. We retrospectively report the outcomes of a cohort of consecutive patients treated with SBRT for HCC at the Montpellier Cancer Institute. Between March 2013 and December 2018, 66 patients were treated with image-guided liver SBRT using VMAT and real-time adaptive tumor gating in our institute. The main endpoints considered in this study were local control, disease-free survival, overall survival, and toxicity. The median follow-up was 16.8 months. About 66.7% had prior liver treatment. Most patients received 50 Gy in five fractions of 10 Gy. No patient had local recurrence. Overall survival and disease-free survival were, respectively, 83.9% and 46.7% at one year. In multivariate analysis, the diameter of the lesions was a significant prognostic factor associated with disease-free survival (HR = 2.57 (1.19–5.53) p = 0.02). Regarding overall survival, the volume of PTV was associated with lower overall survival (HR = 2.84 (1.14–7.08) p = 0.025). No grade 3 toxicity was observed. One patient developed a grade 4 gastric ulcer, despite the dose constraints being respected. Image-guided liver SBRT with VMAT is an effective and safe treatment in patients with inoperable HCC, even in heavily pre-treated patients. Further prospective evaluation will help to clarify the role of SBRT in the management of HCC patients.

Fibrolamellar carcinoma: An entity all its own

Fibrolamellar carcinoma (FLC) is a rare malignant entity arising from the liver and primarily affecting patients in late adolescence and young adulthood. FLC tumors are characterized by their unique histologic features and an only recently discovered genomic alteration: a chimeric fusion protein found in nearly all tumors. The rarity of these tumors coupled with the only recent acknowledgement of this genomic abnormality has likely led to disease under-recognition and de-prioritization of collaborative efforts aimed at establishing an evidence-guided standard of care. Surgical resection undoubtedly remains a mainstay of therapy and a necessity for cure but given the incidence of metastatic disease at diagnosis and high rates of distant relapse, systemic therapies remain a key component of disease control. There are few systemic therapies that have demonstrated proven benefit. Recent efforts have galvanized around single-institute or small consortia-based studies specifically focused on the enrollment of patients with FLC or use of agents with biologic rationale. This review will outline the current state of FLC epidemiology, histology, biology and trialed therapies derived from available published literature.

Current Understanding of Ablative Radiation Therapy in Hepatocellular Carcinoma

The role of ablative stereotactic body radiotherapy (SBRT) in hepatocellular carcinoma (HCC) has been evolving over the last few decades. SBRT has mostly been used in early stages of HCC, including few (≤ 3 in number) tumors, small tumours (< 3 cm in size), as well as larger tumours which are ineligible for other ablative modalities, mostly without vascular invasion. In early stage HCC, SBRT is used as a definitive treatment with curative intent or with intent to bridge to liver transplant. Retrospective and prospective institutional series document a high rate of local control (68–95% at 3 years) following SBRT. This coupled with a low risk of toxicity makes this non-invasive ablative treatment an attractive option for patients who are ineligible for other ablative treatments. Small randomized studies of ablative radiation have also shown non-inferiority of radiation as compared to radiofrequency ablation (RFA). Currently, SBRT is widely available as a safe and effective liver directed therapy, although there is a need for more studies providing higher level evidence. This review gives a brief overview of SBRT and the evidence for its use in HCC patients with ablative intent.

Efficacy and Toxicity of Stereotactic Body Radiotherapy for Early to Advanced Stage Hepatocellular Carcinoma - Initial Experience From an Australian Liver Cancer Service

AIMS

Intrahepatic progression remains the predominant mode of cancer-related death in hepatocellular carcinoma (HCC) underscoring the need for effective local therapies. We report our initial experience with liver stereotactic body radiotherapy (SBRT) in the management of early to advanced stage HCC at an Australian tertiary liver cancer service.

MATERIALS AND METHODS

Patients with liver-confined HCC unsuitable for surgical resection or thermal ablation treated with SBRT between October 2013 and December 2018 were retrospectively evaluated. The primary end point was freedom from local progression. Secondary end points were progression-free survival, disease-specific survival, overall survival and toxicity.

RESULTS

Ninety-six patients were treated for 112 lesions (median size 3.8 cm, range 1.5-17 cm). The median follow-up was 13 months (range 3-65). Forty-six patients had received prior local therapies (median 1, range 1-5), 83 (86%) patients had cirrhosis with baseline Child-Pugh scores of A (88%) and B7-8 (12%). Fifty-nine (61%) patients had Barcelona Clinic Liver Cancer (BCLC) stage 0/A disease and 37 (39%) had stage B/C. Macrovascular invasion was present in 20 (21%). The median biologically effective dose (BED₁₀) was 86 and 60 Gy for the BCLC 0/A and B/C cohorts, respectively. Freedom from local progression at 18 months was 94% for BCLC 0/A and 74% for BCLC B/C. Progression-free survival and overall survival at 12 months were 80 and 95% for BCLC 0/A and 40 and 71% for BCLC B/C, respectively. Five patients (7%) with cirrhosis and without disease progression had an increase in Child-Pugh score >1 within 3 months of SBRT, four of whom had intercurrent infections. Clinical toxicities grade ≥2 were reported in 20% of patients.

CONCLUSION

SBRT is an effective ablative modality for early stage HCC with low rates of significant toxicity. Lower dose SBRT can provide durable local control for advanced stage HCC. However, out-of-field relapse remains common, providing a rationale to investigate SBRT in combination with other therapies.

Factors affecting target motion in stereotactic body radiotherapy of liver cancer using CyberKnife

INTRODUCTION

In stereotactic body radiation therapy (SBRT) of solitary liver cancer, organ motion due to respiration is an important factor in the definition of planning target volume (PTV). This study evaluated the potential associations of target motion with gross tumour volume (GTV) size, tumour location, Child-Pugh score and intra-fraction treatment time in SBRT of liver cancer treated by CyberKnife.

METHODS

Translational motion data of 145 liver cancer patients, who were previously treated by CyberKnife with free breathing under tumour tracking, were recorded in the log files of the motion tracking system and analysed. The factors including target location based on liver segments, Child-Pugh score which was an indication of liver cirrhosis, GTV size and intra-fraction treatment time were recorded and their associations with the magnitude of target movement were evaluated.

RESULTS

Target location demonstrated significant association with the translational target motion in the supero-inferior (SI) and left-right (LR) directions but less in antero-posterior (AP) direction. Tumours located at the peripheral segments were more affected than the central segments. Child-Pugh score and GTV size were not significantly associated with target motion in any direction. Longer intra-fraction treatment time generally increased target motion in the SI and LR directions.

CONCLUSION

In SBRT of liver cancer, the target motions in SI and LR directions were correlated with the location of target and treatment time, but not with Child-Pugh score and GTV size. These results should assist in deciding the GTV-PTV margin in SBRT treatment planning for solitary liver cancer.

Stereotactic Body Radiotherapy for Large Unresectable Hepatocellular Carcinomas - A Single Institution Phase II Study

AIMS

To evaluate the safety and efficacy of liver stereotactic body radiotherapy (SBRT) in the treatment of unresectable hepatocellular carcinomas (HCC) measuring >5 cm.

MATERIALS AND METHODS

Between November 2013 and February 2016, 13 patients with unresectable HCC (>5 cm), ineligible for other local treatments, with a Child-Pugh score (CPS) ≤ B7, were enrolled into a single-institution phase II study. SBRT was delivered by volumetric-modulated arc radiotherapy. Radiological response was reported using modified Response Evaluation Criteria in Solid Tumours criteria and toxicities graded by Common Terminology Criteria for Adverse Events v4 criteria.

RESULTS

Sixteen hepatomas (median size 7.5 cm, range 5.1-9.7 cm) were treated in 13 patients. The baseline CPS was A5/6 in nine patients (69%) and B7 in four patients (31%). Five patients (38%) received previous liver-directed treatment. The median prescribed dose was 45 Gy (range 40-45 Gy) in five fractions. The median follow-up was 17.7 months. The 1-year local control rate was 92%. The median overall survival was 17.7 months and the 1-year overall survival was 62%. The median time to local progression was not reached. Five patients (39%) had an increase in CPS by two or more points at 3 months. Overall, there were 10 grade 3 acute toxicities occurring in seven patients, of which six were haematological. Quality of life remained clinically stable or improved at 3 months in 61.5% and 53.8% of patients based on the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core-30 Global Health Score and Functional Assessment of Cancer Therapy - Hepatobiliary version 4 score, respectively.

CONCLUSIONS

In our cohort, SBRT to unresectable large HCC tumours provided excellent local control with acceptable toxicities. Regional recurrence remained the major cause of failure. Further studies are warranted to examine the role for SBRT in combination with other modalities to maximise disease control in the liver.

Scores of Child-Pugh Classification Impact Overall Survival After Stereotactic Body Radiation Therapy for Primary and Metastatic Liver Tumors

BACKGROUND

Stereotactic body radiotherapy (SBRT) delivers high-dose radiation to tumor tissues in few fractions, thereby reducing radiation damage to at-risk organs. There are more potential effects of SBRT owing to the higher biological equivalent dose delivered. Herein, we retrospectively analyzed its effectiveness and toxicity at our institution.

METHODS

Data from patients with hepatocellular carcinoma (HCC; n = 10) and liver metastases (n = 10) who underwent SBRT (total dose of 30-50 Gy in 5-10 fractions) between 2013 and 2016 were analyzed. Adverse events were recorded at the end of RT, 6 months after treatment, or upon death. Overall survival (OS) was calculated according to the biological effective dose (BED α/β = 10) and liver function (Child-Pugh [CP] classification 5 or 6 vs. 7 or 8) after SBRT, using Kaplan-Meier analyses.

RESULTS

Of the 20 patients, 6 declined the CP classification score after SBRT; grade 3 adverse events were not seen in any patient. A higher OS rate was seen in patients receiving a higher BED and in those with better CP classification after SBRT. Kaplan-Meier survival analysis yielded a median OS of 401 days and 1- and 2-year OS of 45% and 15%, respectively.

CONCLUSION

The higher BED was significantly associated with tumor control, and there were no differences in the tumor control rate between HCC and metastatic tumors. Changes in CP scores after SBRT also affected the survival rate. Good liver function may permit multiple rounds of SBRT.

[Liver stereotactic body radiotherapy: Clinical features and technical consequences, results. Which treatment machine in which situation?]

Liver stereotactic body radiotherapy is a developing technique for the treatment of primary tumours and metastases. Its implementation is complex because of the particularities of the treated organ and the comorbidities of the patients. However, this technique is a treatment opportunity for patients otherwise in therapeutic impasse. The scientific evidence of liver stereotactic body radiotherapy has been considered by the French health authority as insufficient for its widespread use outside specialized and experienced centers, despite a growing and important number of retrospective and prospective studies, but few comparative data. This article focuses on the specific features of stereotactic body radiotherapy for liver treatments and the results of published studies of liver stereotactic body radiotherapy performed with classic linear accelerators and dedicated radiosurgery units.

Current State of Liver-Directed Therapies and Combinatory Approaches with Systemic Therapy in Hepatocellular Carcinoma (HCC)

The increasing set of liver-directed therapies (LDT) have become an integral part of hepatocellular carcinoma (HCC) treatment. These range from percutaneous ablative techniques to arterial embolization, and varied radiotherapy strategies. They are now used for local disease control, symptom palliation, and bold curative strategies. The big challenge in the face of these innovative and sometimes overlapping technologies is to identify the best opportunity of use. In real practice, many patients may take benefit from LDT used as a bridge to curative treatment such as resection and liver transplantation. Varying trans-arterial embolization strategies are used, and comparison between established and developing technologies is scarce. Also, radioembolization utilizing yttrium-90 (Y-90) for locally advanced or intermediate-stage HCC needs further evidence of clinical efficacy. There is increasing interest on LDT-led changes in tumor biology that could have implications in systemic therapy efficacy. Foremost, additional to its apoptotic and necrotic properties, LDT could warrant changes in vascular endothelial growth factor (VEGF) expression and release. However, trans-arterial chemoembolization (TACE) used alongside tyrosine-kinase inhibitor (TKI) sorafenib has had its efficacy contested. Most recently, interest in associating Y-90 and TKI has emerged. Furthermore, LDT-led differences in tumor immune microenvironment and immune cell infiltration could be an opportunity to enhance immunotherapy efficacy for HCC patients. Early attempts to coordinate LDT and immunotherapy are being made. We here review LDT techniques exposing current evidence to understand its extant reach and future applications alongside systemic therapy development for HCC.