Stereotactic body radiation therapy for hepatocellular carcinoma: from infancy to ongoing maturity

Quality of care in hepatocellular carcinoma-A critical review

There is significant variation in HCC management across different centers with poor adherence to evidence-based clinical practice guidelines as assessed in prior studies. In Australia, quality indicators (QIs) have recently been proposed by a multidisciplinary group of experts to help provide a framework to assess and monitor the quality of HCC care. In this review, we discuss the many areas where real-world practice deviates from evidence-based medicine, the role that QI sets play in addressing this gap, and the similarities and differences between Australian QIs and other leading treatment guidelines and QI sets from around the world. We focus on the utility of QI sets to identify opportunities for targeted improvement in the real-world clinical environment. We conclude with a discussion about the formation of a national clinical quality registry as a long-term measure to facilitate continual improvements in patient care within and across sites in order to optimize patient outcomes.

Liver diseases and hepatocellular carcinoma in the Asia-Pacific region: burden, trends, challenges and future directions

Globally, nearly half of deaths from cirrhosis and chronic liver diseases (CLD) and three-quarters of deaths from hepatocellular carcinoma (HCC) occur in the Asia-Pacific region. Chronic hepatitis B is responsible for the vast majority of liver-related deaths in the region. Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most common form of CLD, affecting an estimated 30% of the adult population. Compared with people of European descent, people from the Asia-Pacific region carry more genetic variants associated with MASLD and its progression. Alcohol is a fast-growing cause of CLD and HCC in Asia as a result of the rising per-capita consumption of alcohol. Drug-induced liver injury is under-recognized and probably has a high prevalence in this region. The epidemiological and outcome data of acute-on-chronic liver failure are heterogeneous, and non-unified definitions across regions contribute to this heterogeneity. CLDs are severely underdiagnosed, and effective treatments and vaccinations are underutilized. In this Review, we highlight trends in the burden of CLD and HCC in the Asia-Pacific region and discuss the rapidly changing aetiologies of liver disease. We examine the multiple gaps in the care cascade and propose mitigating strategies and future directions.

Application of nanotechnology in the treatment of hepatocellular carcinoma

Hepatocellular carcinoma is the predominant histologic variant of hepatic malignancy and has become a major challenge to global health. The increasing incidence and mortality of hepatocellular carcinoma has created an urgent need for effective prevention, diagnosis, and treatment strategies. This is despite the impressive results of multiple treatments in the clinic. However, the unique tumor immunosuppressive microenvironment of hepatocellular carcinoma increases the difficulty of treatment and immune tolerance. In recent years, the application of nanoparticles in the treatment of hepatocellular carcinoma has brought new hope for tumor patients. Nano agents target tumor-associated fibroblasts, regulatory T cells, myeloid suppressor cells, tumor-associated macrophages, tumor-associated neutrophils, and immature dendritic cells, reversed the immunosuppressive microenvironment of hepatocellular carcinoma. In addition, he purpose of this review is to summarize the advantages of nanotechnology in guiding surgical excision, local ablation, TACE, standard chemotherapy, and immunotherapy, application of nano-vaccines has also continuously enriched the treatment of liver cancer. This study aims to investigate the potential applications of nanotechnology in the management of hepatocellular carcinoma, with the ultimate goal of enhancing therapeutic outcomes and improving the prognosis for patients affected by this malignancy.

LINC02466 promotes the progression of hepatocellular carcinoma through the mTOR pathway

OBJECTIVE

Long non-coding RNAs (lncRNAs) LINC02466 is an lncRNA newly linked to the adverse outcomes in primary liver cancer patients, and its crucial involvement in the disease's escalation. Decoding the specific role of LINC02466 in HCC progression is of great significance to provide a potential therapeutic target for HCC.

METHODS

RT-qPCR and Western Blot techniques was used to analyze the expression levels of LINC02466 in both malignant and surrounding healthy liver tissues. CCK8 assays and colony formation experiments indicates the LINC02466's effect on the proliferation rates of liver cancer cells. Flow cytometry was pivotal in revealing its significant influence on the cell cycle of these cells. Kaplan-Meier survival analysis with log-rank tests were employed.

RESULTS

The suppression of LINC02466 markedly reduces the stemness attributes of liver cancer cells, indicating a potential therapeutic target. LINC02466 overexpression significantly increased tumor growth rates and final volumes. Further research indicated that LINC02466 significantly influences liver cancer progression through regulating the mTOR signaling pathway.

CONCLUSION

LINC02466 regulating cell proliferation, the cell cycle, and stemness characteristics via the mTOR pathway, suggesting LINC02466 as a potential therapeutic target for primary liver cancer.

Long-term outcomes of more than a decade treating patients with stereotactic body radiation therapy for hepatocellular carcinoma

Purpose/Objectives

To evaluate if stereotactic body radiotherapy (SBRT) for hepatocellular carcinoma (HCC) has a durable effect on tumor control and can be delivered safely.

Materials/Methods

Patients included in this retrospective study have been treated at our institution from January 2008 to December 2022. Eligibility criteria were diagnosis of HCC, BCLC stage 0-A-B, non-cirrhotic liver or liver with cirrhosis Child-Pugh class A, and a maximum of three lesions with a cumulative diameter of ≤ 6 cm. Patients with relapses after surgery, thermal ablation or TACE or patients awaiting transplant were also candidates for SBRT. SBRT was delivered in 6 fractions of 8 or 9 Gy. The primary endpoint was local (target) control (LC). Secondary endpoints were time to progression (TTP), overall survival (OS), response rate (RR) and toxicity.

Results

A total of 52 patients received SBRT at our institution and 51 were included in this study. One patient objected and was excluded. Median follow-up was 2.1 years for LC and 2.3 years for OS. Median tumor size was 26 mm. LC rates at 1, 2, and 5 years were 100 %, 95 % and 95 % respectively. Median TTP was 45.6 months. Median OS was 7.1 years. RR was 96 %. No patients in this study have experienced SBRT related CTC AE grade ≥ 3 toxicity.

Conclusion

SBRT resulted in excellent long-term local control rates and absence of severe toxicity in a group of HCC patients. The reported outcomes compare favorably with other local therapies. SBRT should be considered as one of the available local treatment options for HCC.

Radiomic feature robustness in CT scans affected by fiducial marker induced streak artifacts for patients with hepatocellular carcinoma

BACKGROUND

Stereotactic body radiation therapy for hepatocellular carcinoma necessitates the implantation of gold fiducial markers in the liver, resulting in artifacts on computed tomography (CT) scans, which affect radiomic feature values.

PURPOSE

This report aims to assess the effect of these artifacts on radiomic features and how removing CT slices affects radiomic features extracted from 3D regions of interest (ROI).

METHODS

First, the range variation in 38 tumor contours unaffected by artifacts was assessed after sequentially and randomly removing 25%, 50%, 75% of slices. Subsequently, the agreement of feature values before and after removing ROI slices containing artifacts from 186 patients' CT scans was assessed with Lin's concordance correlation coefficient (CCC) and a Wilcoxon signed-rank test.

RESULTS

In artifact-free tumor volumes, at least 71% of features remain robust with up to 50% of slices removed, while 56% remains robust with up to 75% of slices removed. When comparing contours before and after removing slices containing artifacts, around a third of features in the tumor contour and surrounding area remain robust (CCC > 0.9), compared to 44% in the healthy liver. Concerning the tumor, 13% (Gray Level Size Zone Matrix) to 61% (first order) of the features remain robust (CCC > 0.9). Over 90% of features differ significantly as assessed by Wilcoxon signed-rank test, however.

CONCLUSIONS

This study demonstrates that removing slices containing artifacts is a feasible solution for the CT fiducial problem in this patient population and provides insight into which features are affected.

CT/MRI LI-RADS 2024 Update: Treatment Response Assessment

With the rising incidence of hepatocellular carcinoma, there has been increasing use of local-regional therapy (LRT) to downstage or bridge to transplant, for definitive treatment, and for palliation. The CT/MRI Liver Imaging Reporting and Data System (LI-RADS) Treatment Response Assessment (TRA) algorithm provides guidance for step-by-step tumor assessment after LRT and standardized reporting. Current evidence suggests that the algorithm performs well in the assessment of tumor response to arterial embolic and loco-ablative therapies and fair when assessing response to radiation-based therapies, with limited data to validate the latter. Both evidence-based and expert-based refinements of the algorithm are needed to improve its diagnostic accuracy after varying types of LRT. This review provides an overview of the challenges and limitations of the LI-RADS TRA algorithm version 2017 and discusses the refinements introduced in the updated 2024 LI-RADS algorithm for CT/MRI.

Stereotactic body radiotherapy is an alternative to radiofrequency ablation for single HCC ≤5.0 cm

Background & Aims

Radiation therapy has been refined with increasing evidence of the benefits of stereotactic body radiation therapy (SBRT) in treating hepatocellular carcinoma (HCC). In this study, we aimed to evaluate whether SBRT could serve as an alternative to radiofrequency ablation (RFA) for small HCC with a single lesion ≤5.0 cm.

Methods

Patients with a single HCC lesion ≤5.0 cm who received RFA or SBRT were included. Cumulative local/distant recurrence rate, progression-free survival, overall survival, adverse events and subsequent treatments after recurrence were analyzed.

Results

A total of 288 patients receiving RFA (n = 166) or SBRT (n = 122) were enrolled. The baseline characteristics between the two groups were comparable. The cumulative local recurrence rate in the SBRT group was significantly lower than that in the RFA group (hazard ratio [HR] 0.30, 95% CI 0.16-0.57, p <0.001), especially for patients with tumours >2.0 cm (HR 0.20, 95% CI 0.08-0.50, p <0.001) or adjacent to major vessels (HR 0.29, 95% CI 0.13-0.66, p <0.001). Cumulative distant recurrence rate, progression-free survival and overall survival were not significantly different between the two groups (all p >0.050). Adverse events were mild and easily reversible. However, more patients in the SBRT group suffered from Child-Pugh score and total bilirubin increases. More treatment options after recurrence or progression might be available for patients in the RFA group compared to those in the SBRT group (p <0.001).

Conclusions

Both RFA and SBRT were effective and safe for HCC with a single lesion ≤5.0 cm. SBRT could be an alternative treatment to RFA, especially for tumours >2.0 cm or adjacent to major vessels.

Impact and implications

Stereotactic body radiation therapy (SBRT) may be used as an alternative treatment to thermal ablation for patients with BCLC stage A hepatocellular carcinoma (HCC) who are not candidates for surgical resection, including those with tumours >3 cm and those with 1 to 3 tumours. This study focused on HCC patients with a specific tumour burden, namely a single lesion ≤5.0 cm, demonstrating that SBRT could be an effective and safe alternative to radiofrequency ablation (RFA), especially for those with tumours >2.0 cm or adjacent to major vessels. The findings of this study provided robust empirical evidence supporting the utilization of SBRT in treating small HCC, while also establishing a solid foundation for future prospective clinical investigations.

Evaluating ECM stiffness and liver cancer radiation response via shear-wave elasticity in 3D culture models

BACKGROUND

The stiffness of the tumor microenvironment (TME) directly influences cellular behaviors. Radiotherapy (RT) is a common treatment for solid tumors, but the TME can impact its efficacy. In the case of liver cancer, clinical observations have shown that tumors within a cirrhotic, stiffer background respond less to RT, suggesting that the extracellular matrix (ECM) stiffness plays a critical role in the development of radioresistance.

METHODS

This study explored the effects of ECM stiffness and the inhibition of lysyl oxidase (LOX) isoenzymes on the radiation response of liver cancer in a millimeter-sized three-dimensional (3D) culture. We constructed a cube-shaped ECM-based millimeter-sized hydrogel containing Huh7 human liver cancer cells. By modulating the collagen concentration, we produced two groups of samples with different ECM stiffnesses to mimic the clinical scenarios of normal and cirrhotic livers. We used a single-transducer system for shear-wave-based elasticity measurement, to derive Young's modulus of the 3D cell culture to investigate how the ECM stiffness affects radiosensitivity. This is the first demonstration of a workflow for assessing radiation-induced response in a millimeter-sized 3D culture.

RESULTS

Increased ECM stiffness was associated with a decreased radiation response. Moreover, sonoporation-assisted LOX inhibition with BAPN (β-aminopropionitrile monofumarate) significantly decreased the initial ECM stiffness and increased RT-induced cell death. Inhibition of LOX was particularly effective in reducing ECM stiffness in stiffer matrices. Combining LOX inhibition with RT markedly increased radiation-induced DNA damage in cirrhotic liver cancer cells, enhancing their response to radiation. Furthermore, LOX inhibition can be combined with sonoporation to overcome stiffness-related radioresistance, potentially leading to better treatment outcomes for patients with liver cancer.

CONCLUSIONS

The findings underscore the significant influence of ECM stiffness on liver cancer's response to radiation. Sonoporation-aided LOX inhibition emerges as a promising strategy to mitigate stiffness-related resistance, offering potential improvements in liver cancer treatment outcomes.

Current Insights into Molecular Mechanisms and Potential Biomarkers for Treating Radiation-Induced Liver Damage

Highly conformal delivery of radiation therapy (RT) has revolutionized the treatment landscape for primary and metastatic liver cancers, yet concerns persist regarding radiation-induced liver disease (RILD). Despite advancements, RILD remains a major dose-limiting factor due to the potential damage to normal liver tissues by therapeutic radiation. The toxicity to normal liver tissues is associated with a multitude of physiological and pathological consequences. RILD unfolds as multifaceted processes, intricately linking various responses, such as DNA damage, oxidative stress, inflammation, cellular senescence, fibrosis, and immune reactions, through multiple signaling pathways. The DNA damage caused by ionizing radiation (IR) is a major contributor to the pathogenesis of RILD. Moreover, current treatment options for RILD are limited, with no established biomarker for early detection. RILD diagnosis often occurs at advanced stages, highlighting the critical need for early biomarkers to adjust treatment strategies and prevent liver failure. This review provides an outline of the diverse molecular and cellular mechanisms responsible for the development of RILD and points out all of the available biomarkers for early detection with the aim of helping clinicians decide on advance treatment strategies from a single literature recourse.

Stereotactic body radiation therapy (SBRT) in patients with hepatocellular cancer-a narrative review and expert opinion

Background and Objective

Stereotactic body radiation therapy (SBRT) is a highly conformal technique of external beam radiotherapy precisely delivering high total (ablative) doses in a small number of fractions to clearly defined target volumes. Its development enabled efficient and safe radiation treatments in patients with localized hepatocellular cancer (HCC) unsuitable for other local treatment options. Moreover, it can be easily combined with several other therapy approaches. Thus, the aim of this narrative review is to outline the current role of SBRT in the multifocal treatment of HCC patients.

Methods

We searched PubMed for articles dealing with SBRT alone, in combination with other local or systemic treatments or in comparison to other local treatments in patients with HCC. This included original articles, reviews and conceptional articles dealing with the technique of SBRT. All articles were analysed for suitability by two independent reviewers.

Key Content and Findings

This review summarizes the currently available evidence for SBRT as a definitive treatment for HCC as well as its role within combination approaches including bridging to transplantation. SBRT is an effective and safe definitive treatment option in patients with localized HCC unsuitable for surgery and/or other local therapies based on retrospective and prospective series. Its combination with other local treatments yields superior results compared to single modality treatment based on non-randomized data. A growing number of prospective trials confirmed at least similar if not superior rates of local control with low toxicities compared to well established other local treatments even in non-selected patients.

Conclusions

SBRT is a promising tool in the treatment of HCC. It can be used either as definitive treatment, within combination approaches or as a bridging tool. Several phase III trials comparing SBRT with other local options are ongoing, which will further clarify its encouraging role.

Initial Trans-Arterial Chemo-Embolisation (TACE) Is Associated with Similar Survival Outcomes as Compared to Upfront Percutaneous Ablation Allowing for Follow-Up Treatment in Those with Single Hepatocellular Carcinoma (HCC) ≤ 3 cm: Results of a Real-World Propensity-Matched Multi-Centre Australian Cohort Study

Percutaneous ablation is recommended in Barcelona Clinic Liver Cancer (BCLC) stage 0/A patients with HCC ≤3 cm as a curative treatment modality alongside surgical resection and liver transplantation. However, trans-arterial chemo-embolisation (TACE) is commonly used in the real-world as an initial treatment in patients with single small HCC in contrast to widely accepted clinical practice guidelines which typically describe TACE as a treatment for intermediate-stage HCC. We performed this real-world propensity-matched multi-centre cohort study in patients with single HCC ≤ 3 cm to assess for differences in survival outcomes between those undergoing initial TACE and those receiving upfront ablation. Patients with a new diagnosis of BCLC 0/A HCC with a single tumour ≤3 cm first diagnosed between 1 January 2016 and 31 December 2020 who received initial TACE or ablation were included in the study. A total of 348 patients were included in the study, with 147 patients receiving initial TACE and 201 patients undergoing upfront ablation. After propensity score matching using key covariates, 230 patients were available for analysis with 115 in each group. There were no significant differences in overall survival (log-rank test p = 0.652) or liver-related survival (log-rank test p = 0.495) over a median follow-up of 43 months. While rates of CR were superior after ablation compared to TACE as a first treatment (74% vs. 56%, p < 0.004), there was no significant difference in CR rates when allowing for further subsequent treatments (86% vs. 80% p = 0.219). In those who achieved CR, recurrence-free survival and local recurrence-free survival were similar (log rank test p = 0.355 and p = 0.390, respectively). Our study provides valuable real-world evidence that TACE when offered with appropriate follow-up treatment is a reasonable initial management strategy in very early/early-stage HCC, with similar survival outcomes as compared to those managed with upfront ablation. Further work is needed to better define the role for TACE in BCLC 0/A HCC.

Charged Gold Nanoparticles for Target Identification-Alignment and Automatic Segmentation of CT Image-Guided Adaptive Radiotherapy in Small Hepatocellular Carcinoma

Because of the challenges posed by anatomical uncertainties and the low resolution of plain computed tomography (CT) scans, implementing adaptive radiotherapy (ART) for small hepatocellular carcinoma (sHCC) using artificial intelligence (AI) faces obstacles in tumor identification-alignment and automatic segmentation. The current study aims to improve sHCC imaging for ART using a gold nanoparticle (Au NP)-based CT contrast agent to enhance AI-driven automated image processing. The synthesized charged Au NPs demonstrated notable in vitro aggregation, low cytotoxicity, and minimal organ toxicity. Over time, an in situ sHCC mouse model was established for in vivo CT imaging at multiple time points. The enhanced CT images processed using 3D U-Net and 3D Trans U-Net AI models demonstrated high geometric and dosimetric accuracy. Therefore, charged Au NPs enable accurate and automatic sHCC segmentation in CT images using classical AI models, potentially addressing the technical challenges related to tumor identification, alignment, and automatic segmentation in CT-guided online ART.

Hepatocellular Carcinoma: The Evolving Role of Systemic Therapies as a Bridging Treatment to Liver Transplantation

Hepatocellular carcinoma (HCC) is the third most common cause of cancer-related deaths. Classically, liver transplantation (LT) can be curative for HCC tumors within the Milan criteria. Bridging strategies to reduce the dropouts from LT waiting lists and/or to downstage patients who are beyond the Milan criteria are widely utilized. We conducted a literature-based review to evaluate the role of systemic therapies as a bridging treatment to liver transplantation (LT) in HCC patients. Tyrosine kinase inhibitors (TKIs) can be used as a systemic bridging therapy to LT in patients with contraindications for locoregional liver-directed therapies. Immune checkpoint inhibitor (ICI) treatment can be utilized either as a monotherapy or as a combination therapy with bevacizumab or TKIs prior to LT. Acute rejection after liver transplantation is a concern in the context of ICI treatment. Thus, a safe ICI washout period before LT and cautious post-LT immunosuppression strategies are required to reduce post-LT rejections and to optimize clinical outcomes. Nevertheless, prospective clinical trials are needed to establish definitive conclusions about the utility of systemic therapy as a bridging modality prior to LT in HCC patients.

Lymphocyte-to-C Reactive Protein Ratio is an Independent Predictor of Survival Benefits for Hepatocellular Carcinoma Patients Receiving Radiotherapy

Background

Stereotactic body radiotherapy (SBRT) has emerged as an alternative approach for patients with hepatocellular carcinoma (HCC), and we aim to find potential prognostic biomarkers for HCC patients who received SBRT.

Methods

In this study, we retrospectively analyzed HCC patients who underwent SBRT in our institution from January 2018 to December 2022. The inflammatory parameters, along with baseline patients' characteristics were collected to elucidate the potential relationship with survival benefits and liver toxicities.

Results

Overall, 35 patients were enrolled in our study. For the efficacy population (25 patients who underwent SBRT for primary liver lesions), the objective response rate (ORR) and disease control rate (DCR) were 60% and 100%, respectively. The median progression-free survival (PFS) was 9.9 months [95% confidence interval (CI) 5.6-14.1 months], and the median overall survival (OS) was 18.5 months (95% CI 14.2-22.8 months). We further confirmed that higher baseline lymphocyte-C-reactive protein ratio (LCR) (≥2361.11) was positively related to both longer PFS (12.0 vs 4.3 months, P = 0.002) and OS (21.9 vs 11.4 months, P = 0.022). Moreover, patients with diabetes and higher alpha-fetoprotein (AFP) (≥400 ng/mL) were also found to be associated with worse OS. The most common hepatotoxicity was elevated gamma-glutamyl transferase (GGT) (84.0%).

Conclusion

In conclusion, for patients with inoperable HCC, SBRT resulted in satisfactory local control, survival benefits, and acceptable liver toxicity. Pre-radiotherapy LCR might be an independent and readily available predictor for survival, which facilitates us to find the most appropriate treatment options.

Large hepatocellular carcinoma treated with sequential SBRT and immunotherapy with anti-VEGF (Vascular Endothelial Growth Factor) therapy

Managing large solitary hepatocellular carcinoma (HCC) remains challenging as guidelines recommend a palliative approach given the general poor prognosis without accounting for variations in the underlying tumour biology. Surgical resection provides significantly better survival than other modalities for HCC, but only a small proportion of patients with large tumours qualify for surgical resection. Recently, with technological advances in radiation therapy, stereotactic body radiation therapy (SBRT) has emerged as an alternative treatment option for HCC . In this paper, we present a patient who was diagnosed with a 13 cm HCC with vascular invasion. SBRT was delivered as a locoregional therapy followed by immunotherapy with the outcome of complete pathological response observed on right hemi-hepatectomy.

Chemoembolization Plus Ablation: Current Status

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related death worldwide. The treatment landscape for HCC has evolved significantly over the past decade, with several modalities available to treat various stages of disease. The Barcelona Clinic Liver Cancer (BCLC) system provides a foundation for treatment guidance. However, given the complex nature of HCC, a more nuanced approach is often required, especially for lesions sized between 3 and 5 cm. This review aims to analyze the available treatments for early-stage HCC lesions between 3 and 5 cm, with a focus on the therapeutic potential and efficacy of transarterial chemoembolization (TACE)-ablation. Additional therapies including TACE, ablation, transarterial radioembolization, and surgical resection are also reviewed and compared with TACE-ablation. TACE-ablation is a viable therapeutic option for early-stage HCC lesions between 3 and 5 cm. Surgical resection remains the gold standard. Although recent studies suggest radiation segmentectomy may be a curative approach for this patient population, further studies are needed to compare the relative efficacies between TACE-ablation and radiation segmentectomy.

Consensus report from the 10th global forum for liver magnetic resonance imaging: multidisciplinary team discussion

The 10th Global Forum for Liver Magnetic Resonance Imaging was held in October 2021. The themes of the presentations and discussions at this Forum are described in detail in the review by Taouli et al (2023). The focus of this second manuscript developed from the Forum is on multidisciplinary tumor board perspectives in hepatocellular carcinoma (HCC) management: how to approach early-, mid-, and late-stage management from the perspectives of a liver surgeon, an interventional radiologist, and an oncologist. The manuscript also includes a panel discussion by multidisciplinary experts on three selected cases that explore challenging aspects of HCC management. CLINICAL RELEVANCE STATEMENT: This review highlights the importance of a multidisciplinary team approach in liver cancer patients and includes the perspectives of a liver surgeon, an interventional radiologist, and an oncologist, including illustrative case studies. KEY POINTS: • A liver surgeon, interventional radiologist, and oncologist presented their perspectives on the treatment of early-, mid-, and late-stage HCC. • Different perspectives on HCC management between specialties emphasize the importance of multidisciplinary tumor boards. • A multidisciplinary faculty discussed challenging aspects of HCC management, as highlighted by three case studies.

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.

Effect of radiation fractionation on IDO1 via the NF-κB/COX2 axis in non-small cell lung cancer

Radiotherapy (RT) is the mainstay treatment modality for lung cancer. We recently reported that conventionally fractionated radiotherapy (CRT) with daily fractionation of 2Gy significantly increased the activity of indoleamine 2,3-dioxygenase (IDO1), a known immune checkpoint, which predicted poorer long-term survival in patients with non-small cell lung cancer (NSCLC), while stereotactic body radiotherapy (SBRT) using fractionation size of 10Gy did not increase IDO1 activity and had better survival. Here we hypothesized that the hypofractionated SBRT kind of dose fraction stimulates host antitumor immunity via downregulating IDO1 in which CRT could not. We tested this hypothesis in vitro and in vivo using 10Gyx1 and 2Gyx8 fractionations in the laboratory. The results demonstrated that, although there was an initial downregulation after RT, the expression of IDO1 was ultimately upregulated by both fractionation regimens. The 10Gyx1 regimen had minimum upregulation, while the 2Gyx8 regimen significantly increased in IDO1 expression which was positively correlated with the elevated expressions of p-NF-κB and COX2. Pharmacological inhibition of COX2 abolished RT-induced IDO1 expression. Furthermore, the IDO1 inhibitor, D-1-methyl-tryptophan (D-1MT), exerted RT-related tumor-killing effects in the NSCLC cell lines and mouse models. These findings suggest that, in addition to being an immune suppressor, IDO1 may serve as an adaptive resistance factor in RT. Furthermore, an unappreciated mechanism may exist, where a larger fraction size might be superior to conventional sizes in cancer treatment. This study may provide a rationale for future research in using IDO1 as a biomarker to personalize RT dose fractionation and COX2 inhibitor to decrease radiation immune suppression from CRT.

Hepatocellular Carcinoma: Surveillance, Diagnosis, Evaluation and Management

Hepatocellular carcinoma (HCC) ranks fourth in cancer-related deaths worldwide. Semiannual surveillance of the disease for patients with cirrhosis or hepatitis B virus allows for early detection with more favorable outcomes. The current underuse of surveillance programs demonstrates the need for intervention at both the patient and provider level. Mail outreach along with navigation provision has proven to increase surveillance follow-up in patients, while provider-targeted electronic medical record reminders and compliance reports have increased provider awareness of HCC surveillance. Imaging is the primary mode of diagnosis in HCC with The Liver Imaging Reporting and Data System (LI-RADS) being a widely accepted comprehensive system that standardizes the reporting and data collection for HCC. The management of HCC is complex and requires multidisciplinary team evaluation of each patient based on their preference, the state of the disease, and the available medical and surgical interventions. Staging systems are useful in determining the appropriate intervention for HCC. Early-stage HCC is best managed by curative treatment modalities, such as liver resection, transplant, or ablation. For intermediate stages of the disease, transarterial local regional therapies can be applied. Advanced stages of the disease are treated with systemic therapies, for which there have been recent advances with new drug combinations. Previously sorafenib was the mainstay systemic treatment, but the recent introduction of atezolizumab plus bevacizumab proves to have a greater impact on overall survival. Although there is a current lack of improved outcomes in Phase III trials, neoadjuvant therapies are a potential avenue for HCC management in the future.

Efficacy and safety of epigallocatechin-3-gallate in treatment acute severe dermatitis in patients with cancer receiving radiotherapy: a phase I clinical trial

To evaluate the safety and effectiveness of epigallocatechin-3-gallate (EGCG) solution treating the acute severe dermatitis in patients receiving radiotherapy. This phase I research enrolled patients with thoracic cancer receiving radiotherapy at Shandong Cancer Hospital and Institute in Shandong, China. EGCG solution was sprayed to the radiation field when grade III radiation-induced dermatitis (RID) first appearance. EGCG concentration escalated from 660 to 2574 μmol/L using modified-Fibonacci dose-escalation. RID and related symptoms were followed up every day. Between March 2021 and November 2021, 19 patients were enrolled in this phase I research. The median dose of grade III RID first observation was 44 Gy (30.6-52 Gy). As the EGCG treatment was performed continuously, all these grade III RID reactions were significantly decreased to grade I or grade II RID at three days after use of EGCG (p < 0.001). Significant relief can be observed in burning sensation (p < 0.001), tractive sensation (p < 0.001), tenderness (p < 0.001), erythema (p < 0.001), itching (p < 0.001) and pain (p < 0.001) after 15 days of EGCG treatment. No radiation therapy delay or interruption for all 19 patients. No adverse events were observed and reported associated with EGCG. The highest dose of this Phase I trial (2574 μmol/L) was recommended for continuous Phase II trial for further evaluation. In this phase I clinical research, use of EGCG solution is safe and can significantly relief grade III RID in patients receiving radiotherapy. Thus, EGCG might be a new choice for acute sever RID.Trial Registration: ClinicalTrials.gov Identifier: NCT02580279 (Full date of first registration: 12/2014).

A propensity score matching study on survival benefits of radiotherapy in patients with inoperable hepatocellular carcinoma

With the advancements in radiotherapy (RT) in recent years, several studies have shown that RT can significantly prolong the survival of patients with hepatocellular carcinoma (HCC). As a noninvasive treatment option, the application of RT for the treatment of HCC is garnering increasing attention. In this retrospective study, we included data from 13,878 patients with HCC from the Surveillance, Epidemiology, and End Results (SEER) database between 2000 and 2019 and 325 patients with HCC treated in three tertiary hospitals in China between 2015 and 2021. Patient data were divided into RT and non-RT groups based on whether the patients underwent RT. Propensity score matching analysis was performed to minimize the deviation between the RT and non-RT groups, and the Kaplan-Meier method, Cox proportional hazard model, and nomogram were used to assess the efficacy of undergoing RT. The median overall survival (mOS) of the RT group was significantly longer compared with that of the non-RT group for the SEER data (16 months versus 9 months, p < 0.01). Similarly, the survival benefit was more significant in the RT group than in the non-RT group at our hospitals (34.1 months versus 15.4 months, p < 0.01). Furthermore, multivariate Cox analysis revealed that factors, including tumor (T) stage, patient age, tumor grade, serum AFP level, and chemotherapy, also affected patient survival. Moreover, these factors were also used to construct a nomogram. Subgroup analysis of these factors showed that RT was effective in prolonging patient survival in different populations. RT significantly improves the survival time of patients with inoperable HCC, thereby providing a basis for selecting HCC patients who can benefit from RT.

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.

Metastasis of Hepatocellular Carcinoma in the Pouch of Douglas Successfully Treated by Radiation Therapy: A Case Report

Metastasis of hepatocellular carcinoma (HCC) in the pouch of Douglas is relatively rare. A 65-year-old man with liver cirrhosis was admitted for detailed examination of a pelvic tumor. He had a previous history of ruptured HCC, and received emergent hemostasis with transcatheter arterial embolization followed by curative ablation. His blood tests showed an increase in des-gamma-carboxy prothrombin (DCP). Contrast-enhanced computed tomography (CE-CT) revealed a heterogeneously enhanced large pelvic tumor, but no additional tumorous lesions were detected in other organs, including the lungs, liver and abdominal lymph nodes. The colonoscopy showed compression by an extra-luminal/submucosal tumor, and computed tomography-guided percutaneous needle biopsy revealed that the pelvic tumor was metastasis of HCC. Because of the poor liver function, the solitary pelvic tumor was treated with three-dimensional conformal radiation therapy (3D-CRT). The tumor size and the DCP value were markedly decreased after radiation therapy. Nine months later, occasional mild bloody stool due to radiation proctitis was observed; however, no serious side effects occurred. Our case suggests that radiation therapy may be a therapeutic option for a solitary metastatic lesion of HCC in the pouch of Douglas.

Proton liver stereotactic body radiation therapy: Treatment techniques and dosimetry feasibility from a single institution

Purpose

To assess the resulting dosimetry characteristics of simulation and planning techniques for proton stereotactic body radiation therapy (SBRT) of primary and secondary liver tumors.

Methods

Consecutive patients treated under volumetric daily image guidance with liver proton SBRT between September 2019 and March 2022 at Emory Proton Therapy Center were included in this study. Prescriptions ranged from 40 Gy to 60 Gy in 3- or 5-fraction regimens, and motion management techniques were used when target motion exceeded 5 mm. 4D robust optimization was used when necessary. Dosimetry evaluation was conducted for ITV V100, D99, Dmax, and liver-ITV mean dose and D700cc. Statistical analysis was performed using independent-samples Mann-Whitney U tests.

Results

Thirty-six tumors from 29 patients were treated. Proton therapy for primary and secondary liver tumors using motion management techniques and robust optimization resulted in high target coverage and low doses to critical organs. The median ITV V100% was 100.0%, and the median ITV D99% was 111.3%. The median liver-ITV mean dose and D700cc were 499 cGy and 5.7 cGy, respectively. The median conformity index (CI) was 1.03, and the median R50 was 2.56. Except for ITV D99% (primary 118.1% vs. secondary 107.2%, p = 0.005), there were no significant differences in age, ITV volume, ITV V100%, ITV maximum dose, liver-ITV mean dose, or D700cc between primary and secondary tumor groups.

Conclusion

The study demonstrated that proton therapy with motion management techniques and robust optimization achieves excellent target coverage with low normal liver doses for primary and secondary liver tumors. The results showed high target coverage, high conformality, and low doses to the liver.

Selecting the Best Approach for the Treatment of Multiple Non-Metastatic Hepatocellular Carcinoma

According to the Barcelona Clinic Liver Cancer (BCLC) staging system, the optimal strategy for patients with multiple HCC within the Milan Criteria is liver transplantation (LT). However, LT cannot be offered to all the patients due to organ shortages and long waiting lists, as well as because of the advanced disease carrying a high risk of poor outcomes. For early stages, liver resection (LR) or thermal ablation (TA) can be proposed, while trans-arterial chemoembolization (TACE) still remains the treatment of choice for intermediate stages (BCLC-B). Asian guidelines and the National Comprehensive Cancer Network suggest LR for resectable multinodular HCCs, even beyond Milan criteria. In this scenario, a growing body of evidence shows better outcomes after surgical resection when compared with TACE. Trans-arterial radioembolization (TARE) and stereotaxic body radiation therapy (SBRT) can also play an important role in this setting. Furthermore, the role of minimally invasive liver surgery (MILS) specifically for patients with multiple HCC is still not clear. This review aims to summarize current knowledge about the best therapeutical strategy for multiple HCC while focusing on the role of minimally invasive surgery and on the most attractive future perspectives.

Role of Functional MRI in Liver SBRT: Current Use and Future Directions

Stereotactic body radiation therapy (SBRT) is an emerging treatment for liver cancers whereby large doses of radiation can be delivered precisely to target lesions in 3-5 fractions. The target dose is limited by the dose that can be safely delivered to the non-tumour liver, which depends on the baseline liver functional reserve. Current liver SBRT guidelines assume uniform liver function in the non-tumour liver. However, the assumption of uniform liver function is false in liver disease due to the presence of cirrhosis, damage due to previous chemo- or ablative therapies or irradiation, and fatty liver disease. Anatomical information from magnetic resonance imaging (MRI) is increasingly being used for SBRT planning. While its current use is limited to the identification of target location and size, functional MRI techniques also offer the ability to quantify and spatially map liver tissue microstructure and function. This review summarises and discusses the advantages offered by functional MRI methods for SBRT treatment planning and the potential for adaptive SBRT workflows.