Three-dimensional conformal radiotherapy for portal vein tumor thrombosis alone in advanced hepatocellular carcinoma

Radiation and Immune Checkpoint Inhibitors: Combination Therapy for Treatment of Hepatocellular Carcinoma

The liver tumor immune microenvironment has been thought to possess a critical role in the development and progression of hepatocellular carcinoma (HCC). Despite the approval of immune checkpoint inhibitors (ICIs), such as programmed cell death receptor 1 (PD-1)/programmed cell death ligand 1 (PD-L1) and cytotoxic T lymphocyte associated protein 4 (CTLA-4) inhibitors, for several types of cancers, including HCC, liver metastases have shown evidence of resistance or poor response to immunotherapies. Radiation therapy (RT) has displayed evidence of immunosuppressive effects through the upregulation of immune checkpoint molecules post-treatment. However, it was revealed that the limitations of ICIs can be overcome through the use of RT, as it can reshape the liver immune microenvironment. Moreover, ICIs are able to overcome the RT-induced inhibitory signals, effectively restoring anti-tumor activity. Owing to the synergetic effect believed to arise from the combination of ICIs with RT, several clinical trials are currently ongoing to assess the efficacy and safety of this treatment for patients with HCC.

Non-Surgical Locoregional Therapies Alone or in Combination with Systemic Therapy in Patients with Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the most common primary liver cancer, representing the third-leading cause of cancer-related deaths worldwide. Curative intent treatment options for patients with HCC include liver transplantation, resection and ablation of small lesions. Other potentially curative therapies include cryoablation, microwave ablation and percutaneous alcohol injection. For locally advanced disease, different arterially directed therapies including transarterial chemoembolization and selective internal radiation therapy, plus external beam radiation including three-dimensional conformal radiation therapy, intensity-modulated radiation therapy, stereotactic body radiation therapy and proton beam therapy, are available or studied. Systemic therapies based on checkpoint inhibitors and tyrosine kinase inhibitors are available for the management of metastatic HCC and sometimes for locally advanced disease. Combinations of locoregional therapies with systemic drugs are currently the subject of several clinical trials.

Trends in radiotherapy administration in the management of hepatocellular carcinoma: Analysis of a Korean tertiary hospital registry of hepatocellular carcinoma patients diagnosed between 2005 and 2017

Purpose

To present the trends in radiotherapy for the management of hepatocellular carcinoma (HCC) at a single tertiary referral hospital in South Korea.

Materials and Methods

We retrospectively reviewed prospectively collected registry data of patients newly diagnosed with HCC between January 2005 and December 2017 at the Samsung Medical Center. Trends in radiotherapy, delivery techniques, tumor stage, and age were evaluated.

Results

During the study period, 9,132 patients were newly diagnosed with HCC at our institution. Of these, 2,445 patients (26.8%) received radiotherapy for all lesions, including extrahepatic metastases; 1,865 patients (20.4%) received radiotherapy for intrahepatic lesions alone, and 469 patients (5.1%) received radiotherapy as initial management. Although the proportion of patients receiving radiotherapy increased slightly over the study period (24.2% vs. 26.6%), the proportions of patients receiving radiotherapy for intrahepatic lesions (16.8% vs. 21.9%) and as initial management (0.1% vs. 12.5%) increased dramatically. The majority of patients treated between 2005 and 2008 received three-dimensional conformal radiotherapy (56.3%), whereas the majority of patients treated between 2018 and 2021 received proton beam therapy (43.6%). With the technical developments, the overall survival (OS) of patients who received radiotherapy as initial management increased significantly (5-year OS: from 5.4% to 30.1%), and the OS difference between patients who did and did not receive radiotherapy as initial management significantly decreased (ratio of restricted mean survival time: from 0.383 to 0.544).

Conclusion

This registry-based, retrospective study indicated an increasing trend in the utilization of radiotherapy, adoption of advanced radiotherapy techniques, and OS improvements in patients with HCC.

Is hepatocellular carcinoma complicated with portal vein tumor thrombosis potentially curable by radiotherapy in the form of stereotactic body radiation therapy?

PURPOSE

The prognosis of hepatocellular carcinoma (HCC) with portal vein tumor thrombosis (PVTT) is dismal. Despite best treatment and care, the patients with this malignancy only showed 2.7-4 months of overall survival. It is debatable whether liver transplantation helps PVTT sufferers. The effectiveness of radiation therapy in treating HCC patients with PVTT should not be undervalued. By limiting the high dosage region to a small planning target volume, stereotactic radiation delivery has shifted toward hypofractionation, limiting the radiation exposure to healthy organs and tissues. Stereotactic body radiotherapy (SBRT) has a local control rate of 75-100%, depending on the treatment. The major limitation in SBRT for hepatocellular carcinoma with PVTT is the paucity of prospective evidence for longer periods beyond the first two years after treatment. More prospective studies/randomized clinical trials with a longer follow-up, larger sample size, and adequate statistical power are the dire need of the present situation to ascertain the curative effect of SBRT as primary therapy for advanced HCC with PVTT.

CONCLUSION

SBRT can improve survival, particularly for patients receiving multidisciplinary treatment. This review sums up our most current understanding of how radiation therapy, notably SBRT, can be used to treat hepatocellular carcinoma when combined with PVTT. Recent research has led us to believe that irradiation in the form of SBRT may cure hepatocellular carcinoma complicated by PVTT.

MRI-guided radiotherapy for PVTT in HCC patients: evaluation of the efficacy and safety

PURPOSE

This study aims to evaluate the efficacy, feasibility, and safety of the magnetic resonance imaging (MRI)-guided tumor tracking hypofractionated radiotherapy (HFRT) and stereotactic body radiation therapy (SBRT) for portal vein tumor thrombus (PVTT) in hepatocellular carcinoma (HCC) patients.

METHODS

We retrospectively reviewed the twelve cases of unresectable HCC with tumor thrombus in the main trunk or first branch of the portal vein that were treated with MRI-guided tumor tracking HFRT or SBRT using the ViewRay Linac MRIdian system between June 2019 and January 2021. The HFRT was performed with a total of 50 Gy in 10 fractions, and SBRT performed in a range of 36-50 Gy with 4-5 fractions. The median biologic effective dose (BED) with an a/b ratio of 10 was 75 Gy₁₀ (range 68.4-100 Gy₁₀).

RESULTS

The median follow-up duration was 5.0 months (range 1.9-12.8 months). Ten patients (83.3%) showed an objective response of PVTT. At the time of analysis, ten patients (83.3%) showed local control. The 1-year intrahepatic control rate was 48.9%. Three patients (25%) showed mild gastrointestinal symptoms, and there were no cases of grade 3 or higher toxicity. For hepatic toxicity, there were no cases in which the Child-Pugh score increased by more than two points after RT without disease progression.

CONCLUSION

MRI-guided tumor tracking HFRT and SBRT was a feasible, effective, and safe treatment option in HCC patients with tumor thrombi in the main trunk or first branch of the portal vein.

A novel classification of portal venous tumor invasion to predict residual tumor status after surgery in patients with pancreatic neuroendocrine neoplasms

PURPOSE

To elucidate whether portal venous tumor invasion (PVTI) is a prognostic factor for patients with pancreatic neuroendocrine neoplasms (Pan-NENs).

METHODS

From 2002 to 2019, 240 patients with Pan-NEN were included to examine prognostic factors. PVTI based on computed tomography (CT) images are classified into four types: no PVTI (Vp0/1), PVTI not invading the superior mesenteric vein (Vp2), PVTI invading the superior mesenteric vein or portal vein (Vp3), and PVTI invading the portal bifurcation (Vp4).

RESULTS

Simultaneous liver metastases (SLM) determined the overall survival (OS) in 240 patients. The 5-year OS rates with and without SLM were 46% and 92%, respectively (P < 0.001). PVTIs were observed in 56 of the 240 patients (23%). Among such patients, 39, 11, and 6 had Vp2, Vp3, and Vp4, respectively. The 5-year OS rates with and without PVTI were 62% and 82%, respectively (P < 0.001). Severity of PVTI did not decide PFS and OS after R0/1 resection. There was significant difference in the prognoses between Vp0/1 and Vp2-4. In 161 patients without SLM, 21 had PVTI (13%). According to a multivariate analysis, PVTI and Ki-67 index were independent prognostic factors for progression-free survival (PFS) in patients without SLM. The 5-year PFS rates with and without PVTI were 18% and 77%, respectively (P < 0.001). The 5-year OS rates with and without PVTI were 76% and 95%, respectively (P = 0.02). PVTI was associated with tumor functionality, high serum NSE, and high Ki-67 index.

CONCLUSIONS

PVTI may be a predictor for postoperative recurrence.

Effectiveness of stereotactic body radiotherapy for portal vein tumor thrombosis in patients with hepatocellular carcinoma and underlying chronic liver disease

AIM

Stereotactic-body radiotherapy (SBRT) is a treatment option for portal vein tumor thrombosis (PVTT) in patients with hepatocellular carcinoma (HCC). Here, we report on our experience of treating PVTT using SBRT in patients with concomitant underlying chronic liver disease.

METHODS

This study included 24 patients. The initial prescription dose was 45 Gy in three fractions in 17 (70.8%) patients, but it was modified in the remaining seven (29.2%) patients, with the dose ranging from 39 to 42 Gy in 3-4 fractions. After SBRT, transarterial chemoembolization (TACE) was performed in 16 (66.7%) patients.

RESULTS

Of the 24 patients, 2 (8.3%) showed complete response, while 11 (45.8%) showed partial response. After a median follow-up of 8.4 months (range: 2.6-56.5 months), the 1-year overall survival (OS) and the median survival were 67.5% and 20.8 months, respectively. Both combined SBRT and TACE and grade ≥3 hepatic toxicity affected the 1-year OS (SBRT alone vs SBRT + TACE: 14.6% vs 71.4%, P < .001; presence of hepatic toxicity vs absence: 0% vs 81.1%, P = .002).

CONCLUSIONS

Overall, SBRT, especially in combination with TACE, is an effective treatment for patients with HCC and PVTT. An optimal dose schedule must be followed to reduce hepatic toxicity while maintaining tumor response.

Suitability of boric acid as a boron drug for boron neutron capture therapy for hepatoma

Hepatoma is the second leading cause of cancer death worldwide. Due to the poor outcomes of patients with late diagnosis, newer treatments for hepatoma are still needed. As an emerging therapy, boron neutron capture therapy (BNCT) may be an effective solution in hepatoma management. In this study, boric acid (BA) was used as the boron drug for in vivo analysis of action mechanism. The N1S1 single liver tumor-bearing rat and the VX2 multifocal liver tumor-bearing rabbit models were used to investigate the retention status of BA in the tumor regions during BNCT. The autoradiographic examination showed BA can localize specifically not only in the hepatoma cells but also in tumor blood vessels. Our findings indicate that superior hepatoma targeting could be achieved in BA-mediated BNCT, which supports BA to be a suitable boron drug for BNCT for hepatoma.

Treatment of hepatocellular carcinoma in patients with portal vein tumor thrombosis: Beyond the known frontiers

Hepatocellular carcinoma is one of the most frequent malignant tumors worldwide: Portal vein tumor thrombosis (PVTT) occurs in about 35%-50% of patients and represents a strong negative prognostic factor, due to the increased risk of tumor spread into the bloodstream, leading to a high recurrence risk. For this reason, it is a contraindication to liver transplantation and in several prognostic scores sorafenib represents its standard of care, due to its antiangiogenetic action, although it can grant only a poor prolongation of life expectancy. Recent scientific evidences lead to consider PVTT as a complex anatomical and clinical condition, including a wide range of patients with different prognosis and new treatment possibilities according to the degree of portal system involvement, tumor biological aggressiveness, complications caused by portal hypertension, patient's clinical features and tolerance to antineoplastic treatments. The median survival has been reported to range between 2.7 and 4 mo in absence of therapy, but it can vary from 5 mo to 5 years, thus depicting an extremely variable scenario. For this reason, it is extremely important to focus on the most adequate strategy to be applied to each group of PVTT patients.

Combined Yttrium-90 microsphere selective internal radiation therapy and external beam radiotherapy in patients with hepatocellular carcinoma: From clinical aspects to dosimetry

Purpose

Selective internal radiation therapy (SIRT) is an effective treatment strategy for unresectable hepatocellular carcinoma (HCC) patients. However, the prognoses of patients with portal vein thrombosis, extra-hepatic metastases, or residual tumors remain poor when treated with SIRT alone. In these patients, sequential external beam radiotherapy (EBRT) may offer a chance of salvage. Here, we reported the clinical outcomes and the detailed dosimetry analysis of 22 patients treated with combination therapy.

Methods

Between October 2011 and May 2015, 22 consecutive patients who underwent EBRT after yttrium-90 (⁹⁰Y) SIRT were included in this study. The post-SIRT ⁹⁰Y bremsstrahlung SPECT/CT of each patient was transferred to dose distribution by adopting the local deposition hypothesis. The patient-specific 3-dimensional biological effective dose distribution of combined SIRT and EBRT was generated. The overall survival and safety were evaluated. The relationship between dosimetric parameters and liver toxicity was analyzed.

Results

The mean administered activity of SIRT was 1.50 GBq (range: 0.5–2.8). The mean prescribed dose of EBRT was 42.3 Gy (range: 15–63) in 14 fractions (range: 5–15) and was targeted to the residual liver tumor in 12 patients (55%), portal vein thrombosis in 11 patients (50%), and perihilar lymphadenopathies in 4 patients (18%). The overall 1-, 2-, and 3-year survival rates were 59.8%, 47.9%, and 47.9%, respectively. Overall, 8 patients (36%) developed > grade 2 liver toxicities, and the Child-Pugh score prior to EBRT strongly affected the toxicity risk. A dosimetry analysis restricted to 18 Child-Pugh A/B patients showed that the V100 (The fraction of normal liver exposed to more than 100 Gy) to V140 significance differed between patients who did or did not experience hepatotoxicity. The V110 was the strongest predictor of hepatotoxicity (18.6±11.6% vs 29.5±5.8%; P = 0.030).

Conclusion

Combined therapy is feasible and safe if patients are carefully selected. Specifically, 3-dimensional dosimetry is crucial for the evaluation of efficacy and toxicity. The normal liver V100 to V140 values of the combined dose should be as low as possible to minimize the risk of liver toxicity.

Efficacy of External Beam Radiation-Based Treatment plus Locoregional Therapy for Hepatocellular Carcinoma Associated with Portal Vein Tumor Thrombosis

Background. Portal vein tumor thrombosis (PVTT) is a common event in advanced hepatocellular carcinoma (HCC). The optimal treatment for these patients remains controversial. Methods. A retrospective review of 149 patients who had unresectable HCC associated with PVTT between January 2005 and December 2012 was performed. Outcomes related to external beam radiation-based treatment were measured, and clinicopathological features and parameters affecting prognosis were analyzed as well. Results. The radiotherapeutic response of PVTT was an important element that affected the overall treatment response of HCC. Serum α-fetoprotein < 400 ng/mL, the presence of a radiotherapeutic response on PVTT, and receiving additional locoregional therapy were significant prognostic factors affecting the survival of patients. Patients who had received additional locoregional therapy obtained a better outcome, and six of them were eventually able to undergo surgical management with curative intent. Conclusion. The outcome of HCC associated with PVTT remains pessimistic. In addition to the current recommended treatment using sorafenib, a combination of external beam radiotherapy targeting PVTT and locoregional therapy for intrahepatic HCC might be a promising strategy for patients who had unresectable HCC with PVTT. This approach could perhaps offer patients a favorable outcome as well as a possible cure with following surgical management.

Management of hepatocellular carcinoma with portal vein tumor thrombosis: Review and update at 2016

Portal vein tumor thrombosis (PVTT) is a common phenomenon in hepatocellular carcinoma (HCC). Compared to HCC without PVTT, HCC with PVTT is characterized by an aggressive disease course, worse hepatic function, a higher chance of complications related to portal hypertension and poorer tolerance to treatment. Conventionally, HCC with PVTT is grouped together with metastatic HCC during the planning of its management, and most patients are offered palliative treatment with sorafenib or other systemic agents. As a result, most data on the management of HCC with PVTT comes from subgroup analyses or retrospective series. In the past few years, there have been several updates on management of HCC with PVTT. First, it is evident that HCC with PVTT consists of heterogeneous subgroups with different prognoses. Different classifications have been proposed to stage the degree of portal vein invasion/thrombosis, suggesting that different treatment modalities may be individualized to patients with different risks. Second, more studies indicate that more aggressive treatment, including surgical resection or locoregional treatment, may benefit select HCC patients with PVTT. In this review, we aim to discuss the recent conceptual changes and summarize the data on the management of HCC with PVTT.

The response of thrombosis in the portal vein or hepatic vein in hepatocellular carcinoma to radiation therapy

Purpose

The purpose of current study is to evaluate the response of the patients with portal vein thrombosis (PVT) or hepatic vein thrombosis (HVT) in hepatocellular carcinoma (HCC) treated with three-dimensional conformal radiation therapy (3D-CRT). In addition, survival of patients and potential prognostic factors of the survival was evaluated.

Materials and Methods

Forty-seven patients with PVT or HVT in HCC, referred to our department for radiotherapy, were retrospectively reviewed. For 3D-CRT plans, a gross tumor volume (GTV) was defined as a hypodense filling defect area in the portal vein (PV) or hepatic vein (HV). Survival of patients, and response to radiation therapy (RT) were analyzed. Potential prognostic factors for survival and response to RT were evaluated.

Results

The median survival time of 47 patients was 8 months, with 1-year survival rate of 15% and response rate of 40%. Changes in Child-Pugh score, response to RT, Eastern cooperative oncology group performance status (ECOG PS), hepatitis C antibody (HCVAb) positivity, and additional post RT treatment were statistically significant prognostic factors for survival in univariate analysis (p = 0.000, p = 0.018, p = 0.000, p = 0.013, and p = 0.047, respectively). Of these factors, changes in Child-Pugh score, and response to RT were significant for patients’ prognosis in multivariate analysis (p = 0.001 and p = 0.035, respectively).

Conclusion

RT could constitute a reasonable treatment option for patients with PVT or HVT in HCC with acceptable toxicity. Changes in Child-Pugh score, and response to RT were statistically significant factors of survival of patients.

Prognostic value of pretreatment (18)F-FDG PET-CT in radiotherapy for patients with hepatocellular carcinoma

Purpose

The purpose of this study was to investigate the predictable value of pretreatment ¹⁸F-fluorodeoxyglucose positron emission tomography-computed tomography (¹⁸F-FDG PET-CT) in radiotherapy (RT) for patients with hepatocellular carcinoma (HCC) or portal vein tumor thrombosis (PVTT).

Materials and Methods

We conducted a retrospective analysis of 36 stage I-IV HCC patients treated with RT. ¹⁸F-FDG PET-CT was performed before RT. Treatment target was determined HCC or PVTT lesions by treatment aim. They were irradiated at a median prescription dose of 50 Gy. The response was evaluated within 3 months after completion of RT using the Response Evaluation Criteria in Solid Tumors (RECIST). Response rate, overall survival (OS), and the pattern of failure (POF) were analyzed.

Results

The response rate was 61.1%. The statistically significant prognostic factor affecting response in RT field was maximal standardized uptake value (maxSUV) only. The high SUV group (maxSUV ≥ 5.1) showed the better radiologic response than the low SUV group (maxSUV < 5.1). The median OS were 996.0 days in definitive group and 144.0 days in palliative group. Factors affecting OS were the %reduction of alpha-fetoprotein (AFP) level in the definitive group and Child-Pugh class in the palliative group. To predict the POF, maxSUV based on the cutoff value of 5.1 was the only significant factor in distant metastasis group.

Conclusion

The results of this study suggest that the maxSUV of ¹⁸F-FDG PET-CT may be a prognostic factor for treatment outcome and the POF after RT. A %reduction of AFP level and Child-Pugh class could be used to predict OS in HCC.

Prognostic indicators for radiotherapy of abdominal lymph node metastases from hepatocellular carcinoma

PURPOSE

To identify prognostic indicators in patients treated with radiotherapy (RT) for metastases from hepatocellular carcinoma (HCC) in abdominal lymph nodes (LNs).

PATIENTS AND METHODS

RT was used to treat 65 patients for metastases from HCC in abdominal LNs. Total radiation dose was 30-60 Gy (median 52.8 Gy), with fraction size 1.8-3 Gy. RT was administered five times per week to an equivalent dose in 2-Gy fractions (EQD2; Gy10) of 32.5-65 Gy10 (median 54 Gy10) and an α/βratio for tumor and acute effects of normal tissue of 10.

RESULTS

Median overall survival (OS) in all patients was 8.1 months. LN responders had significantly higher median OS than nonresponders (14.5 vs. 3.7 months, p < 0.05). Multivariate analysis showed that Child-Pugh classification, status of intrahepatic tumor, number of metastatic LNs, and LN response were independently predictive of OS (p < 0.05 each). Based on results of multivariate analysis, patients were prognostically stratified according to pretreatment risk factors, including Child-Pugh classification, intrahepatic tumor status, and number of metastatic LNs; with the expected median OS in patients with ≥ 2, 1, and 0 risk factors being 2.9, 9.8, and 27.6 months, respectively (p < 0.05).

CONCLUSION

Our data showed that LN response to RT was an independent prognostic factor for OS in advanced HCC patients with abdominal LN metastases, and suggested that RT for metastatic LNs might improve OS in these patients. In addition, our data suggest that Child-Pugh classification, intrahepatic tumor status, and number of metastatic LNs may be useful prognostic and therapeutic indicators for selecting treatment strategies.

Management of hepatocellular carcinoma with portal vein thrombosis

Management of hepatocellular carcinoma (HCC) with portal vein thrombosis (PVT) is complex and requires an understanding of multiple therapeutic options. PVT is present in 10%-40% of HCC at the time of diagnosis, and is an adverse prognostic factor. Management options are limited, as transplantation is generally contraindicated, and surgical resection is only rarely performed in select centers. Systemic medical therapy with sorafenib has been shown to modestly prolong survival. Transarterial chemoembolization has been performed in select cases but has shown a high incidence of complications. Emerging data on treatment of PVT with Y-90 radioembolization suggest that this modality is well-tolerated and associated with favorable overall survival. Current society guidelines do not yet specifically recommend radioembolization for patients with PVT, but this may change with the development of newer staging systems and treatment algorithms. In this comprehensive literature review, we present current and available management options with the relative advantages, disadvantages and contraindications of these treatment options with summarized data on overall survival.