Selective internal radiation therapy for nonresectable hepatocellular carcinoma with intraarterial infusion of 90yttrium microspheres

Efficacy of Selective Internal Radiation Therapy for Hepatocellular Carcinoma Post-Incomplete Response to Chemoembolization

Hepatocellular carcinoma (HCC) is one of the most common neoplasms worldwide and the third most common cause of cancer-related death. Several liver-targeted intra-arterial therapies are available for unresectable HCC, including selective internal radiation therapy (SIRT) and trans-arterial chemoembolization (TACE). Those two are the most used treatment modalities in localized non-operable HCC. TACE is the treatment option for patients with stage B, according to the BCLC staging system. In contrast, SIRT does not have an official role in the treatment algorithm, but recent studies showed promising outcomes in patients treated with SIRT. Although TACE is globally a safe procedure, it might provoke several vascular complications such as spasms, inflammatory constriction, and, in severe cases, occlusion, dissection, or collateralization. Hence, it is acclaimed that those complications could restrain the targeted response of the radio-embolization when we use it as second-line therapy post TACE. In this study, we will assess the efficacity of SIRT using Yttrium 90 Microspheres post incomplete or failure response to TACE. In our retrospective study, we had 23 patients who met the inclusion criteria. Furthermore, those patients have been followed radiologically and biologically. Then, we evaluated the therapeutic effect according to the mRECIST criteria, in addition to the personalized dose analysis. We found 8 patients were treated with TheraSphere®, with a median tumor absorbed dose of 445 Gy, while 15 received SIR-Spheres® treatment with a mean tumor dose of 268 Gy. After radiological analysis, 56.5% of the patients had a complete response, and 17.3% showed partial response, whereas 13% had stable disease and 13% had progressive disease. For patients treated with SIRT after an incomplete response or failure to TACE, we found an objective response rate of 73.8%. Despite the known vascular complications of TACE, SIRT can give a favorable response.

The Current Status and Future Prospects for Conversion Therapy in the Treatment of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the third most common cause of cancer-related deaths worldwide. In China, most HCC patients are diagnosed with advanced disease and in these cases surgery is challenging. Conversion therapy can be used to change unresectable HCC into resectable disease and is a potential breakthrough treatment strategy. The resection rate for unresectable advanced HCC has recently improved as a growing number of patients have benefited from conversion therapy. While conversion therapy is at an early stage of development, progress in patient selection, optimum treatment methods, and the timing of surgery have the potential to deliver significant benefits. In this article, we review the current evidence and clinical experience of conversion therapy in HCC. General conversion modalities such as systemic treatments (systemic chemotherapy, targeted therapy, or immunotherapy), locoregional therapy (transarterial chemoembolization, hepatic arterial infusion chemotherapy, or selective internal radiation therapy), and combination therapy were summarized. We also discuss the current challenges of conversion therapy and provide identify areas for future research to improve the development of conversion therapy in advanced HCC.

Radiochemical Feasibility of Mixing of 99mTc-MAA and 90Y-Microspheres with Omnipaque Contrast

Yttrium-90 (90Y) microspheres are widely used for the treatment of liver-dominant malignant tumors. They are infused via catheter into the hepatic artery branches supplying the tumor under fluoroscopic guidance based on pre-therapy angiography and Technetium-99m macroaggregated albumin (99mTc-MAA) planning. However, at present, these microspheres are suspended in radiolucent media such as dextrose 5% (D5) solution. In order to monitor the real-time implantation of the microspheres into the tumor, the 90Y microspheres could be suspended in omnipaque contrast for allowing visualization of the correct distribution of the microspheres into the tumor. The radiochemical purity of mixing 90Y-microspheres in various concentrations of omnipaque was investigated. The radiochemical purity and feasibility of mixing 99mTc-MAA with various concentrations of a standard contrast agent were also investigated. Results showed the radiochemical feasibility of mixing 90Y-microspheres with omnipaque is radiochemically acceptable for allowing real-time visualization of radioembolization under fluoroscopy.

Efficacy of transarterial chemoembolization monotherapy or combination conversion therapy in unresectable hepatocellular carcinoma: A systematic review and meta-analysis

Background

Hepatocellular carcinoma (HCC) is a highly malignant disease with poor prognosis, and most cases were already considered unresectable at the time of presentation. Conversion therapy, as an emerging treatment, is designed to provide patients with initially unresectable hepatocellular carcinoma (uHCC) the opportunity to undergo radical resection. At present, conversion therapy for patients with uHCC remains controversial. Transarterial chemoembolization (TACE) is currently the most widely selected treatment for uHCC, but its efficacy as a conversion therapy remains controversial.

Methods

We compared and evaluated the conversion rate for and tumor response to TACE monotherapy or combination therapy. Meanwhile, postoperative complications and overall survival (OS) in uHCC patients who underwent conversion therapy were also analyzed.

Results

A total of 18 studies were included in this meta-analysis. The conversion rate for triple therapy [TACE in combination with tyrosine kinase inhibitors (TKIs) and immune checkpoint inhibitors (ICIs)] was 42% [95% confidence interval (CI), 0.29–0.56], higher than any other group [TACE monotherapy: 10% (95% CI, 0.08–0.12), bigeminy therapy: 19% (95% CI, 0.06–0.36)]. Meanwhile, triple therapy yielded a better tumor response than TACE monotherapy or bigeminy therapy. Among the patients with successful surgical resection after conversion therapy, the pooled postoperative OS rates at 1, 2, and 5 years were 90% (95% CI, 0.81–0.97), 58% (95% CI, 0.42–0.73), and 42% (95% CI, 0.26–0.60), respectively, and the major postoperative complications were biliary leakage (7%; 95% CI, 0.03–0.12) and liver failure (3%; 95% CI, 0.00–0.07).

Conclusion

TACE conversion therapies showed good conversion rates, especially the triple therapy of TACE in combination with TKIs and ICIs. Surgical resection after successful conversion therapy could maximize the outcome of patients with uHCC.

Individualization of Radionuclide Therapies: Challenges and Prospects

Simple Summary

Currently, patient-specific treatment plans and dosimetry calculations are not routinely performed for radionuclide therapies. In external beam radiotherapy, it is quite the opposite. As a result, a small fraction of patients receives optimal radioactivity. This conservative approach provides “radiation safety” to healthy tissues but delivers a lower than indicated absorbed dose to the tumors, resulting in a lower response rate and a higher disease relapse rate. Evidence shows that better and more predictable outcomes can be achieved with patient-individualized dose assessment. Therefore, the incorporation of individual planning into radionuclide therapies is a high priority for nuclear medicine physicians and medical physicists alike. Internal dosimetry is used in tumor therapy to optimize the absorbed dose to the target tissue. The main reasons for the difficulties in incorporating patients’ internal dosimetry into routine clinical practice are discussed. The article presents the prospects for the routine implementation of personalized radionuclide therapies.

Abstract

The article presents the problems of clinical implementation of personalized radioisotope therapy. The use of radioactive drugs in the treatment of malignant and benign diseases is rapidly expanding. Currently, in the majority of nuclear medicine departments worldwide, patients receive standard activities of therapeutic radiopharmaceuticals. Intensively conducted clinical trials constantly provide more evidence of a close relationship between the dose of radiopharmaceutical absorbed in pathological tissues and the therapeutic effect of radioisotope therapy. Due to the lack of individual internal dosimetry (based on the quantitative analysis of a series of diagnostic images) before or during the treatment, only a small fraction of patients receives optimal radioactivity. The vast majority of patients receive too-low doses of ionizing radiation to the target tissues. This conservative approach provides “radiation safety” to healthy tissues, but also delivers lower radiopharmaceutical activity to the neoplastic tissue, resulting in a low level of response and a higher relapse rate. The article presents information on the currently used radionuclides in individual radioisotope therapies and on radionuclides newly introduced to the therapeutic market. It discusses the causes of difficulties with the implementation of individualized radioisotope therapies as well as possible changes in the current clinical situation.

Clinical consensus statement: Selective internal radiation therapy with yttrium 90 resin microspheres for hepatocellular carcinoma in Asia

BACKGROUND

Hepatocellular carcinoma (HCC) is subject to different management approaches and guidelines according to Eastern and Western therapeutic algorithms. Use of selective internal radiation therapy (SIRT) with resin yttrium 90 microspheres for HCC has increased in Asia in recent years, without clearly defined indications for its optimal application. The objective of this systematic review and expert consensus statement is to provide guidance and perspectives on the use of SIRT among patients with HCC in Asia.

MATERIALS AND METHODS

A systematic literature review identified current publications on HCC management and SIRT recommendations. A group of 10 experts, representing stakeholder specialties and countries, convened between August 2020 and March 2021 and implemented a modified Delphi consensus approach to develop guidelines and indications for use of SIRT for HCC in Asia. Final recommendations were organized and adjudicated based on the level of evidence and strength of recommendation, per approaches outlined by the American College of Cardiology/American Heart Association and Oxford Centre for Evidence-Based Medicine.

RESULTS

The experts acknowledged a general lack of evidence relating to use of SIRT in Asia and identified as an unmet need the lack of phase 3 randomized trials comparing clinical outcomes and survival following SIRT versus other therapies for HCC. Through an iterative process, the expert group explored areas of clinical relevance and generated 31 guidance statements and a patient management algorithm that achieved consensus.

CONCLUSION

These recommendations aim to support clinicians in their decision-making and to help them identify and treat patients with HCC using SIRT in Asia. The recommendations also highlight areas in which further clinical trials are needed to define the role of SIRT in management of HCC among Asian populations.

Chinese expert consensus on conversion therapy for hepatocellular carcinoma (2021 edition)

Recent advances in systemic and locoregional treatments for patients with unresectable or advanced hepatocellular carcinoma (HCC) have resulted in improved response rates. This has provided an opportunity for selected patients with initially unresectable HCC to achieve adequate tumor downstaging to undergo surgical resection, a 'conversion therapy' strategy. However, conversion therapy is a new approach to the treatment of HCC and its practice and treatment protocols are still being developed. Review the evidence for conversion therapy in HCC and develop consensus statements to guide clinical practice. Evidence review: Many research centers in China have accumulated significant experience implementing HCC conversion therapy. Preliminary findings and data have shown that conversion therapy represents an important strategy to maximize the survival of selected patients with intermediate stage to advanced HCC; however, there are still many urgent clinical and scientific challenges for this therapeutic strategy and its related fields. In order to summarize and learn from past experience and review current challenges, the Chinese Expert Consensus on Conversion Therapy for Hepatocellular Carcinoma (2021 Edition) was developed based on a review of preliminary experience and clinical data from Chinese and non-Chinese studies in this field and combined with recommendations for clinical practice. Sixteen consensus statements on the implementation of conversion therapy for HCC were developed. The statements generated in this review are based on a review of clinical evidence and real clinical experience and will help guide future progress in conversion therapy for patients with HCC.

EANM procedure guideline for the treatment of liver cancer and liver metastases with intra-arterial radioactive compounds

Primary liver tumours (i.e. hepatocellular carcinoma (HCC) or intrahepatic cholangiocarcinoma (ICC)) are among the most frequent cancers worldwide. However, only 10-20% of patients are amenable to curative treatment, such as resection or transplant. Liver metastases are most frequently caused by colorectal cancer, which accounts for the second most cancer-related deaths in Europe. In both primary and secondary tumours, radioembolization has been shown to be a safe and effective treatment option. The vast potential of personalized dosimetry has also been shown, resulting in markedly increased response rates and overall survival. In a rapidly evolving therapeutic landscape, the role of radioembolization will be subject to changes. Therefore, the decision for radioembolization should be taken by a multidisciplinary tumour board in accordance with the current clinical guidelines. The purpose of this procedure guideline is to assist the nuclear medicine physician in treating and managing patients undergoing radioembolization treatment. PREAMBLE: The European Association of Nuclear Medicine (EANM) is a professional non-profit medical association that facilitates communication worldwide among individuals pursuing clinical and research excellence in nuclear medicine. The EANM was founded in 1985. These guidelines are intended to assist practitioners in providing appropriate nuclear medicine care for patients. They are not inflexible rules or requirements of practice and are not intended, nor should they be used, to establish a legal standard of care. The ultimate judgment regarding the propriety of any specific procedure or course of action must be made by medical professionals taking into account the unique circumstances of each case. Thus, there is no implication that an approach differing from the guidelines, standing alone, is below the standard of care. To the contrary, a conscientious practitioner may responsibly adopt a course of action different from that set out in the guidelines when, in the reasonable judgment of the practitioner, such course of action is indicated by the condition of the patient, limitations of available resources or advances in knowledge or technology subsequent to publication of the guidelines. The practice of medicine involves not only the science but also the art of dealing with the prevention, diagnosis, alleviation and treatment of disease. The variety and complexity of human conditions make it impossible to always reach the most appropriate diagnosis or to predict with certainty a particular response to treatment. Therefore, it should be recognised that adherence to these guidelines will not ensure an accurate diagnosis or a successful outcome. All that should be expected is that the practitioner will follow a reasonable course of action based on current knowledge, available resources and the needs of the patient to deliver effective and safe medical care. The sole purpose of these guidelines is to assist practitioners in achieving this objective.

Development of neutron-activated samarium-153-loaded polystyrene microspheres as a potential theranostic agent for hepatic radioembolization

PURPOSE

Hepatic radioembolization is an effective minimally invasive treatment for primary and metastatic liver cancers. Yttrium-90 [90Y]-labelled resin or glass beads are typically used as the radioembolic agent for this treatment; however, these are not readily available in many countries. In this study, novel samarium-153 oxide-loaded polystyrene ([153Sm]Sm2O3-PS) microspheres were developed as a potential alternative to 90Y microspheres for hepatic radioembolization.

METHODS

The [152Sm]Sm2O3-PS microspheres were synthesized using solid-in-oil-in-water solvent evaporation. The microspheres underwent neutron activation using a 1 MW open-pool research reactor to produce radioactive [153Sm]Sm2O3-PS microspheres via 152Sm(n,γ)153Sm reaction. Physicochemical characterization, gamma spectroscopy and in-vitro radionuclide retention efficiency were carried out to evaluate the properties and stability of the microspheres before and after neutron activation.

RESULTS

The [153Sm]Sm2O3-PS microspheres achieved specific activity of 5.04 ± 0.52 GBq·g-1 after a 6 h neutron activation. Scanning electron microscopy and particle size analysis showed that the microspheres remained spherical with an average diameter of ~33 μm before and after neutron activation. No long half-life radionuclide and elemental impurities were found in the samples. The radionuclide retention efficiencies of the [153Sm]Sm2O3-PS microspheres at 550 h were 99.64 ± 0.07 and 98.76 ± 1.10% when tested in saline solution and human blood plasma, respectively.

CONCLUSIONS

A neutron-activated [153Sm]Sm2O3-PS microsphere formulation was successfully developed for potential application as a theranostic agent for liver radioembolization. The microspheres achieved suitable physical properties for radioembolization and demonstrated high radionuclide retention efficiency in saline solution and human blood plasma.

Disease control and failure patterns of unresectable hepatocellular carcinoma following transarterial radioembolization with yttrium-90 microspheres and with/without sorafenib

BACKGROUND

Impressive survival outcome of our previous study in unresectable hepatocellular carcinoma (HCC) patients undergoing yttrium-90 glass microspheres transarterial radioembolization (TARE) with/without sorafenib according to individuals’ disease burden, i.e., intrahepatic tumor load (IHT) and adverse disease features (ADFs) might partly be confounded by other treatments and underlying hepatic function. Therefore, a dedicated study focusing on treatment response and assessment of failure patterns might be a way to improve treatment outcome in addition to patient selection based on the disease burden.

AIM

To assess the tumor response, disease control and patterns of disease progression following TARE with/without sorafenib in unresectable HCC patients.

METHODS

This retrospective study was conducted in successful TARE procedures with available pre- and post-treatment imaging studies (n = 169). Three treatment subgroups were (1) TARE only (TARE_alone) for IHT ≤ 50% without ADFs, i.e., macrovascular invasion, extrahepatic disease (EHD) and infiltrative/ill-defined HCC (n = 63); (2) TARE with sorafenib (TARE_sorafenib) for IHT > 50% and/or presence of ADFs (n = 81); and (3) TARE only for patients who could not receive sorafenib due to contraindication or intolerance (TARE_no_sorafenib) (n = 25). Objective response rate (ORR; consisted of complete response (CR) and partial response (PR)), disease control rate (DCR; consisted of CR, PR and stable disease) and failure patterns of treated, intrahepatic and extrahepatic sites were assessed using the modified response evaluation criteria in solid tumors. Time to progression (TTP) was calculated from TARE to the first radiologic progression at any site using Kaplan-Meier method. Identification of prognostic factors for TTP using the univariate Kaplan-Meier method and multivariate Cox proportional hazard model were performed in major population subgroups, TARE_alone and TARE_sorafenib.

RESULTS

The median radiologic follow-up time was 4.4 mo (range 0.5-48.8). In treated area, ORR was highest in TARE_sorafenib (53.1%), followed by TARE_alone (41.3%) and TARE_no_sorafenib (16%). In intrahepatic area, DCR remained highest in TARE_sorafenib (84%), followed by TARE_alone (79.4%) and TARE_no_sorafenib (44%). The overall DCR was highest in TARE_alone (79.4%), followed by TARE_sorafenib (71.6%) and TARE_no_sorafenib (40%). Dominant failure patterns were intrahepatic for both TARE_alone (44.5%) and TARE_sorafenib (38.4%). Extrahepatic progression was more common in TARE_sorafenib (32%) and TARE_no_sorafenib (40%) than in TARE_alone (12.7%). TTP was longest in TARE_alone (8.6 mo; 95%CI: 3.4-13.8), followed by TARE_sorafenib (5.1 mo; 95%CI: 4.0-6.2) and TARE_no_sorafenib (2.7 mo; 95%CI: 2.2-3.1). Pre-existing EHD (HR: 0.37, 95%CI: 0.24-0.56, P < 0.001) was a sole prognostic factor for TTP in TARE_sorafenib with no prognostic factor for TTP in TARE_alone.

CONCLUSION

TARE with/without sorafenib according to individuals’ disease burden provided DCR approximately 70% with intrahepatic progression as dominant failure pattern. Extrahepatic progression was more common in procedures with initially high disease burden.

Clinical Management of Liver Cancer in India and Other Developing Nations: A Focus on Radiation Based Strategies

Hepatocellular carcinoma (HCC) is a global killer with preponderance in Asian and African countries. It poses a challenge for successful management in less affluent or developing nations like India, with large populations and limited infrastructures. This review aims to assess the available options and future directions for management of HCC applicable to such countries. While summarizing current and emerging clinical strategies for detection, staging and therapy of the disease, it highlights radioisotope- and radioactivity-based strategies as part of an overall program. Using the widely accepted Barcelona Clinic Liver Cancer (BCLC) staging system as a base, it evaluates the applicability of different therapeutic approaches and their synergistic combination(s) in the context of a patient-specific dynamic results-based strategy. It distills the conclusions of multiple HCC management-focused consensus recommendations to provide a picture of clinical strategies, especially radiation-related approaches. Additionally, it discusses the logistical and economic feasibility of these approaches in the context of the limitations of the burdened public health infrastructure in India (and like nations) and highlights possible strategies both at the clinical level and in terms of an administrative health policy on HCC to provide the maximum possible benefit to the widest swathe of the affected population.

Key Role of Personalized Dosimetry in Dose Adjustment for Selective Internal Radiotherapy: Retrospective Study of Patients Treated With 90Y Resin Microspheres

PURPOSE

Selective internal radiotherapy with 90Y microspheres is widely used for the treatment of patients with liver cancer. A dosimetric analysis using the dosimetry software Simplicit90y (Boston Scientific, Natick, MA) was conducted to define doses to the tumor and healthy liver, and to determine a threshold tumor dose that could predict progression-free survival.

METHODS

Patients experiencing hepatocellular carcinoma and treated with 90Y-labeled resin microspheres were included in a retrospective study. The time-to-progression of the target lesions (TTPLs) and overall survival (OS) were evaluated using Kaplan-Meier tests, and this comparison was based on a log-rank test.

RESULTS

Twenty-four procedures for patients with portal vein thrombosis were realized. Median follow-up was 16 months. A threshold tumor dose of 125 Gy was determined with a sensitivity of 89% and a specificity of 100%. For patients with a tumor dose of less than 125 Gy, the median OS was 7.5 months (95% confidence interval [CI], 5-14 months) and the TTPL was 3 months (95% CI, 2-6 months) versus 33 months (95% CI, 22-39 months) and 23 months (95% CI, 7-38 months), respectively, for those with a tumor dose of 125 Gy or more (P = 0.002 and P = 0.0004).

CONCLUSIONS

Personalized dosimetry based on 99mTc-MAA SPECT/CT is predictive of TTPL and OS in patients with hepatocellular carcinoma. Customized dosimetry software is essential to optimize treatment planning.

Liver metastases

Liver metastases are commonly detected in a range of malignancies including colorectal cancer (CRC), pancreatic cancer, melanoma, lung cancer and breast cancer, although CRC is the most common primary cancer that metastasizes to the liver. Interactions between tumour cells and the tumour microenvironment play an important part in the engraftment, survival and progression of the metastases. Various cells including liver sinusoidal endothelial cells, Kupffer cells, hepatic stellate cells, parenchymal hepatocytes, dendritic cells, resident natural killer cells as well as other immune cells such as monocytes, macrophages and neutrophils are implicated in promoting and sustaining metastases in the liver. Four key phases (microvascular, pre-angiogenic, angiogenic and growth phases) have been identified in the process of liver metastasis. Imaging modalities such as ultrasonography, CT, MRI and PET scans are typically used for the diagnosis of liver metastases. Surgical resection remains the main potentially curative treatment among patients with resectable liver metastases. The role of liver transplantation in the management of liver metastasis remains controversial. Systemic therapies, newer biologic agents (for example, bevacizumab and cetuximab) and immunotherapeutic agents have revolutionized the treatment options for liver metastases. Moving forward, incorporation of genetic tests can provide more accurate information to guide clinical decision-making and predict prognosis among patients with liver metastases.

Radiopharmaceutical therapy in cancer: clinical advances and challenges

Radiopharmaceutical therapy (RPT) is emerging as a safe and effective targeted approach to treating many types of cancer. In RPT, radiation is systemically or locally delivered using pharmaceuticals that either bind preferentially to cancer cells or accumulate by physiological mechanisms. Almost all radionuclides used in RPT emit photons that can be imaged, enabling non-invasive visualization of the biodistribution of the therapeutic agent. Compared with almost all other systemic cancer treatment options, RPT has shown efficacy with minimal toxicity. With the recent FDA approval of several RPT agents, the remarkable potential of this treatment is now being recognized. This Review covers the fundamental properties, clinical development and associated challenges of RPT.

Radiopharmaceutical therapy is emerging as a safe and effective approach for the treatment of cancer, offering several advantages over existing therapeutic strategies. Here, Sgouros and colleagues provide an overview of the fundamental properties of radiopharmaceutical therapy, discuss agents in use and in clinical development and highlight the associated translational challenges.

Tc-99m-MAA lung shunt fraction before Y-90 radioembolization is low among patients with non-hepatocellular carcinoma malignancies

OBJECTIVE

Lung shunt fraction studies using technetium-99 m macro aggregated albumin are routinely performed before yttrium-90 radioembolization regardless of underlying liver malignancy type. This study evaluates the role of lung shunt fraction studies in hepatocellular carcinoma compared to non-hepatocellular carcinoma liver tumors.

METHODS

A single-institution retrospective analysis of all pre-yttrium-90 technetium-99 m macro aggregated albumin lung shunt fraction studies between November 2012 to March 2018 was performed. Patient variables including age, underlying malignancy, laboratory values, lung shunt fraction, and severity of liver disease were compared between hepatocellular carcinoma and non-hepatocellular carcinoma cases.

RESULTS

A total of 734 technetium-99 m macro aggregated albumin studies were identified in 653 patients. Among these cases, the liver tumor was hepatocellular carcinoma in 368 (50.1%), colorectal cancer in 112 (15.3%), neuroendocrine tumor in 89 (12.1%), cholangiocarcinoma in 59 (8.0%), breast cancer in 27 (3.7%), and other metastatic malignancies in 79 (10.7%). The mean lung shunt fraction for non-hepatocellular carcinoma cases was 7.4%, which was significantly lower than the mean lung shunt fraction, 11.7%, for hepatocellular carcinoma cases (P = 0.0001). In only one non-hepatocellular carcinoma case was yttrium-90 radioembolization not pursued due to high lung shunt fraction (69.3%), wherein large scale shunting was grossly apparent on angiography in a patient with metastatic gastrointestinal stromal tumor. In comparison, the lung shunt fraction was too high to pursue radioembolization in 37 hepatocellular carcinoma cases (mean lung shunt fraction 35.1%).

CONCLUSION

Lung shunt fraction appears low among patients with non-hepatocellular carcinoma liver malignancies. Further analysis examining the necessity of pre-Y90 technetium-99 m macro aggregated albumin lung shunt fraction studies in patients with non-hepatocellular carcinoma malignancies is warranted, since a consolidated yttrium-90 radioembolization without prior lung shunt fraction evaluation could reduce resource consumption, improve workflows, and patient access.

History and development of radioembolization: an old idea with modern applications

The current review documents the major hallmarks in the history and development of radioembolization, the origins of which date back to the late 1940s. Radioembolization was initially abandoned because of the increased incidence of adverse effects and lack of commercial interest; however, it regained avid interest in clinical trials and has achieved established clinical utility in the last 15 years. This review focuses on the main stations of the evolution of radioembolization, namely, initial animal and human experimental studies, production of Y-microspheres, development of current therapeutic agents (resin and glass spheres and labeled Lipiodol), prediction and prevention of inadvertent, extrahepatic shunt side effects, initial prospective studies, and large randomized trials till final approval from the relevant official bodies. The historical knowledge of the initial concepts of the method and the limitations encountered may pave the way toward further evolution and possible new applications.

A Novel Approach to Extract Exact Liver Image Boundary from Abdominal CT Scan using Neutrosophic Set and Fast Marching Method

Liver segmentation from abdominal computed tomography (CT) scan images is a complicated and challenging task. Due to the haziness in the liver pixel range, the neighboring organs of the liver have the same intensity level and existence of noise. Segmentation is necessary in the detection, identification, analysis, and measurement of objects in CT scan images. A novel approach is proposed to meet the challenges in extracting liver images from abdominal CT scan images. The proposed approach consists of three phases: (1) preprocessing, (2) CT scan image transformation to neutrosophic set, and (3) postprocessing. In preprocessing, noise in the CT scan is reduced by median filter. A “new structure” is introduced to transform a CT scan image into a neutrosophic domain, which is expressed using three membership subsets: true subset (T), false subset (F), and indeterminacy subset (I). This transform approximately extracts the liver structure. In the postprocessing phase, morphological operation is performed on the indeterminacy subset (I). A novel algorithm is designed to identify the start points within the liver section automatically. The fast marching method is applied at start points that grow outwardly to detect the accurate liver boundary. The evaluation of the proposed segmentation algorithm is concluded using area- and distance-based metrics.

Tc-99m sulfur colloid SPECT-CT and assessment of functional liver reserve after Y90 radioembolization: A case report

INTRODUCTION

Quantitative assessment is an essential tool in determining the proportion of liver to be reserved before lobectomy. Technetium-99 m sulfur colloid single-photon emission computed tomography (Tc-99 m SC SPECT-CT) can help in the quantitative assessment of functioning liver tissues and percentage of liver reserve before segmentectomy and lobectomy Matesan et al. (2017), Bowen et al. (2016) and Lam et al. (2013).

PRESENTATION OF CASE

A 64-year-old man with alcoholic cirrhosis was admitted to our hospital with a 15 × 10 x 13 cm bilobar HCC. Y90 radioembolization was utilized to downstage the liver tumor. On follow-up CT scan of the liver after radiotherapy, the HCC was much reduced to 6.5 cm in size but still viable with elevated alpha fetoprotein ([AFP] from 225 to 381 to 959 ng/mL). Resection was considered. Constitutional indocyanine green retention at 15 min (ICG-R-15) was 22%. We introduced the Tc-99 m SC SPECT-CT scan in order to assess the percentage liver function of each lobe. It showed minimal uptake in the remaining functioning right lobe with a hypertrophic left lobe to whole liver uptake ratio of 87.1%. This finding gave us confidence to perform right hepatectomy.

DISCUSSION

We used Tc-99 m SC SPECT-CT to estimate the normal functional liver reserve after Y90 radioembolization of a hepatocellular carcinoma (HCC). To our understanding, it is the first case report using Tc-99 m SC to predict the percentage of functional liver reserve after yttrium-90 (Y90) radioembolization.

CONCLUSION

Tc-99 m SC SPECT-CT is a novel helper used to assess the differential liver function after Y90 radioembolization of HCC and before segmentectomy and lobectomy of the liver.

Loco-regional intervention for hepatocellular carcinoma

Anatomic location/size and number of lesions, inadequate volume of future liver remnant, or poor coexisting premorbid conditions preclude surgery in the majority of patients with hepatocellular carcinoma (HCC). Liver transplantation can cure some patients with poor liver function, but few patients are eligible because of scarcity of donors. Without specific anti-cancer treatment, the prognosis of HCC is poor. Various locoregional therapies are used to treat patients who are not candidates for surgery, and have emerged as tools for palliation, tumor down-staging, and bridging therapy prior to liver transplantation. Currently, local ablative therapy even competes with partial hepatectomy and liver transplantation as a primary treatment for small HCC. HCC is well suited to treatment with loco-regional therapy because it has a tendency to stay within the liver, with distant metastasis generally occurring late in the course of disease. This suggests that an effective local-regional therapy can have a great impact on HCC patients who are not candidates for surgical treatment. Loco-regional therapy can further be justified because patients with HCC usually die of liver failure consequent to intrahepatic growth resulting in liver tissue destruction, rather than extrahepatic metastases.

90Y-TheraSpheres: The New Look of Yttrium-90

Selective internal radiation therapy with Y-TheraSphere or Y-SIRSphere is used in the treatment of unresectable hepatic malignancies. To the best of our knowledge, this is the first Y-TheraSpheres series. BTG International Canada Inc. provided nonradiated microspheres from the Nordion manufacturer. The histologic processed microspheres were colorless, refractile, polarizable, 20 to 30 μm in diameter, and an occasional internal bulls'-eye seen with the condenser out and an internal cross seen with polarized light. Identical microspheres were identified in 15 hepatectomy specimens from four centers between February 2016 and March 2018. The patients were usually male (male=10, female=5) with a mean age of 59 years. All patients had a prior diagnosis of hepatocellular carcinoma (HCC) and documented Y-TheraSphere (mean duration from last deployment=32 wk). All surgical pathology specimens in these 15 patients were reviewed, but the microspheres were only identified in the hepatectomy specimens. During manuscript preparation, one case of Y-TheraSpheres gastritis was prospectively identified from a separate patient with a history of HCC and Y-TheraSpheres. In conclusion, recognition of Y-TheraSpheres is important so that one may consider the possibility of a nearby malignancy and or establish the cause of the background inflammatory or radiation-related injury. These structures can be easy to miss because the subtle morphology is distinct from previously reported Y-SIRSphere. Clues to the diagnosis include a history of HCC and background radiation change. We report the characteristic morphology as microspheres that overlap in size with Y-SIRSphere, but can be differentiated based on Y-TheraSpheres' colorless appearance with occasional internal bulls'-eyes with the condenser out and an internal cross with polarized light.

Biodistribution, Pharmacokinetics and Efficacy of 188Re(I)-Tricarbonyl-Labeled Human Serum Albumin Microspheres in an Orthotopic Hepatoma Rat Model

BACKGROUND/AIM

The biodistribution, pharmacokinetics and therapeutic evaluation of ¹⁸⁸Re-human serum albumin microspheres (¹⁸⁸Re-HSAM) by labeling with ¹⁸⁸Re(I)-tricarbonyl ion (¹⁸⁸Re(OH₂)₃(CO)₃)+) were investigated in a GP7TB orthotopic hepatoma rat model.

MATERIALS AND METHODS

Male F344 rats received intrahepatic inoculations with GP7TB 1 mm3 cubes. The efficacy of ¹⁸⁸Re-HSAM was examined following a single-dose treatment via the intraarterial route. Rats were monitored for survival until death.

RESULTS

The labeling efficiency of the ¹⁸⁸Re-HSAM was about 80%. After intraarterial administration of ¹⁸⁸Re-HSAM, radioactivity in tumors accumulated from 18.41±3.48 %ID/g at 1 h to 12.43±4.70 %ID/g at 24 h. The tumor/liver ratios ranged from 3.03 at 1 h to 1.89 at 72 h. The major uptake organs of ¹⁸⁸Re-HSAM were liver (73.35%ID to 48.92%ID), tumor (10.54%ID to 3.51%ID) and kidney (7.48 %ID to 0.14%ID). The T_1/2λz of ¹⁸⁸Re-HSAM was 259.34 h after intraarterial injection. The AUC_{(0→96 h)} of ¹⁸⁸Re-HSAM was 0.69 h*% ID/g. In the efficacy study, the median survival time for the rat (n=6), that received normal saline was 80 d. The median survival times for the mice treated with 10 mCi (n=4), 5.2 mCi (n=6) and 2.9 mCi (n=3) of ¹⁸⁸Re-HSAM were 130 d (p=0.003), 106 d (p=0.002) and 83.5 d (p=0.617), respectively. The increase in life span of 10 mCi, 5.2 mCi and 2.9 mCi of ¹⁸⁸Re-HSAM were 62.5%, 32.5% and 4.4%, respectively.

CONCLUSION

Administration of ¹⁸⁸Re-HSAM demonstrated better survival time and therapeutic efficacy at the higher dose in the GP7TB hepatoma model. These results suggested that intraarterial administration of ¹⁸⁸Re-HSAM could provide a benefit and promising strategy for delivery of radiotherapeutics in oncology applications.

Recent advances in transarterial embolotherapies in the treatment of hepatocellular carcinoma

Management of hepatocellular carcinoma (HCC) can be maximized with the utilization of multiple treatment modalities including transplant, surgical resection and locoregional therapies including ablative therapies and transarterial embolotherapies. Although transplant and surgical resection offer the best clinical outcomes, a limited number of patients are amenable to these surgical treatment options due to the advanced disease at presentation. Transarterial embolotherapies including conventional transarterial chemoembolization (cTACE), bland transarterial embolization (TAE), drug-eluting beads transarterial chemoembolization (DEB-TACE) and selective internal radiation therapy (SIRT) with Yttrium 90 (90Y) have played an increasingly important role for these patients with unresectable HCC. With a better understanding of different transarterial embolotherapies, more personalized and precise treatment should be implemented for these patients with unresectable HCC. In this review, the updated evidence on the current role of each embolotherapy in the treatment of HCC is summarized.

Phantom validation of quantitative Y-90 PET/CT-based dosimetry in liver radioembolization

Background

PET/CT has recently been shown to be a viable alternative to traditional post-infusion imaging methods providing good quality images of ⁹⁰Y-laden microspheres after selective internal radiation therapy (SIRT). In the present paper, first we assessed the quantitative accuracy of ⁹⁰Y-PET using an anthropomorphic phantom provided with lungs, liver, spine, and a cylindrical homemade lesion located into the hepatic compartment. Then, we explored the accuracy of different computational approaches on dose calculation, including (I) direct Monte Carlo radiation transport using Raydose, (II) Kernel convolution using Philips Stratos, (III) local deposition algorithm, (IV) Monte Carlo technique (MCNP) considering a uniform activity distribution, and (V) MIRD (Medical Internal Radiation Dose) analytical approach. Finally, calculated absorbed doses were compared with those obtained performing measurements with LiF:Mg,Cu,P TLD chips in a liquid environment.

Results

Our results indicate that despite ⁹⁰Y-PET being likely to provide high-resolution images, the ⁹⁰Y low branch ratio, along with other image-degrading factors, may produce non-uniform activity maps, even in the presence of uniform activity. A systematic underestimation of the recovered activity, both for the tumor insert and for the liver background, was found. This is particularly true if no partial volume correction is applied through recovery coefficients. All dose algorithms performed well, the worst case scenario providing an agreement between absorbed dose evaluations within 20%. Average absorbed doses determined with the local deposition method are in excellent agreement with those obtained using the MIRD and the kernel-convolution dose calculation approach.

Finally, absorbed dose assessed with MC codes are in good agreement with those obtained using TLD in liquid solution, thus confirming the soundness of both calculation approaches. This is especially true for Raydose, which provided an absorbed dose value within 3% of the measured dose, well within the stated uncertainties.

Conclusions

Patient-specific dosimetry is possible even in a scenario with low true coincidences and high random fraction, as in ⁹⁰Y–PET imaging, granted that accurate absolute PET calibration is performed and acquisition times are sufficiently long. Despite Monte Carlo calculations seeming to outperform all dose estimation algorithms, our data provide a strong argument for encouraging the use of the local deposition algorithm for routine ⁹⁰Y dosimetry based on PET/CT imaging, due to its simplicity of implementation.

Combined endeavor of Neutrosophic Set and Chan-Vese model to extract accurate liver image from CT scan

Many different diseases can occur in the liver, including infections such as hepatitis, cirrhosis, cancer and over effect of medication or toxins. The foremost stage for computer-aided diagnosis of liver is the identification of liver region. Liver segmentation algorithms extract liver image from scan images which helps in virtual surgery simulation, speedup the diagnosis, accurate investigation and surgery planning. The existing liver segmentation algorithms try to extort exact liver image from abdominal Computed Tomography (CT) scan images. It is an open problem because of ambiguous boundaries, large variation in intensity distribution, variability of liver geometry from patient to patient and presence of noise. A novel approach is proposed to meet challenges in extracting the exact liver image from abdominal CT scan images. The proposed approach consists of three phases: (1) Pre-processing (2) CT scan image transformation to Neutrosophic Set (NS) and (3) Post-processing. In pre-processing, the noise is removed by median filter. The "new structure" is designed to transform a CT scan image into neutrosophic domain which is expressed using three membership subset: True subset (T), False subset (F) and Indeterminacy subset (I). This transform approximately extracts the liver image structure. In post processing phase, morphological operation is performed on indeterminacy subset (I) and apply Chan-Vese (C-V) model with detection of initial contour within liver without user intervention. This resulted in liver boundary identification with high accuracy. Experiments show that, the proposed method is effective, robust and comparable with existing algorithm for liver segmentation of CT scan images.

Yttrium-90 radioembolization of unresectable hepatocellular carcinoma - a single center experience

PURPOSE

To determine the value of radioembolization (RE) for treatment of unresectable hepatocellular carcinoma (HCC).

PATIENTS AND METHODS

Records of patients undergoing RE for unresectable HCC were retrospectively reviewed. Biochemical and clinical toxicities, imaging response (according to modified Response Evaluation Criteria In Solid Tumors), time-to-progression (TTP) and overall survival (OS) were analyzed. Data were stratified according to clinical and procedural parameters. Univariate and multivariate analyses were performed.

RESULTS

One hundred and fifteen patients (89 male, mean age 69.3 years) underwent 158 REs (119 resin-, 39 glass-based) (Barcelona Clinic Liver Cancer [BCLC]-A: 6.1%, B: 33.9%, C: 60.0%). Median clinical follow-up was 5.9 (0.9-83.5) months. No grade 4 or 5 clinical toxicities were noted. Objective response rate was 35.6%; disease control rate was 76.7%. Median TTP of the treated part of the liver was 4 (0.9-45.4) months. 108/115 patients died during follow-up (median OS 8.4 [0.3-82.8] months after first RE [BCLC-A: 52.8 months, BCLC-B: 12.4 months, BCLC-C: 6.1 months]). On multivariate analysis, baseline Eastern Co-operative Oncology Group status <1, ascites prior to RE and best imaging response were predictors of longer OS. In BCLC-C patients, tumor burden, ascites prior to RE, baseline gamma-glutamyltransferase and Child-Pugh score were predictive of OS.

CONCLUSIONS

RE is safe and effective in carefully selected patients suffering from HCC with a low complication rate. Low baseline Eastern Co-operative Oncology Group status and absence of ascites prior to RE are positive prognostic factors.

Transarterial Radioembolization Versus Concurrent Chemoradiation Therapy for Locally Advanced Hepatocellular Carcinoma: A Propensity Score Matching Analysis

PURPOSE

It is unclear whether the efficacy and safety of concurrent chemoradiation therapy (CCRT) and transarterial radioembolization (TARE) with ⁹⁰Y are comparable in patients with locally advanced hepatocellular carcinoma.

METHODS AND MATERIALS

In total, 209 treatment-naive patients with stage B or C cancer according to the Barcelona Clinic Liver Cancer classification who were treated with TARE or CCRT were analyzed. Propensity scores were calculated and matched at a 1:1 ratio for TARE versus CCRT using age, tumor size, tumor number, portal vein thrombosis, and Barcelona Clinic Liver Cancer staging. In the CCRT group, concurrent hepatic arterial infusion chemotherapy with 5-fluorouracil was delivered at a dosage of 500 mg/d during the first and last 5 days of radiation therapy (median, 45 Gy). Overall survival, freedom from progression, tumor response, and complication rate were compared between the TARE and CCRT groups.

RESULTS

Among 209 patients, 124 (62 undergoing TARE and 62 undergoing CCRT) were selected after propensity score matching. Overall survival (TARE vs CCRT, 14.0 months vs 13.2 months, P=.435) and freedom from progression (6.9 months vs 7.8 months, P=.437) were comparable between the 2 groups. Objective response rates at 1 month after treatment were higher for CCRT than for TARE (46.8% vs 16.1%, P<.001), while objective response rates at 3 months were significantly higher for TARE than for CCRT (39.3% vs 21.4%, P=.04). There was no significant difference in long-term response rates (at 6 months and 1 year) between the 2 groups. The CCRT group experienced a higher rate of curative resection or liver transplantation after treatment than the TARE group, although the statistical significance was marginal (24.2% vs 11.3%, P=.060). Treatment-related complications were less frequent after TARE than after CCRT.

CONCLUSIONS

Both treatments yielded comparable survival rates and long-term response rates in patients with intermediate- or advanced-stage hepatocellular carcinoma. The role of these modalities as a bridge to curative therapy requires further investigation.

Selective internal radiation therapy with SIR-Spheres in hepatocellular carcinoma and cholangiocarcinoma

Hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC) often present at stages where patients have limited treatment options. Use of selective internal radiation therapy (SIRT) with yttrium-90 (Y-90) resin microspheres has progressed as data increasingly speak to its utility in patients with both intermediate and late stage disease in these cancers. In anticipation of the pending completion of several prospective randomized controlled multicenter studies exploring the use of Y-90 resin microspheres in primary liver cancers, this article outlines mechanisms involved in SIRT administration and reviews key efficacy and safety data that are currently available in the literature involving use of this therapy in both HCC and ICC.

Current status and future perspectives on treatment of liver metastasis in colorectal cancer (Review)

Liver metastasis is the most common site of colorectal cancer (CRC) metastasis. Approximately half of all colorectal cancer patients will develop liver metastases. Although radical surgery is the standard treatment modality, only 10-20% of patients are deemed eligible for resection. Despite advances in survival with chemotherapy, surgical resection is still considered the only curative option for patients with liver metastases. Much effort has been expended to address patients with metastatic liver disease. The majority of evidence stated a significant survival benefit with surgical resection to reach an overall 5-year survival rate of 35-55% after hepatic resection. However, still majority of patients will experience disease recurrence even after a successful resection. In this review, we describe current status and controversies related to treatment options for CRC liver metastases and its potential for enhancing oncologic outcomes and improving quality of life.

VESPRO: An Individual Patient Data Prospective Meta-Analysis of Selective Internal Radiation Therapy Versus Sorafenib for Advanced, Locally Advanced, or Recurrent Hepatocellular Carcinoma of the SARAH and SIRveNIB Trials

Background

Untreated advanced hepatocellular carcinoma (HCC) has an overall poor prognosis. Currently there are 2 ongoing prospective randomized controlled trials that are evaluating the efficacy and safety of sorafenib and selective internal radiation therapy (SIRT) with yttrium-90 resin microspheres in patients with advanced HCC. The SorAfenib versus Radioembolisation in Advanced Hepatocellular carcinoma (SARAH; 459 patients) trial is being performed in Europe and the SIRt VErsus SorafeNIB (SIRveNIB; 360 patients) trial in the Asia Pacific region. Prospectively combining the results, these trials will not only allow for increased precision to estimate efficacy (in terms of survival), but will also provide increased statistical power for subgroup analyses.

Objective

To ensure the prospectivity and transparency of the meta-analysis.

Methods

The sirVEnib and SARAH merge PROject (VESPRO) is an individual, patient-data prospective meta-analysis of the SIRveNIB and SARAH randomized trials. The VESPRO protocol includes prespecified hypotheses, inclusion criteria, and outcome measures. The primary outcome measure is overall survival and secondary outcomes include tumor response rate, progression-free survival, progression in the liver as first event, and disease control in the liver. Pooling of toxicity results will allow for robust safety profiles to be established for both therapies, and provides increased statistical power to investigate treatment effects in key subgroups. Analyses will be performed in the intent-to-treat population stratified by trial.

Results

Both studies are expected to demonstrate a survival benefit for SIRT together with a better toxicity profile compared with sorafenib. It is also anticipated that liver progression as the first event would be longer in the intervention compared with the control.

Conclusions

As the results of the 2 trials are not yet known, the methodological strength is enhanced, as biases inherent in conventional meta-analyses are avoided. This has the effect of providing this meta-analysis with the advantages of a single, large,randomized study of 819 patients. It is anticipated that the SARAH and SIRveNIB trial results will be published separately and together with the combined meta-analysis results from VESPRO. The combined dataset will allow the effect of the interventions to be explored with improved reliability/precision with respect to prespecified patient and intervention-level characteristics.

Trial Registration

Australian New Zealand Trials Registry: ACTRN12617000030370.

Enhancing Nanoparticle Accumulation and Retention in Desmoplastic Tumors via Vascular Disruption for Internal Radiation Therapy

Aggressive, desmoplastic tumors are notoriously difficult to treat because of their extensive stroma, high interstitial pressure, and resistant tumor microenvironment. We have developed a combination therapy that can significantly slow the growth of large, stroma-rich tumors by causing massive apoptosis in the tumor center while simultaneously increasing nanoparticle uptake through a treatment-induced increase in the accumulation and retention of nanoparticles in the tumor. The vascular disrupting agent Combretastatin A-4 Phosphate (CA4P) is able to increase the accumulation of radiation-containing nanoparticles for internal radiation therapy, and the retention of these delivered radioisotopes is maintained over several days. We use ultrasound to measure the effect of CA4P in live tumor-bearing mice, and we encapsulate the radio-theranostic isotope ¹⁷⁷Lutetium as a therapeutic agent as well as a means to measure nanoparticle accumulation and retention in the tumor. This combination therapy induces prolonged apoptosis in the tumor, decreasing both the fibroblast and total cell density and allowing further tumor growth inhibition using a cisplatin-containing nanoparticle.

Treating hepatocellular carcinoma with 90Y-bearing microspheres: a review

Hepatocellular carcinoma (HCC) is a disease usually diagnosed in its advanced-stage, and is frequently not amenable to curative surgical treatment. Also, HCC is resistant to chemotherapy and less vulnerable to radiation therapy compared to normal hepatic parenchyma. Both of these facts render the efficacy of adjuvant and palliative treatments problematic. Selective internal radiation therapy (SIRT) with ⁹⁰Y-bearing microspheres is characterized by preferentially delivering substantially high doses of radiation to a liver tumor dose simultaneously limiting the damage to its non-tumorous cells, providing an opportunity for effective local tumor control and even tumor regression therapy. The current article reviews the specific characters, dosimetry, possible applications, and special considerations toward the pre-existing radiation therapy of ⁹⁰Y microsphere SIRT in treating HCC.

Combined sorafenib and yttrium-90 radioembolization for the treatment of advanced hepatocellular carcinoma

BACKGROUND AND AIMS

In this pilot study, we assessed the safety and tolerability of combining sorafenib with ⁹⁰Y radioembolization for the treatment of unresectable hepatocellular carcinoma (hcc).

METHODS

The study, conducted prospectively during 2009-2012, included eligible patients with unresectable hcc and a life expectancy of at least 12 weeks. Each patient received sorafenib (400 mg twice daily) for 6-8 weeks before ⁹⁰Y treatment. Safety and tolerability were assessed.

RESULTS

Of the 40 patients enrolled, 29 completed treatment (combined therapy). In the initial cohort, the most common cause of hcc was hepatitis C (32.5%), and most patients were staged Child A (82.5%). The 29 patients who completed the study had similar baseline characteristics. Grades 1 and 2 toxicities accounted for 77.8% of all adverse events reported. The most common toxicities reported were fatigue (19.0%), alteration in liver function (7.9%), and diarrhea (6.3%). There were 12 grade 3 and 2 grade 4 toxicity events reported. One patient died of liver failure within 30 days after treatment. During the study, the sorafenib dose was reduced in 6 patients (20.7%), and sorafenib had to be interrupted in 4 patients (13.8%) and discontinued in 4 patients (13.8%). The disease control rate was 72.4% per the modified Response Evaluation Criteria in Solid Tumors, and tumour necrosis was observed in 82.8% of patients. Overall survival in patients undergoing combined therapy was 12.4 months.

CONCLUSIONS

Preliminary results demonstrate the safety and tolerability of combining ⁹⁰Y radioembolization and sorafenib for advanced hcc. A larger prospective study is needed to determine the extent of the survival benefit.

Strategic overview on the best treatment option for intrahepaitc hepatocellular carcinoma recurrence

INTRODUCTION

The long-term survival after hepatectomy for HCC remains unsatisfactory because of the high incidence of recurrence. The cumulative 5-year recurrence rate ranged from 60-100% in previous studies and majority of them remains intrahepatic recurrence. The therapeutic modalities commonly used for primary tumors, including surgical resection, liver transplantation, TACE, local ablative therapy and radiotherapy have been used to treat recurrent tumors in the liver remnant and the outcomes with the heterogeneous therapeutic options are reviewed. It is important to note that the level of evidence for most therapeutic options is limited to cohort investigations with few RCTs and most were limited due to enrollment of various tumor stages and did not compare treatment modalities for specific tumor stages.

AREAS COVERED

A literature search for recurrent HCC was performed using Medline and PubMed up to May 2016. Expert commentary: The long term survival results after re-resection for recurrent HCC were favourable and aggressive management of postoperative intrahepatic recurrence remains the most important strategy in prolonging the survival of patients after resection of HCC.

Therapeutic Strategies in HCC: Radiation Modalities

Patients with hepatocellular carcinoma (HCC) comply with an advanced disease and are not eligible for radical therapy. In this distressed scenario new treatment options hold great promise; among them transarterial chemoembolization (TACE) and transarterial metabolic radiotherapy (TAMR) have shown efficacy in terms of both tumor shrinking and survival. External radiation therapy (RTx) by using novel three-dimensional conformal radiotherapy has also been used for HCC patients with encouraging results while its role had been limited in the past for the low tolerance of surrounding healthy liver. The rationale of TAMR derives from the idea of delivering exceptional radiation dose locally to the tumor, with cell killing intent, while preserving normal liver from undue exposition and minimizing systemic irradiation. Since the therapeutic efficacy of TACE is being continuously disputed, the TAMR with ¹³¹I Lipiodol or ⁹⁰Y microspheres has gained consideration providing adequate therapeutic responses regardless of few toxicities. The implementation of novel radioisotopes and technological innovations in the field of RTx constitutes an intriguing field of research with important translational aspects. Moreover, the combination of different therapeutic approaches including chemotherapy offers captivating perspectives. We present the role of the radiation-based therapies in hepatocellular carcinoma patients who are not entitled for radical treatment.

Reduced Periprocedural Analgesia After Replacement of Water for Injection with Glucose 5% Solution as the Infusion Medium for 90Y-Resin Microspheres

The primary aim of our study was to compare the need for periinterventional on-demand analgesia when water for injection (WFI) was replaced with glucose 5% (G5) for ⁹⁰Y-resin microsphere administration.

METHODS

Forty-one patients who received 77 radioembolization procedures with G5 (2014-2015) were retrospectively matched with 41 patients (77 radioembolization procedures) who received radioembolization with WFI (2011-2014) at our center. The need for on-demand pain medication was chosen as an objective and accessible measure of periprocedural pain experienced by patients.

RESULTS

Patients were well matched according to sex, age, tumor type and involvement, and prior antiangiogenic therapies. Periinterventional analgesic requirements were significantly lower for radioembolization procedures performed with G5 than WFI: 5 of 77 (6.5%) versus 29 of 77 (37.7%), P ≤ 0,001, respectively. Early stasis (defined as slowed antegrade flow, before total vascular stasis) occurred in 12 of 154 (7.8%) radioembolization procedures overall and was not different (P ≤ 0.229) between the 2 groups (4/77 [5.2%] vs. 8/77 [10.4%]).

CONCLUSION

Slow pulsatile administration of ⁹⁰Y-resin microspheres with WFI is associated with a low rate of stasis. Replacement of WFI with G5 significantly reduces the need for periprocedural analgesia. These data favor the use G5 for ⁹⁰Y-resin microsphere implantation in daily practice.

Current status of transarterial radioembolization

Unresectable primary and secondary liver malignancies present a major problem in the treatment of solid tumors. Transarterial radioembolization (TARE) is an increasingly used technique for treating various types of malignant liver tumors. This approach is appealing, as the mechanism of action is independent from other loco-regional treatments and potentially complementary to systemic therapies. There are two commercially available products in use for TARE: ⁹⁰Y-resin and ⁹⁰Y-glass microspheres. Currently available data indicates TARE so be safe and effective in hepatocellular carcinoma (HCC) and metastatic liver disease. In HCC the results compare well with chemoembolization, while the role of TARE in combination with kinase inhibitors has yet to be established. Current data on TARE in metastatic liver disease is promising, but there is a strong need for prospective randomized trials comparing TARE and modern chemotherapeutic regimen to support the growing role of TARE in metastatic liver disease.

Transarterial Radioembolization with Yttrium-90 for the Treatment of Hepatocellular Carcinoma

Background

Hepatocellular carcinoma (HCC) is a common cause of worldwide mortality. Transarterial radioembolization (TARE) with yttrium-90 (Y90), a transcatheter intra-arterial procedure performed by interventional radiology, has become widely utilized in managing HCC.

Methods

The following is a focused review of TARE covering its commercially available products, clinical considerations of treatment, salient clinical trial data establishing its utility, and the current and future roles of TARE in the management of HCC.

Results

TARE is indicated for patients with unresectable, intermediate stage HCC. The two available products are glass and resin microspheres. All patients undergoing TARE must be assessed with a history, physical examination, clinical laboratory tests, imaging, and arteriography with macroaggregated albumin. TARE is safe and effective in the treatment of unresectable HCC, as it has a safer toxicity profile than chemoembolization, longer time-to-progression, greater ability to downsize and/or bridge patients to liver transplant, and utility in tumor complicated by portal vein thrombosis. TARE can also serve as an alternative to ablation and chemotherapy.

Conclusion

TARE assumes an integral role in the management of unresectable HCC and has been validated by numerous studies.

90Y Radioembolization of Colorectal Hepatic Metastases Using Glass Microspheres: Safety and Survival Outcomes from a 531-Patient Multicenter Study

Hepatic metastases of colorectal carcinoma are a leading cause of cancer-related mortality. Most colorectal liver metastases become refractory to chemotherapy and biologic agents, at which point the median overall survival declines to 4-5 mo. Radioembolization with (90)Y has been used in the salvage setting with favorable outcomes. This study reports the survival and safety outcomes of 531 patients treated with glass-based (90)Y microspheres at 8 institutions, making it the largest (90)Y study for patients with colorectal liver metastases.

METHODS

Data were retrospectively compiled from 8 institutions for all (90)Y glass microsphere treatments for colorectal liver metastases. Exposure to chemotherapeutic or biologic agents, prior liver therapies, biochemical parameters before and after treatment, radiation dosimetry, and complications were recorded. Uni- and multivariate analyses for predictors of survival were performed. Survival outcomes and clinical or biochemical adverse events were recorded.

RESULTS

In total, 531 patients received (90)Y radioembolization for colorectal liver metastases. The most common clinical adverse events were fatigue (55%), abdominal pain (34%), and nausea (19%). Grade 3 or 4 hyperbilirubinemia occurred in 13% of patients at any time. The median overall survival from the first (90)Y treatment was 10.6 mo (95% confidence interval, 8.8-12.4). Performance status, no more than 25% tumor burden, no extrahepatic metastases, albumin greater than 3 g/dL, and receipt of no more than 2 chemotherapeutic agents independently predicted better survival outcomes.

CONCLUSION

This multiinstitutional review of a large cohort of patients with colorectal liver metastases treated with (90)Y radioembolization using glass microspheres has demonstrated promising survival outcomes with low toxicity and low side effects. The outcomes were reproducible and consistent with prior reports of radioembolization.

Radioembolization with Yttrium-90 microspheres for patients with unresectable hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is aggressive primary malignancy of the liver that most commonly presents late in the disease course. As a result, the majority of patients are not candidates for curative therapies. Locoregional therapies including Yttrium-90 (Y-90) radioembolization play an important role in management of the vast majority of patients with HCC.

METHODS

Patients with unnresectable HCC (n=17) treated with Y-90 radioembolization from 2005 to 2014 were evaluated retrospectively. Data was abstracted from medical records including patient charts, laboratory data, and imaging. Toxicities were recorded using Common Terminology Criteria 3.0. Response was recorded according to modified RECIST (mRECIST) criteria.

RESULTS

Seventeen patients received 33 treatments with Y-90 radioembolization. A majority (65%) received TheraSphere with a minority (35%) receiving SIR-Spheres. The median treatment activity delivered was 1.725 gBq (range, 1.4-2.5 gBq). The median treatment dose delivered was 100 Gy (range, 90-120 Gy). The median lung shunt fraction was 2.02% (range, 1.5-4.1%). The most common clinical toxicity among all patients was nausea and vomiting (59%), primarily grade 1 and 2. Other post-treatment findings included abdominal pain (29%), fatigue (53%), and weight loss (18%). One patient developed a grade 5 gastric ulcer after the treatment. A clinical benefit, defined as patients achieving complete response (CR), partial response (PR) or stable disease (SD), was seen in 48% of patients. PR was seen in 24% of cases; progressive disease (PD) was noted in 35%. Patients survived for a median of 8.4 months (range, 1.3 to 21.1 months) after the first radioembolization treatment. Median survival after Y-90 treatment was 8.4 months among patients treated TheraSphere as compared with 7.8 months in patients treated with SIR-Spheres. The mean overall survival from the time of diagnosis was 11.7 months (range, 3.4 to 43.2 months).

CONCLUSIONS

For patients with unresectable HCC, Y-90 radioembolization is a safe and well-tolerated procedure. Our experience suggests that a significant percentage of patients achieve clinical benefit including many with PR. Survival after treatment from this single-center, transplant center is in line with prior reports. Prospective, randomized data is required to compare radioembolization with other therapies including chemoembolization and systemic therapy with sorafenib.

[Selective internal radiotherapy (SIRT) of liver tumors]

METHODICAL INNOVATIONS

Selective internal radiotherapy (SIRT) is a safe and efficacious, minimally invasive procedure to treat primary and secondary unresectable liver tumors. For hepatocellular carcinoma (HCC), SIRT has proven to be a well-tolerated therapy option even in advanced stages of disease.

STANDARD RADIOLOGICAL METHODS

In cases of portal vein thrombosis SIRT is the alternative to transarterial chemoembolization (TACE).

PERFORMANCE

The role of SIRT regarding downstaging and bridging to transplantation is promising and SIRT has also been shown to be highly effective and well-tolerated in metastastic liver disease.

ACHIEVEMENTS

The results of prospective randomized trials are awaited to prove the efficiency and safety of SIRT described in numerous retrospective and prospective non-randomized studies.

PRACTICAL RECOMMENDATIONS

The indications are established within the framework of a tumor board.

A computational tool for patient specific dosimetry and radiobiological modeling of selective internal radiation therapy with (90)Y microspheres

In recent years we have witnessed tremendous progress in selective internal radiation therapy. In clinical practice, quite often, radionuclide therapy is planned using simple models based on standard activity values or activity administered per unit body weight or surface area in spite of the admission that radiation-dose methods provide more accurate dosimetric results. To address that issue, the authors developed a Matlab-based computational software, named Patient Specific Yttrium-90 Dosimetry Toolkit (PSYDT). PSYDT was designed for patient specific voxel-based dosimetric calculations and radiobiological modeling of selective internal radiation therapy with (90)Y microspheres. The developed toolkit is composed of three dimensional dose calculations for both bremsstrahlung and beta emissions. Subsequently, radiobiological modeling is performed on a per-voxel basis and cumulative dose volume histograms (DVHs) are generated. In this report we describe the functionality and visualization features of PSYDT.

Safety of Radioembolization with (90)Yttrium Resin Microspheres Depending on Coiling or No-Coiling of Aberrant/High-Risk Vessels

PURPOSE

To evaluate the safety of radioembolization (RE) with (90)Yttrium ((90)Y) resin microspheres depending on coiling or no-coiling of aberrant/high-risk vessels.

MATERIALS AND METHODS

Early and late toxicity after 566 RE procedures were analyzed retrospectively in accordance with the National Cancer Institute's Common Terminology Criteria for Adverse Events (CTCAE v3.0). For optimal safety, aberrant vessels were either coil embolized (n = 240/566, coiling group) or a more peripheral position of the catheter tip was chosen to treat right or left liver lobes (n = 326/566, no-coiling group).

RESULTS

Clinically relevant late toxicities (≥ Grade 3) were observed in 1% of our overall cohort. The no-coiling group had significantly less "any" (P = 0.0001) or "clinically relevant" (P = 0.0003) early toxicity. There was no significant difference (P > 0.05) in delayed toxicity in the coiling versus the no-coiling group. No RE-induced liver disease was noted after all 566 procedures.

CONCLUSION

RE with (90)Y resin microspheres is a safe and effective treatment option. Performing RE without coil embolization of aberrant vessels prior to treatment could be an alternative for experienced centers.