General selection criteria of patients for radioembolization of liver tumors: an international working group report. Am J Clin Oncol. 2011;34:337-341. [PMID: 20921882 DOI: 10.1097/coc.0b013e3181ec61bb]

Chemoembolization, Radioembolization, and Percutaneous Ablation: New Opportunities for Treating Ovarian Cancer Liver Metastasis

OPINION STATEMENT

Parenchymal liver metastases from ovarian cancer, occurring in 2-12.5% of cases, significantly worsen prognosis. While surgery and systemic treatments remain primary options, unresectable or chemotherapy-resistant multiple liver metastases pose a significant challenge. Recent advances in liver-directed therapies, including radiofrequency ablation, microwave ablation, cryoablation, transarterial chemoembolization (TACE), and radioembolization, offer potential treatment alternatives. However, the efficacy of these techniques is limited by factors such as tumor size, number, and location. The ideal candidate for tumor ablation is a patient with paucifocal disease, a single tumor up to 5 cm or up to 3 tumors smaller than 3 cm and tumors 1 cm away from major bile ducts and high-flow vessels. Transarterial chemoembolization could be performed in patients with less than 70% tumor load. Differently, radioembolization is available with less limitation on the sites or number of liver cancers. Radioembolization techniques are also able to downsize liver metastases. However, there are limited data regarding the outcomes of loco-regional therapy in patients with hepatic metastases from ovarian cancer. Advancing liver-directed therapies through interventional oncology, combined with robust data on the oncological efficacy of these local treatments, will validate their potential as effective locoregional therapies for liver metastases. This could offer a promising treatment option for patients with ovarian cancer and unresectable hepatic metastases.

The Future of Interventions for Stage IV Colorectal Cancers

Future options for the management of stage IV colorectal cancer are primarily focused on personalized and directed therapies. Interventions include precision cancer medicine, utilizing nanocarrier platforms for directed chemotherapy, palliative pressurized intraperitoneal aerosol chemotherapy (PIPAC), adjunctive oncolytic virotherapy, and radioembolization techniques. Comprehensive genetic profiling provides specific tumor-directed therapy based on individual genetics. Biomimetic magnetic nanoparticles as chemotherapy delivery systems may reduce systemic side effects of traditional chemotherapy by targeting tumor cells and sparing healthy cells. PIPAC is a newly emerging option for patients with peritoneal metastasis from colorectal cancer and is now being used internationally, showing promising results as a palliative therapy for colorectal cancer. Oncolytic virotherapy is another emerging potential treatment option, especially when combined with standard chemotherapy and/or radiation, as well as immunotherapy. And finally, radioembolization with yttrium-90 ( 90 Y) microspheres has shown some success in treating patients with unresectable liver metastasis from colorectal cancer via selective arterial injection.

AAPM Medical Physics Practice Guideline 14.a: Yttrium-90 microsphere radioembolization

Radioembolization using Yttrium-90 (90 Y) microspheres is widely used to treat primary and metastatic liver tumors. The present work provides minimum practice guidelines for establishing and supporting such a program. Medical physicists play a key role in patient and staff safety during these procedures. Products currently available are identified and their properties and suppliers summarized. Appropriateness for use is the domain of the treating physician. Patient work up starts with pre-treatment imaging. First, a mapping study using Technetium-99m (Tc-99m ) is carried out to quantify the lung shunt fraction (LSF) and to characterize the vascular supply of the liver. An MRI, CT, or a PET-CT scan is used to obtain information on the tumor burden. The tumor volume, LSF, tumor histology, and other pertinent patient characteristics are used to decide the type and quantity of 90 Y to be ordered. On the day of treatment, the appropriate dose is assayed using a dose calibrator with a calibration traceable to a national standard. In the treatment suite, the care team led by an interventional radiologist delivers the dose using real-time image guidance. The treatment suite is posted as a radioactive area during the procedure and staff wear radiation dosimeters. The treatment room, patient, and staff are surveyed post-procedure. The dose delivered to the patient is determined from the ratio of pre-treatment and residual waste exposure rate measurements. Establishing such a treatment modality is a major undertaking requiring an institutional radioactive materials license amendment complying with appropriate federal and state radiation regulations and appropriate staff training commensurate with their respective role and function in the planning and delivery of the procedure. Training, documentation, and areas for potential failure modes are identified and guidance is provided to ameliorate them.

Yttrium-90 transarterial radioembolization and capecitabine in hepatocellular carcinoma with portal vein involvement

Hepatocellular carcinoma (HCC) with portal vein tumor thrombus is considered an advanced stage disease. Non-surgical local and systemic therapies are the only treatment options available. To analyze the survival and toxicity outcomes of systemic treatment concurrent with yttrium-90 transarterial radioembolization in HCC with liver-limited disease and portal vein involvement with Child-Pugh B liver reserve. The medical records of 22 patients who underwent yttrium-90 transarterial radioembolization concomitant with capecitabine chemotherapy as first-line treatment between 2014 and 2019 were retrospectively reviewed. Twenty-two patients were included in the study. Grade 3 to 4 side effects were evaluated, and hepatic encephalopathy developed in 1 patient after yttrium-90 transarterial radioembolization. In the fourth month of radiological evaluation, 11 patients had a partial response (50%), 5 patients had stable disease (22.7%), and 6 patients (27.3%) developed progressive disease. The median survival time was 21 months. Combined treatment with yttrium-90 transarterial radioembolization and capecitabine may be an effective and safe treatment option. Treatment was associated with a median overall survival of 21 months and a disease control rate of 72.7% at 4 months in patients with inoperable HCC.

Maximum tumor-absorbed dose measured by voxel-based multicompartmental dosimetry as a response predictor in yttrium-90 radiation segmentectomy for hepatocellular carcinoma

OBJECTIVE

Advances in hepatic radioembolization are based on a selective approach with radical intent and the use of multicompartment dosimetric analysis. The objective of this study is to assess the utility of voxel-based dosimetry in the quantification of actual absorbed doses in radiation segmentectomy procedures and to establish cutoff values predictive of response.

METHODS

Ambispective study in hepatocarcinoma patients treated with radiation segmentectomy. Calculated dosimetric parameters were mean tumor-absorbed dose, maximum tumor AD, minimal tumor AD in 30, 50, and 70% of tumor volume and mean AD in non-tumor liver. The actual absorbed dose (aAD) was calculated on the Y-90-PET/CT image using 3D voxel-based dosimetry software. To assess radiological response, localized mRECIST criteria were used. The objective response rate (ORR) was defined as CR or PR.

RESULTS

Twenty-four HCC patients, BCLC 0 (5), A (17) and B (2) were included. The mean yttrium-90 administered activity was 1.38 GBq in a mean angiosome volume of 206.9 cc and tumor volume 56.01 cc. The mean theoretical AD was 306.3 Gy and aAD 352 Gy. A very low concordance was observed between both parameters (rho_c 0.027). ORR at 3 and 6 m was 84.21% and 92.31%, respectively. Statistically significant relationship was observed between the maximum tumor-absorbed dose and complete radiological response at 3 m (p 0.022).

CONCLUSION

A segmental approach with radical intention leads to response rates greater than 90%, being the tumor maximum absorbed dose the dosimetric parameter that best predicts radiological response in voxel-based dosimetry.

Italian Clinical Practice Guidelines on Cholangiocarcinoma - Part II: Treatment

Currently, the only curative treatment for cholangiocarcinoma (CCA) is surgical resection, though this treatment is possible in less than 40% of patients. However, recent improvements in preoperative management have led to a higher number of patients who are candidates for this procedure. For unresectable patients, progress is ongoing in terms of locoregional and chemoradiation treatments and target therapies, especially in the definition of patient selection criteria. This is the second part of the Italian CCA guidelines, dealing with CCA treatment, that have been formulated in accordance with Italian National Institute of Health indications and developed according to the GRADE method and related advancements.

Lung Metastasis Postradioembolization of Hepatocellular Carcinoma With Tumor in Vein

Transarterial radioembolization (TARE) is one of the few treatment options available for infiltrative hepatocellular carcinoma with tumor in vein. This is backed by the published data showing marginally favorable toxicity profile compared with other locoregional and systemic therapies. Although lung shunt fraction studies are performed to prevent radiation injury to the lungs, TARE-induced embolization/metastasis to the lungs has not been reported before. We report an intriguing case of new lung metastases within 1 month after TARE for infiltrative hepatocellular carcinoma with a tumor in the vein, with only a slightly elevated but acceptable lung shunt fraction. This report brings to light the possibility of such a complication and argues for improved preprocedural assessment of a tumor in vein burden and embolization potential.

Radioembolization for the Treatment of Primary and Metastatic Liver Cancers

Radioembolization using ⁹⁰Y microspheres (glass or resin) has been introduced as an effective intraarterial therapy for unresectable primary and metastatic liver cancers. Although the basic therapeutic effect of chemoembolization results from ischemia, the therapeutic efficacy of radioembolization comes from radiation. Furthermore, compared with surgical resection and local ablation therapy, radioembolization is available with less limitation on the sites or number of liver cancers. The radioisotope ⁹⁰Y is a β-radiation emitter without γ-radiation, with the emission of secondary bremsstrahlung photons and small numbers of positrons. Administration of ⁹⁰Y microspheres into the hepatic artery can deliver a high dose of radiation selectively to the target tumor with limited radiation exposure to the surrounding normal parenchyma, and has low systemic toxicity. In general, radioembolization has been considered for patients with unresectable primary or metastatic liver-only or liver-dominant cancers with no ascites or other clinical signs of liver failure, life expectancy of > 12 weeks, and good performance status. Here, we review the current radioactive compounds, pretreatment assessment, and indications for radioembolization in patients with hepatocellular carcinoma, intrahepatic cholangiocarcinoma, and liver metastases from colorectal cancer.

Progress in research of hepatocellular carcinoma with tumor thrombus

Hepatocellular carcinoma (HCC) with tumor thrombus is a hot and difficult issue in the study of HCC, and many key issues concerning this condition are still controversial. Clinical guidelines and treatment recommendations vary widely between the East and the West, and efficacy remains unsatisfactory. In recent years, with the progress of comprehensive tumor treatment concept and the rapid development of surgical techniques, perioperative management, interventional therapy, radiotherapy, targeted therapy, and other treatment methods, the overall survival rate of HCC with tumor thrombus has been significantly extended and encouraging efficacy has been achieved. However, the core issues on how to select individualized treatment to achieve optimal treatment and how to prevent postoperative recurrence still need to be studied and discussed. This article reviews the progress in the research of hepatic carcinoma with portal vein thrombus, inferior vena cava thrombus, or bile duct thrombus.

Preparation and characterization of inorganic radioactive holmium-166 microspheres for internal radionuclide therapy

Microspheres with high specific activities of radionuclides are very interesting for internal radiotherapy treatments. This work focuses on the formulation and characterization of inorganic microspheres with a high content of holmium and therefore a high specific radioactivity of holmium-166. Two novel formulations of inorganic microspheres were obtained by dispersing solid holmium acetylacetonate microspheres (Ho₂(AcAc)₃-ms) in NaH₂PO₄ or NaOH solutions followed by 2 h incubation at room temperature. By exchange of acetylacetonate with phosphate or hydroxyl ions, holmium phosphate microspheres (HoPO₄-ms) and holmium hydroxide microspheres (Ho(OH)₃-ms) were formed respectively. The inorganic microspheres had a significantly smaller diameter (28.5 ± 4.4 μm (HoPO₄-ms) and 25.1 ± 3.5 μm (Ho(OH)₃-ms)) than those of Ho₂(AcAc)₃-ms (32.6 ± 5.2 μm). The weight percentage of holmium-165 in the microspheres increased significantly from 47% (Ho₂(AcAc)₃-ms) to 55% (HoPO₄-ms) and 73% (Ho(OH)₃-ms). After preparation of both HoPO₄-ms and Ho(OH)₃-ms, the stable holmium-165 isotope was partly converted by neutron activation into radioactive holmium-166 to yield radioactive microspheres. High specific activities were achieved ranging from 21.7 to 59.9 MBq/mg (¹⁶⁶HoPO₄-ms) and from 28.8 to 79.9 MBq/mg (¹⁶⁶Ho(OH)₃-ms) depending on the neutron activation time. The structure of both microspheres was preserved up to neutron activations of 6 h in a thermal neutron flux of 4.72 × 10¹⁶ n m^-2 s^-1. After activation, both microspheres revealed excellent stability in administration fluids (saline and phosphate buffer) having less than 0.05% of holmium released after 72 h incubation. Finally, the hemocompatibility of these inorganic microspheres was evaluated and it was shown that the microspheres did cause neither hemolysis nor depletion or inhibition of the coagulation factors of the intrinsic blood coagulation pathway meaning that the microspheres have a good hemocompatibility. Overall, this work shows that radioactive inorganic microspheres with high specific activities of holmium-166 can be prepared which potentially can be used for internal radionuclide therapy.

Patterns of Care and Outcomes of Definitive External Beam Radiotherapy and Radioembolization for Localized Hepatocellular Carcinoma: A Propensity Score-adjusted Analysis

OBJECTIVES

Most localized hepatocellular carcinoma (HCC) patients are not surgically operable or transplantation candidates, increasing the role for nonsurgical therapies. Ablative external beam radiotherapy (XRT) and transarterial radioembolization (TARE) are emerging radiotherapeutic treatments for localized HCC. We sought to evaluate their utilization and efficacy in a large nationwide cohort.

MATERIALS AND METHODS

We conducted an observational study of 2685 patients from the National Cancer Database (NCDB) diagnosed with American Joint Committee on Cancer 7th edition clinical stage I to III HCC between 2004 and 2015, treated with definitive-intent XRT delivered in 1 to 15 fractions or TARE. The association between treatment modality (XRT vs. TARE) and overall survival (OS) was defined using propensity score-weighted Kaplan-Meier estimators and propensity score-weighted multivariable Cox regressions.

RESULTS

Among 2685 patients, 2007 (74.7%) received TARE and 678 (25.3%) received XRT, with increasing usage for both from 2004 to 2015 (Ptrend<0.001), but with overall greater uptake and absolute usage of TARE. Patients who received TARE were more likely to have elevated alpha fetoprotein and more advanced stage (P<0.05 for all). Median OS was 14.5 months for the entire cohort. XRT was associated with an OS advantage compared with TARE on propensity score-unadjusted analysis (adjusted hazard ratio [AHR], 0.89; 95% confidence interval, 0.79-1.00; P=0.049), but not on propensity score-adjusted analysis (AHR, 0.99; 95% confidence interval, 0.86-1.13; P=0.829).

CONCLUSIONS

Our study demonstrates that while both XRT and TARE usage have increased with time, there was greater uptake and absolute use of TARE. We found no difference in survival between XRT and TARE after propensity score adjustment.

Red Flags, Pitfalls, and Cautions in Y90 Radiotherapy

Radioembolization with yttrium-90 (Y90) microspheres is increasingly used to palliate patients with liver-dominant malignancy. With appropriate patient selection, this outpatient treatment is efficacious with limited toxicity profile. This article reviews common scenarios that can present in daily practice including evaluation of liver functions, evaluation of previous therapies, integrating Y90 into ongoing systemic therapy, determining performance status, and considering retreatment for patients who have already undergone Y90 who have hepatic dominant progression. Finally, we address the importance of evaluating tumors in potential watershed zones to maximize treatment response by using c-arm computed tomography. Many of these potential variables can overlap in an individual patient. By considering these factors individually, the consulting Interventional Radiologist can present a thorough treatment plan with a full description of expected outcomes and toxicities to clinic patients.

History and Evolution of Yttrium-90 Radioembolization for Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the most common form of primary liver cancer and affects millions worldwide. Due to the lack of effective systemic therapies for HCC, researchers have been investigating the use of locoregional tumor control with Yttrium-90 (Y90) radioembolization since the 1960s. Following the development of glass and resin Y90 microspheres in the early 1990s, Y90 radioembolization has been shown to be a safe and efficacious treatment for patients with HCC across Barcelona Clinic Liver Cancer (BCLC) stages. By demonstrating durable local control, good long term outcomes, and equivalent if not superior tumor responses and tolerability when compared to alternative therapies including transarterial chemoembolization (TACE) and sorafenib, Y90 radioembolization is being increasingly used in HCC treatment. More recently, investigations into variations in Y90 radioembolization technique including radiation segmentectomy and radiation lobectomy have further expanded its clinical utility. Here, we discuss the history and evolution of Y90 use in HCC. We outline key clinical trials that have established the safety and efficacy of Y90 radioembolization, and also summarize trials comparing its efficacy to existing HCC treatments. We conclude by reviewing the techniques of radiation segmentectomy and lobectomy, and by discussing dosimetry.

Response and Overall Survival for Yttrium-90 Radioembolization of Hepatic Sarcoma: A Multicenter Retrospective Study

PURPOSE

To evaluate the effectiveness and safety of yttrium-90 transarterial radioembolization (TARE) for the treatment of primary and metastatic soft tissue sarcoma (STS) of the liver.

MATERIALS AND METHODS

A retrospective review of 39 patients with primary (n = 2) and metastatic (n = 37) hepatic STS treated with TARE at 4 institutions was performed. Fourteen STS subtypes were included, with leiomyosarcoma being the most common (51%). TARE with glass (22 patients) or resin (17 patients) microspheres was performed, with single lobe (17 patients) or bilobar treatment (22 patients) based on disease burden. Adverse events of treatment, overall survival (OS), and tumor response at 3, 6, and 12 months after TARE were assessed per the Response Evaluation Criteria in Solid Tumors.

RESULTS

Fourteen patients demonstrated either partial or complete response to therapy, with an objective response rate of 36%. Thirty patients (77%) demonstrated disease control (DC)-either stable disease or response to treatment. Median OS was 30 months (95% confidence interval 12-43 months) for all patients. DC at 3 months was associated with an increased median OS (44 months) compared with progressive disease (PD) (7.5 months; P < .0001). Patients with DC at 6 months also demonstrated an increased median OS (38 months) compared to patients with PD (17 months; P = .0443). Substantial adverse events included 1 liver abscess, 1 gastric ulceration, and 1 pneumonitis.

CONCLUSIONS

Patients with hepatic STS treated with TARE demonstrated a high rate of DC and a median OS of 30 months, which suggests a role for TARE in the palliation of hepatic STS.

Single-institution experience with selective internal radiation therapy (SIRT) for the treatment of unresectable colorectal liver metastases

BACKGROUND

Liver metastases are the commonest cause of death for patients with colorectal cancer. Growing evidence supports the use of selective internal radiation therapy (SIRT) in combination with conventional chemotherapy regimens for liver-only or liver-dominant unresectable metastatic colorectal cancer.

AIMS

To measure and evaluate outcomes of the first 20 consecutive patients with unresectable colorectal liver metastasis selected for SIRT in addition to their chemotherapy at a single Irish institution.

METHODS

Retrospective case series was performed. Patient charts and medical records were reviewed.

RESULTS

All 20 patients (100%) selected for angiographic workup were subsequently successfully treated with radioembolization. All patients were discharged 1 day post-SIRT. At initial imaging evaluation, 12 (60%) had a partial response in their liver, 2 (10%) had stable disease, and 6 (30%) had liver-specific progressive disease. Median follow up was 10 months (range 6-26). At last follow up, 14 (70%) patients were alive and 6 (30%) deceased. Most recent imaging demonstrated 2 (10%) with a complete response, 7 (35%) had a partial response, 2 (10%) had stable disease, and 9 (45%) had progressive disease within their liver. One patient was downstaged to hepatic resection, and one with a complete hepatic response had his primary sigmoid tumor resected 11 months post-SIRT.

CONCLUSIONS

SIRT is a safe and effective therapy for certain patients with unresectable colorectal liver metastases. This case series supports our opinion that selected patients should be offered SIRT in concert with their medical oncologist, concomitant with their chemotherapy. Larger multi-center studies are required to more clearly define the patient groups that will derive most benefit from SIRT.

Imaging Evaluation Following 90Y Radioembolization of Liver Tumors: What Radiologists Should Know

Radioembolization using beta-emitting yttrium-90 microspheres is being increasingly used for the treatment of primary and metastatic liver cancers. It is a form of intra-arterial brachytherapy which delivers intense radiation to liver tumors with little embolic effect; this mode of action results in unique post-treatment imaging findings. It is important to understand these imaging findings to avoid misinterpretation of tumor response and to determine further management of the disease. Herein, we discuss the current concepts for assessing tumor response, common post-treatment imaging features, and associated complications following radioembolization.

Recommendations for SIR-Spheres Y-90 resin microspheres in chemotherapy-refractory/intolerant colorectal liver metastases

A Spanish expert panel reviewed current evidence for the use of SIR-Spheres Y-90 resin microspheres in patients with chemotherapy refractory/intolerant unresectable colorectal liver metastases. Substantial evidence for its efficacy and safety is available from a randomized controlled study, retrospective comparative studies and several single arm studies. Clinical evidence data obtained from more than 1500 patients have led to the inclusion of selective internal radiation therapy in the 2016 ESMO Clinical Guidelines as third-line treatment. This publication results from an expert panel meeting, where published evidence and author's experiences were shared to position SIR-Spheres Y-90 resin microspheres in Spain for the treatment of chemotherapy refractory/intolerant unresectable colorectal liver metastases, and second, to define the patient subgroup that will benefit the most with this treatment.

Yttrium-90 microsphere radioembolization in unresectable intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinoma is increasing in frequency worldwide, but radical surgical treatment is practicable in 30–40% of cases. The median survival without therapy is about 8 months, increased to 12 months in combination with systemic chemotherapy. Therefore, locoregional therapies, such as, radiofrequency ablation or transarterial chemoembolization have been employed. Radioembolization with yttrium-90 microspheres (90Y-TARE) is a novel intrarterial treatment which could be included in the armamentarium of treatment options, having shown higher median survival (up to 22 months) and low complication rates. Evidence-based algorithms for staging and allocation to treatment should be defined in the future, after robust results obtained through randomized controlled trials, thus establishing the exact role and timing of 90Y-TARE in the treatment protocol of unresectable intrahepatic cholangiocarcinoma.

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.

Efficacy of radioembolization according to tumor morphology and portal vein thrombosis in intermediate-advanced hepatocellular carcinoma

PURPOSE

We analyzed overall survival (OS) following radioembolization according to macroscopic growth pattern (nodular vs infiltrative) and vascular invasion in intermediate-advanced hepatocellular carcinoma (HCC).

METHODS

Between September 2005 and November 2013, 104 patients (50.0% portal vein thrombosis [PVT], 29.8% infiltrative morphology) were treated.

RESULTS

Median OS differed significantly between patients with segmental and lobar or main PVT (p = 0.031), but was 17 months in both those with patent vessels and segmental PVT. Median OS did not differ for infiltrative and nodular HCC. Median OS was prolonged in patients with a treatment response at 3 months (p = 0.023). Prior TACE was also a significant predictor of improved OS.

CONCLUSION

A further indication for radioembolization might be infiltrative HCC, since OS was similar to nodular types.

Radioembolization with Yttrium-90 microspheres in hepatocellular carcinoma: Role and perspectives

Transarterial radioembolization (TARE) is a form of brachytherapy in which intra-arterially injected yttrium-90-loaded microspheres serve as a source for internal radiation purposes. On the average, it produces disease control rates exceeding 80% and it is a consolidated therapy for hepatocellular carcinoma (HCC); however, current data are all based on retrospective series or non-controlled prospective studies since randomized controlled trials comparing it with the other liver-directed therapies for intermediate and locally advanced stage HCC are still underway. The data available show that TARE provides similar or even better survival rates when compared to transarterial chemoembolization (TACE). First-line TARE is best indicated for both intermediate-stage patients (staged according to the barcelona clinic liver cancer staging classification) who have lesions which respond poorly to TACE due to multiple tumors or a large tumor burden, and for locally advanced-stage patients with solitary tumors, and segmental or lobar portal vein tumor thrombosis. In addition, emerging data have suggested the use of TARE in patients who are classified slightly beyond the Milan criteria regarding radical treatment for downstaging purposes. As a second-line treatment, TARE can also be applied in patients progressing to TACE or sorafenib; a large number of phase II/III trials are ongoing with the purpose of evaluating the best association with systemic therapies. Transarterial radioembolization is very well tolerated and has a low rate of complications which are mainly related to unintended non-target tissue irradiation, including the surrounding liver parenchyma. The complications can be additionally reduced by accurate patient selection and a strict pre-treatment evaluation including dosimetry and assessment of the vascular anatomy. Since a correct treatment algorithm for potential TARE candidates is not clear and standardized, this comprehensive review analyzes the best selection criteria for patients who really benefit from TARE and also the new advances of this therapy, which can be a very important weapon against HCC.

Fusion dual-tracer SPECT-based hepatic dosimetry predicts outcome after radioembolization for a wide range of tumour cell types

Purpose

Fusion dual-tracer SPECT imaging enables physiological rather than morphological voxel-based partitioning and dosimetry for ⁹⁰Y hepatic radioembolization (RE). We evaluated its prognostic value in a large heterogeneous cohort of patients with extensive hepatic malignancy.

Methods

A total of 122 patients with primary or secondary liver malignancy (18 different cell types) underwent SPECT imaging after intraarterial injection of ^99mTc macroaggregated albumin (TcMAA) as a simulation of subsequent ⁹⁰Y microsphere distribution, followed by administration of an excess of intravenous ^99mTc-labelled sulphur colloid (TcSC) as a biomarker for functional liver, and a second SPECT scan. TcMAA distribution was used to estimate ⁹⁰Y radiation absorbed dose in tumour (D_T) and in functional liver. Laboratory and clinical follow-up were recorded for 12 weeks after RE, and radiographic responses according to (m)RECIST were evaluated at 3 and 6 months. Dose–response relationships were determined for efficacy and toxicity.

Results

Patients were treated with a median of 1.73 GBq activity of resin microspheres (98 patients) or glass microspheres (24 patients), in a whole-liver approach (97 patients) or a lobar approach (25 patients). The objective response rate was 41 % at 3 months and 48 % at 6 months. Response was correlated with D_T (P < 0.01). Median overall survival was 10.1 months (95 % confidence interval 7.4 – 12.8 months). Responders lived for 36.0 months compared to 8.7 months for nonresponders (P < 0.01). Stratified for tumour cell type, D_T was independently associated with survival (P < 0.01). Absorbed dose in functional liver was correlated with toxicity grade change (P < 0.05) and RE-induced liver disease (P < 0.05).

Conclusion

Fusion dual-tracer SPECT imaging offers a physiology-based functional imaging tool to predict efficacy and toxicity of RE. This technique can be refined to define dosing thresholds for specific tumour types and treatments, but appears generally predictive even in a heterogeneous cohort.

Electronic supplementary material

The online version of this article (doi:10.1007/s00259-015-3048-z) contains supplementary material, which is available to authorized users.

Radioembolization with Yttrium-90 microspheres in hepatocellular carcinoma: Role and perspectives

Transarterial radioembolization (TARE) is a form of brachytherapy in which intra-arterially injected yttrium-90-loaded microspheres serve as a source for internal radiation purposes. On the average, it produces disease control rates exceeding 80% and it is a consolidated therapy for hepatocellular carcinoma (HCC); however, current data are all based on retrospective series or non-controlled prospective studies since randomized controlled trials comparing it with the other liver-directed therapies for intermediate and locally advanced stage HCC are still underway. The data available show that TARE provides similar or even better survival rates when compared to transarterial chemoembolization (TACE). First-line TARE is best indicated for both intermediate-stage patients (staged according to the barcelona clinic liver cancer staging classification) who have lesions which respond poorly to TACE due to multiple tumors or a large tumor burden, and for locally advanced-stage patients with solitary tumors, and segmental or lobar portal vein tumor thrombosis. In addition, emerging data have suggested the use of TARE in patients who are classified slightly beyond the Milan criteria regarding radical treatment for downstaging purposes. As a second-line treatment, TARE can also be applied in patients progressing to TACE or sorafenib; a large number of phase II/III trials are ongoing with the purpose of evaluating the best association with systemic therapies. Transarterial radioembolization is very well tolerated and has a low rate of complications which are mainly related to unintended non-target tissue irradiation, including the surrounding liver parenchyma. The complications can be additionally reduced by accurate patient selection and a strict pre-treatment evaluation including dosimetry and assessment of the vascular anatomy. Since a correct treatment algorithm for potential TARE candidates is not clear and standardized, this comprehensive review analyzes the best selection criteria for patients who really benefit from TARE and also the new advances of this therapy, which can be a very important weapon against HCC.

Radioembolization with Yttrium-90 microspheres in hepatocellular carcinoma: Role and perspectives

Transarterial radioembolization (TARE) is a form of brachytherapy in which intra-arterially injected yttrium-90-loaded microspheres serve as a source for internal radiation purposes. On the average, it produces disease control rates exceeding 80% and it is a consolidated therapy for hepatocellular carcinoma (HCC); however, current data are all based on retrospective series or non-controlled prospective studies since randomized controlled trials comparing it with the other liver-directed therapies for intermediate and locally advanced stage HCC are still underway. The data available show that TARE provides similar or even better survival rates when compared to transarterial chemoembolization (TACE). First-line TARE is best indicated for both intermediate-stage patients (staged according to the barcelona clinic liver cancer staging classification) who have lesions which respond poorly to TACE due to multiple tumors or a large tumor burden, and for locally advanced-stage patients with solitary tumors, and segmental or lobar portal vein tumor thrombosis. In addition, emerging data have suggested the use of TARE in patients who are classified slightly beyond the Milan criteria regarding radical treatment for downstaging purposes. As a second-line treatment, TARE can also be applied in patients progressing to TACE or sorafenib; a large number of phase II/III trials are ongoing with the purpose of evaluating the best association with systemic therapies. Transarterial radioembolization is very well tolerated and has a low rate of complications which are mainly related to unintended non-target tissue irradiation, including the surrounding liver parenchyma. The complications can be additionally reduced by accurate patient selection and a strict pre-treatment evaluation including dosimetry and assessment of the vascular anatomy. Since a correct treatment algorithm for potential TARE candidates is not clear and standardized, this comprehensive review analyzes the best selection criteria for patients who really benefit from TARE and also the new advances of this therapy, which can be a very important weapon against HCC.

Radioembolization for hepatocellular carcinoma: current role and future directions – the medical oncologist's perspective

SUMMARY 

The incidence and impact of hepatocelluar carcinoma (HCC) continues to increase worldwide. While radical therapies such as resection, radiofrequency ablation or transplantation are potentially curative for patients with early-stage HCC, the majority of patients in routine practice present with more advanced tumors, where treatment goals are palliation and extending survival. With multiple new and promising treatment options emerging for these patients, the challenge for the medical oncologist is how best to integrate these therapies into routine clinical practice. Here we review the most recent data on the efficacy and safety of yttrium-90 radioembolization in HCC, the considerations involved in patient selection, and the optimal assessment and management of patients receiving treatment. We also examine the potential impact of several ongoing clinical trials.

Multicenter evaluation of the safety and efficacy of radioembolization in patients with unresectable colorectal liver metastases selected as candidates for (90)Y resin microspheres

BACKGROUND

Metastatic colorectal cancer liver metastases Outcomes after RadioEmbolization (MORE) was an investigator-initiated case-control study to assess the experience of 11 US centers who treated liver-dominant metastases from colorectal cancer (mCRC) using radioembolization [selective internal radiation therapy (SIRT)] with yttrium-90-((90)Y)-labeled resin microspheres.

METHODS

Data from 606 consecutive patients who received radioembolization between July 2002 and December 2011 were collected by an independent research organization. Adverse events (AEs) and survival were compared across lines of treatment using Fisher's exact test and Kaplan-Meier estimates, respectively.

RESULTS

Patients received a median of 2 (range, 0-6) lines of prior chemotherapy; 35.1% had limited extrahepatic metastases. Median tumor-to-liver ratio and -activity administered at first procedure were 15% and 1.17 GBq, respectively. Hospital stay was <24 hours in 97.8% cases. Common grade ≥3 AEs over 184 days follow-up were: abdominal pain (6.1%), fatigue (5.5%), hyperbilirubinemia (5.4%), ascites (3.6%) and gastrointestinal ulceration (1.7%). There was no statistical difference in AEs across treatment lines (P>0.05). Median survivals [95% confidence interval (CI)] following radioembolization as a 2(nd)-line, 3(rd)-line, or 4(th)-plus line were 13.0 (range, 10.5-14.6), 9.0 (range, 7.8-11.0), and 8.1 (range, 6.4-9.3) months, respectively; and significantly prolonged in patients with ECOG 0 vs. ≥1 (P=0.009). Statistically significant independent variables for survival at radioembolization were: disease stage [extrahepatic metastases, extent of liver involvement (tumor-to-treated-liver ratio)], liver function (uncontrolled ascites, albumin, alkaline phosphatase, aspartate transaminase), leukocytes, and prior chemotherapy.

CONCLUSIONS

Radioembolization appears to have a favorable risk/benefit profile, even among mCRC patients who had received ≥3 prior lines of chemotherapy.

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.

Yttrium-90 radioembolization vs sorafenib for intermediate-locally advanced hepatocellular carcinoma: a cohort study with propensity score analysis

BACKGROUND & AIMS

Sorafenib and transarterial (90) Y-radioembolization (TARE) are possible treatments for Barcelona Clinic Liver Cancer (BCLC) intermediate-advanced stage hepatocellular carcinoma (HCC). No study directly comparing sorafenib and TARE is currently available. This single-centre retrospective study compares the outcomes achieved with sorafenib and TARE in HCC patients potentially amenable to either therapy.

METHODS

Seventy-four sorafenib (71 ± 10 years, male 87%, BCLC B/C 53%/47%) and 63 TARE HCC patients (66 ± 9 years, male 79%, BCLC B/C 41%/59%) were included based on the following criteria: Child-Pugh class A/B, performance status ≤1, HCC unfit for other effective therapies, no metastases and no previous systemic chemotherapy.

RESULTS

Median overall survivals of the two groups were comparable, being 14.4 months (95% CI: 4.3-24.5) in sorafenib and 13.2 months (95% CI: 6.1-20.2) in TARE patients, with 1-, 2- and 3-year survival rates of 52.1%, 29.3% and 14.7% vs 51.8%, 27.8% and 21.6% respectively. Two TARE patients underwent liver transplantation after successful down-staging. To minimize the impact of confounding factors on survival analysis, propensity model matched 32 patients of each group for median age, tumour gross pathology and the independent prognostic factors (portal vein thrombosis, performance status, Model for End Liver Disease). Even after matching, the median survival did not differ between sorafenib (13.1 months; 95% CI: 1.2-25.9) and TARE patients (11.2 months; 95% CI: 6.7-15.7), with comparable 1-, 2- and 3-year survival rates.

CONCLUSIONS

In cirrhotic patients with intermediate-advanced or not-otherwise-treatable HCC, sorafenib and TARE provide similar survivals. Down-staging allowing liver transplantation only occurred after TARE.

Transarterial radioembolization using yttrium-90 microspheres in the treatment of hepatocellular carcinoma: a review on clinical utility and developments

A selective intra-arterial liver injection using yttrium-90-loaded microspheres as sources for internal radiation therapy is a form of transarterial radioembolization (TARE). Current data from the literature suggest that TARE is effective in hepatocellular carcinoma (HCC) and is associated with a low rate of adverse events; however, they are all based on retrospective series or non-controlled prospective studies, since randomized controlled trials comparing the other liver-directed therapies for intermediate and locally advanced stages HCC are still ongoing. The available data show that TARE provides similar or even better survival rates. TARE is very well tolerated and has a low rate of complications; these complications do not result from the embolic effects but mainly from the unintended irradiation to non-target tissue, including the liver parenchyma. The complications can be further reduced by accurate patient selection and a strict pre-treatment evaluation, including dosimetry and assessment of the vascular anatomy. First-line TARE is best indicated for intermediate-stage patients (according to the Barcelona Clinic Liver Cancer [BCLC] staging classification) who are poor candidates for transarterial chemoembolization or patients having locally advanced disease with segmental or lobar branch portal vein thrombosis. Moreover, data are emerging regarding the use of TARE in patients classified slightly above the criteria for liver transplantation with the purpose of downstaging them. TARE can also be applied as a second-line treatment in patients progressing to transarterial chemoembolization or sorafenib; a large number of Phase II/III trials are in progress in order to evaluate the best association with systemic therapies. Given the complexity of a correct treatment algorithm for potential TARE candidates and the need for clinical guidance, a comprehensive review was carried out analyzing both the best selection criteria of patients who really benefit from TARE and the new advances of this therapy which add significant value to the therapeutic weaponry against HCC.

Chemoembolization and radioembolization

Chemoembolization and radioembolization are at the core of the treatment of patients with hepatocellular carcinoma who cannot receive potentially curative therapies such as transplantation, resection or percutaneous ablation. They differ in the mechanism of action (ischaemia and increase cytotoxic drug exposure for chemoembolization, internal irradiation for radioembolization) and may target different patient populations. Chemoembolization with cytotoxic drug-eluting beads is a more standardized although not necessarily more effective way of performing chemoembolization. Cytoreduction is achieved in most patients but complete tumor ablation may be achieved and lead to extended survival. Grade 1 level of evidence support the use of chemoembolization for the treatment of patients in the early and intermediate stages while grade 2 evidence supports the use of radioembolization for the treatment of patients in intermediate to advanced stages. Selecting the best candidates for both techniques is still a work in progress that ongoing clinical trials are trying to address.

[18F]Fluorodeoxyglucose PET for Interventional Oncology in Liver Malignancy

[(18)F]Fluorodeoxyglucose (FDG) PET is a functional imaging tool that provides metabolic information, which has the potential to detect a lesion before it becomes anatomically apparent. This ability constitutes a strong argument for using FDG-PET/computed tomography (CT) in the management of oncology patients. Many studies have investigated the accuracy of FDG-PET or FDG-PET/CT for these purposes, but with small sample sizes based on retrospective cohorts. This article provides an overview of the role of FDG-PET or FDG-PET/CT in patients with liver malignancies treated by means of surgical resection, ablative therapy, chemoembolization, radioembolization, and brachytherapy, all being liver-directed oncologic interventions.

Radioembolization for colorectal cancer liver metastases: current role and future opportunities – the medical oncologist’s perspective

SUMMARY 

The liver is the most common and often the only site of metastatic disease in patients with metastatic colorectal cancer. For patients who do not have resectable disease, a number of liver-directed therapies are increasingly being used in routine clinical practice, including yttrium-90 radioembolization. The challenge for the medical oncologist is how best to integrate this promising new option into routine practice in the setting of ever-evolving standard systemic therapy options. Here we review the most recent data on the efficacy and safety of yttrium-90, considerations when selecting patients for treatment and we examine the potential impact of current clinical trials.

Phase I study of capecitabine combined with radioembolization using yttrium-90 resin microspheres (SIR-Spheres) in patients with advanced cancer

BACKGROUND

This was a prospective single-centre, phase I study to document the maximum tolerated dose (MTD), dose-limiting toxicity (DLT), and the recommended phase II dose for future study of capecitabine in combination with radioembolization.

METHODS

Patients with advanced unresectable liver-dominant cancer were enrolled in a 3+3 design with escalating doses of capecitabine (375-1000 mg/m(2) b.i.d.) for 14 days every 21 days. Radioembolization with (90)Y-resin microspheres was administered using a sequential lobar approach with two cycles of capecitabine.

RESULTS

Twenty-four patients (17 colorectal) were enrolled. The MTD was not reached. Haematologic events were generally mild. Common grade 1/2 non-haematologic toxicities included transient transaminitis/alkaline phosphatase elevation (9 (37.5%) patients), nausea (9 (37.5%)), abdominal pain (7 (29.0%)), fatigue (7 (29.0%)), and hand-foot syndrome or rash/desquamation (7 (29.0%)). One patient experienced a partial gastric antral perforation with a capecitabine dose of 750 mg/m(2). The best response was partial response in four (16.7%) patients, stable disease in 17 (70.8%) and progression in three (12.5%). Median time to progression and overall survival of the metastatic colorectal cancer cohort was 6.4 and 8.1 months, respectively.

CONCLUSIONS

This combined modality treatment was generally well tolerated with encouraging clinical activity. Capecitabine 1000 mg/m(2) b.i.d. is recommended for phase II study with sequential lobar radioembolization.

Radioembolization of hepatic tumors

Unresectable primary and metastatic liver tumors are a leading cause of cancer mortality and morbidity. This remains a challenging and key task for every oncologist despite significant advances that have been made with selective targeted systemic agents and in technology advances with radiotherapy delivery. Radioembolization (RE) is a technique of permanently implanting microspheres containing Yttrium-90 ((90)Y), a beta-emitting isotope with a treatment range of 2 mm, into hepatic tumors. This form of brachytherapy utilizes the unique dual vascular anatomy of the liver to preferentially deliver radioactive particles via the hepatic artery to tumor, sparing normal liver parenchyma. The main treatment inclusion criteria are patients with solid tumors, compensated liver functions, life expectancy of at least three months, and ECOG performance status 0-2. Benefit of RE has been proven in patients that have low-to-moderate extrahepatic disease burden, prior liver radiotherapy, heavy prior chemotherapy and biologic agent exposure, and history of hepatic surgery or ablation. Most of the clinical evidence is reported in metastatic colorectal, and neuroendocrine tumors (NET), and primary hepatocellular cancer. A growing body of data supports the use of RE in hepatic metastatic breast cancer, intrahepatic cholangiocarinoma, and many other metastatic tumor types. Side effects are typically mild constitutional and GI issues limited to the first 7-14 days post treatment, with only 6% grade 3 toxicity reported in large series. Potentially serious or fatal radiation induced liver disease is extremely rare, reported in only 1% or fewer in major series of both metastatic and primary tumors treated with RE. Currently, high priority prospective clinical trials are testing RE combined with chemotherapy in first line therapy for colorectal hepatic metastases, and combined with sorafenib for hepatocellular carcinomas (HCCs). Fortunately, this beneficial and now widely available therapy is being increasingly incorporated into the standard therapy algorithms of multidisciplinary GI cancer teams worldwide. This form of radiotherapy differs significantly from daily external beam radiotherapy in many ways, particularly in dose rate, dosimetric coverage and duration of radiation delivery, side effects, and patient selection factors. A wealth of experience using RE in solid tumors exists and ongoing major prospective clinical trials will soon clarify the role of RE in the management of metastatic colorectal liver metastases.

Radioembolization with Yttrium-90 microspheres (SIRT) in pancreatic cancer patients with liver metastases: efficacy, safety and prognostic factors

OBJECTIVE

To analyze the clinical efficacy of (90)Y radioembolization in liver metastases from pancreatic cancer, to describe treatment toxicities and to identify biomarkers as predictors of outcome.

METHODS

Data from 19 pancreatic cancer patients (9 females/10 males) who had received (90)Y radioembolization for metastatic liver disease between 06/2004 and 01/2011 were analyzed retrospectively.

RESULTS

The median age at (90)Y radioembolization was 63 years (range 43-77). In 16 patients, previous palliative gemcitabine-based chemotherapy was given for metastatic disease. Objective response in the liver after (90)Y radioembolization was 47%. Median local progression-free survival in the liver was 3.4 months (range 0.9-45.0). Median overall survival (OS) was 9.0 months (range 0.9-53.0) and 1-year survival was 24%. Cox regression models for baseline biomarkers at (90)Y radioembolization revealed correlations of increased carbohydrate antigen 19-9 (p = 0.02) and C-reactive protein (p = 0.03) with shorter OS. Short-term adverse events (nausea, vomiting, fatigue, fever and abdominal pain) did not exceed grade 3. As long-term adverse events, liver abscesses, gastroduodenal ulceration, cholestasis and cholangitis, ascites and spleen infarction were observed.

CONCLUSION

(90)Y radioembolization is able to induce an encouraging local response rate of liver metastases of pancreatic cancer patients. Most short-term toxicities are manageable; however, patients should be followed up carefully for severe long-term toxicities.

A new model to estimate prognosis in patients with hepatocellular carcinoma after Yttrium-90 radioembolization

Aims

The current prognostic model to estimate the survival in hepatocellular carcinoma (HCC) patients treated with transarterial hepatic selective internal radiotherapy (SIRT) is not fully characterized. The aim of this study was to establish a new scoring model including assessment of both tumor responses and therapy-induced systemic changes in HCC patients to predict survival at an early time point post-SIRT.

Methods and materials

Between 2008 and 2012, 149 HCC patients treated with SIRT were included into this study. CT images and biomarkers in blood tested at one month post-SIRT were analyzed and correlated with clinical outcome. Tumor responses were assessed by RECIST 1.1, mRECIST, and Choi criteria. Kaplan-Meier methods were used to estimate survival curves. Cox regression was used in uni- and multivariable survival analyses and in the establishment of a prognostic model.

Results

A multivariate proportional hazards model was created based on the tumor response, the number of tumor nodules, the score of the model for end stage liver disease (MELD), and the serum C-reactive protein levels which were independent predictors of survival in HCC patients at one month post-SIRT. This prognostic model accurately differentiated the outcome of patients with different risk scores in this cohort (P<0.001). The model also had the ability to assign a predicted survival probability for individual patients.

Conclusions

A new model to predict survival of HCC patients mainly based on tumor responses and therapy-induced systemic changes provides reliable prognosis and accurately discriminates the survival at an early time point after SIRT in these patients.

Prognostic utility of 90Y radioembolization dosimetry based on fusion 99mTc-macroaggregated albumin-99mTc-sulfur colloid SPECT

Planning hepatic (90)Y radioembolization activity requires balancing toxicity with efficacy. We developed a dual-tracer SPECT fusion imaging protocol that merges data on radioactivity distribution with physiologic liver mapping.

METHODS

Twenty-five patients with colorectal carcinoma and bilobar liver metastases received whole-liver radioembolization with resin microspheres prescribed as per convention (mean administered activity, 1.69 GBq). As part of standard treatment planning, all patients underwent SPECT imaging after intraarterial injection of 37 MBq of (99m)Tc-macroaggregated albumin ((99m)Tc-MAA) to simulate subsequent (90)Y distribution. Immediately afterward, patients received 185 MBq of labeled sulfur colloid ((99m)Tc-SC) intravenously as a biomarker for normal hepatic reticuloendothelial function and SPECT was repeated. The SPECT images were coregistered and fused. A region-based method was used to predict the (90)Y radiation absorbed dose to functional liver tissue (DFL) by calculation of (99m)Tc-MAA activity in regions with (99m)Tc-SC uptake. Similarly, the absorbed dose to tumor (DT) was predicted by calculation of (99m)Tc-MAA activity in voxels without (99m)Tc-SC uptake. Laboratory data and radiographic response were measured for 3 mo, and the survival of patients was recorded. SPECT-based DT and DFL were correlated with parameters of toxicity and efficacy.

RESULTS

Toxicity, as measured by increase in serum liver enzymes, correlated significantly with SPECT-based calculation of DFL at all time points (P < 0.05) (mean DFL, 27.9 Gy). Broad biochemical toxicity (>50% increase in all liver enzymes) occurred at a DFL of 24.5 Gy and above. In addition, in uni- and multivariate analysis, SPECT-based calculation of DT (mean DT, 44.2 Gy) correlated with radiographic response (P < 0.001), decrease in serum carcinoembryonic antigen (P < 0.05), and overall survival (P < 0.01). The cutoff value of DT for prediction of 1-y survival was 55 Gy (area under the receiver-operating-characteristic curve = 0.86; P < 0.01). Patients who received a DT of more than 55 Gy had a median survival of 32.8 mo, compared with 7.2 mo in patients who received less (P < 0.05).

CONCLUSION

Dual-tracer (99m)Tc-MAA-(99m)Tc-SC fusion SPECT offers a physiology-based imaging tool with significant prognostic power that may lead to improved personalized activity planning.

Splenomegaly-associated thrombocytopenia after hepatic yttrium-90 radioembolization

PURPOSE

Thrombocytopenia is often observed after yttrium-90 radioembolization (RE). Possible mechanisms include radiation toxicity to the bone marrow, consumption in the liver due to local radiation effects, and sequestration in the spleen. We sought to identify the causative factors.

MATERIALS AND METHODS

Patients with complete baseline and 3-month post-RE imaging and laboratory data were included in this retrospective analysis. Univariate and multivariate regression analyses were performed on clinical, procedural, and imaging data.

RESULTS

A total of 116 patients were identified (65 male, 51 female; median age 64 years). Forty-six patients were treated for primary and 70 for metastatic liver malignancy. Of these, 86 were treated with resin and 30 with glass microspheres; median activity was 1.85 GBq. Eighty-three patients underwent whole-liver treatment. Maximum individual change in platelet count was -20.2 % leading to new or increased grade of thrombocytopenia in 48 patients (41.4 %) by National Cancer Institute Common Toxicity Criteria for Adverse Events version 4.02 criteria. Independent risk factors for decreased platelet count included change in spleen volume (median change +17.5 %; p = 0.001) and whole-liver (rather than lobar or segmental) treatment (p = 0.025). Administered activity and absorbed dose were not associated with change in platelet count. The change in spleen volume itself was associated with previous epidermal growth factor receptor-inhibitor treatment (p = 0.002), whole-liver absorbed dose (p = 0.027), and multiple-line chemotherapy (0.012) for whole-liver treatments only.

CONCLUSION

Post-RE treatment increase of spleen volume is correlated with decreased peripheral platelet count suggesting a mechanism of increased portal hypertension and hypersplenism being responsible.

Comparison of the survival and tolerability of radioembolization in elderly vs. younger patients with unresectable hepatocellular carcinoma

BACKGROUND & AIMS

The European Network on Radioembolization with Yttrium-90 resin microspheres study group (ENRY) conducted a retrospective study to evaluate the outcomes among elderly (≥ 70 years) and younger patients (<70 years) with unresectable hepatocellular carcinoma (HCC) who received radioembolization at 8 European centers.

METHODS

Patients with confirmed diagnosis of unresectable HCC who either progressed following resection or locoregional treatment and/or who were considered poor candidates for chemoembolization were evaluated by a multidisciplinary team for radioembolization with (90)Y-resin microspheres (SIR-Spheres; Sirtex Medical). The survival outcome and all adverse events were compared between the two age groups.

RESULTS

Between 2003 and 2009, 128 elderly and 197 younger patients received radioembolization. Patients in both groups had similar demographic characteristics. Many elderly and younger patients alike had multinodular, BCLC stage C disease, invading both lobes (p = 0.648). Elderly patients had a lower tumor burden, a smaller median target liver volume (p = 0.016) and appeared more likely to receive segmental treatment (p = 0.054). Radioembolization was equally well tolerated in both cohorts and common procedure-related adverse events were predominantly grade 1-2 and of short duration. No significant differences in survival between the groups were found (p = 0.942) with similar median survival in patients with early, intermediate or advanced BCLC stage disease.

CONCLUSIONS

Radioembolization appears to be as well-tolerated and effective for the elderly as it is for younger patients with unresectable HCC. Age alone should not be a discriminating factor for the management of HCC patients.