Hepatic Arterial Yttrium 90 Microspheres: Another Treatment Option for Hepatocellular Carcinoma

Current role of selective internal irradiation with yttrium-90 microspheres in the management of hepatocellular carcinoma: a systematic review

PURPOSE

This article reviews the role of selective internal irradiation (SIR) with yttrium-90 ((90)Y) microspheres for hepatocellular carcinoma (HCC).

METHODS AND MATERIALS

Studies were identified by searching Medline and PubMed databases for articles from 1990 to 2009 using the keywords "selective internal irradiation," "hepatocellular carcinoma," "therapeutic embolization," and "yttrium-90."

RESULTS

(90)Y microspheres are a safe and well-tolerated therapy for unresectable HCC (median survival range, 7 -21.6 months). The evidence was limited to cohort studies and comparative studies with historical control. (90)Y microspheres have been reported to downstage unresectable HCC to allow for salvage treatments with curative intent, act as a bridging therapy before liver transplantation, and treat HCC with curative intent for patients who are not surgical candidates because of comorbidities.

CONCLUSIONS

(90)Y microsphere is recommended as an option of palliative therapy for large or multifocal HCC without major portal vein invasion or extrahepatic spread. It can also be used for recurrent unresectable HCC, as a bridging therapy before liver transplantation, as a tumor downstaging treatment, and as a curative treatment for patients with associated comorbidities who are not candidates for surgery.

Intra-arterial therapies for hepatocellular carcinoma: where do we stand?

PURPOSE AND DESIGN

Intra-arterial therapies for unresectable hepatocellular carcinoma (HCC) consist of a catheter-based group of treatments where therapeutic and/or embolic agents are intra-arterially directed to target tumors. Here we review these therapies, which may be classified into embolotherapy/chemotherapy-based and radiotherapy-based treatments. Embolotherapy/chemotherapy-based treatments include transcatheter arterial embolization, transarterial chemoembolization, transcatheter arterial chemoeinfusion, and chemoembolization with drug-eluting beads. Radiotherapy-based treatments include radioembolization with yttrium-90 and injection of iodine-131-labeled lipiodol.

RESULTS AND CONCLUSION

Interpretation of the results of clinical trials as well as implementation of meta-analyses involving the efficacy of intra-arterial therapies for unresectable HCC has been challenging and difficult to perform. The levels of evidence for treatment recommendations in oncology provide a common framework to understand the current status of intra-arterial therapies for HCC. Here we use an evidence-based approach to critically review and comprehend the current role and future potential of intra-arterial therapies in unresectable HCC.

Clinical and imaging experience with yttrium-90 microspheres in the management of unresectable liver tumours

INTRODUCTION

Selective internal radiation therapy (SIRT) is emerging as a new therapeutic modality in recent years for management of non-resectable hepatic malignancies. Our experience in clinical application of this treatment is reported here.

MATERIAL AND METHODS

From June 2004, patients whose liver tumours were no longer amenable for any conventional treatment with either chemotherapy or surgery were considered for yttrium-90 microspheres treatment after discussion at our multidisciplinary meeting. A pre-treatment planning was carried out with visceral angiography and technetium-99m macroaggregated albumin (MAA) for assessment of both tumour volume and extrahepatic shunting in addition to a baseline PET and CT scans, respectively. Two weeks later, a second visceral angiogram was performed to deliver the calculated dosage of microspheres into the arterial system supplying the tumour. Patients were then followed up with tumour markers, repeat PET and CT scans of abdomen at 6 weeks and 3 monthly thereafter.

RESULT

Twenty-one patients (F=11, M=10; age range 40-75 years, mean=58 years) received yttrium-90 microspheres consisting of liver metastases from colorectal primary (n=10) and non-colorectal primaries (n=8), and primary liver tumours (n=3). One patient received 2 treatments. The mean administered activity of microspheres delivered was 1.9 GBq (range 1.2-2.5 GBq). Injection of microspheres had no immediate effect on either clinical haematology or liver function tests. At follow-up, 86% of patients showed decreased activity on PET scan at 6 weeks (p=0.01). The mean pre-treatment SUV was 12.2+/-3.7 and the mean post-treatment SUV was 9.3+/-3.7, indicating a significant improvement measured with PET activity. Only 13% showed a reduction in the size of tumour on CT scan. For patients with colorectal liver metastases, there was no significant reduction in CEA level (127+/-115 vs 75+/-72 micro/l, p=0.39). Complications were seen in 4 patients (19%) including radiation hepatitis (n=2), cholecystitis (n=1) and duodenal ulceration (n=1). All resolved without surgical intervention. Seven patients died at follow-up from progressive extrahepatic disease (33%).

CONCLUSION

SIRT should be considered for patients with advanced liver cancer. It has a significant effect on liver disease in the absence of extrahepatic disease. PET imaging has an integral role in the assessment of patients treated with yttrium-90 SIR-Spheres.

Management and prevention of adverse effects related to treatment of liver tumours with 90Y microspheres

BACKGROUND AND AIM

Selective internal radiation therapy with 90Y microspheres (SIR spheres) is increasingly used in the treatment of extensive liver tumours. Careful selection and preparation of patients are necessary to avoid possible adverse effects. We aimed to evaluate the incidence and severity of adverse effects resulting from the administration of SIR spheres during therapy.

MATERIALS AND METHODS

Between June 2004 and August 2006, 21 patients (11 women and 10 men; age range 40-75 years; mean, 58 years) with a wide range of extensive liver tumours were treated with SIR spheres. The mean administered dose was 1.87 GBq (range 1.2-2.5 GBq). During the follow-up period of 26 months, all adverse effects were monitored and classified according to the National Cancer Institute criteria.

RESULTS

Four patients had adverse effects: one case of cholecystitis followed by fibrosis and portal hypertension, one case of peptic ulceration and two cases of radiation hepatitis. All cases responded to appropriate therapy.

CONCLUSION

Proper selection of patients and accurate interpretation of pre-treatment investigations are vital for minimizing adverse effects following therapy with SIR spheres. In our experience, all adverse effects were moderate with no life-threatening consequences.

Radioembolization with yttrium-90 microspheres: a state-of-the-art brachytherapy treatment for primary and secondary liver malignancies: part 3: comprehensive literature review and future direction

Treatment options for primary and secondary liver tumors that cannot be resected or ablated are based on transarterial techniques. Although the majority of these are based on bland and chemoembolization techniques, yttrium-90 microspheres represent an alternate transarterial option. Although the amount of literature on (90)Y does not rival that of bland or chemoembolization, there nevertheless are ample data that support its use for primary and metastatic liver tumors. A comprehensive review of the entire available literature dating from the early 1960s is presented, as is a discussion of the possibilities for future research with use of radioembolization as a platform.

Yttrium-90 microspheres for the treatment of hepatocellular carcinoma: a review

To present a critical review of yttrium-90 (TheraSphere) for the treatment of hepatocellular carcinoma (HCC). Medical literature databases (Medline, Cochrane Library, and CANCERLIT) were searched for available literature concerning the treatment of HCC with TheraSphere. These publications were reviewed for scientific and clinical validity. Studies pertaining to the use of yttrium-90 for HCC date back to the 1960s. The results from the early animal safety studies established a radiation exposure range of 50-100 Gy to be used in human studies. Phase I dose escalation studies followed, which were instrumental in delineating radiation dosimetry and safety parameters in humans. These early studies emphasized the importance of differential arteriolar density between hypervascular HCC and surrounding liver parenchyma. Current trends in research have focused on advancing techniques to safely implement this technology as an alternative to traditional methods of treating unresectable HCC, such as external beam radiotherapy, conformal beam radiotherapy, ethanol ablation, trans-arterial chemoembolization, and radiofrequency ablation. Yttrium-90 (TheraSphere) is an outpatient treatment option for HCC. Current and future research should focus on implementing multicenter phase II and III trials comparing TheraSphere with other therapies for HCC.