Use of yttrium-90 microspheres (TheraSphere) in a patient with unresectable hepatocellular carcinoma leading to liver transplantation: a case report

Review of Use of Y90 as a Bridge to Liver Resection and Transplantation in Hepatocellular Carcinoma

BACKGROUND

The incidence of hepatocellular carcinoma (HCC) has been rising, and 80% of HCCs are unresectable at the time of presentation. In recent years, Yttrium-90 (Y90) radioembolization has arisen as a potential tool to treat the primary HCC tumor while also inducing contralateral liver hypertrophy to increase future liver remnant volumes. The goal of this multidisciplinary review is to summarize the contemporary evidence on the safety, efficacy, and utility of Y90 as a bridge to liver resection and transplant in patients with HCC.

METHODS

A narrative review was conducted of the recent literature regarding the utilization of Y90 as a therapy prior to liver resection or transplant in patients with HCC. A specific emphasis was placed on articles published in the last 10 years.

RESULTS

Y90 radioembolization has demonstrated a high safety profile and increasing utility in bridging and downstaging patients with HCC who subsequently undergo liver resection or transplant. The continuous advancements in treatment strategies and radiation dosimetry have paved the way for the incorporation of Y90 in all stages of HCC with different intents, including downstaging and bridging.

CONCLUSIONS

Y90 radioembolization can be safely used in the HCC population to bridge patients to resection or transplantation, induce future liver remnant growth, and select for less aggressive tumor biology prior to surgery.

Trans-arterial radio-embolization: a new chance for patients with hepatocellular cancer to access liver transplantation, a world review

Liver transplantation (LT) for hepatocellular carcinoma (HCC) within the Milan criteria (MC) is nowadays a curative procedure. Yttrium-90 microspheres radioembolization (Y90-RE) has shown to be an effective and safe treatment of primary liver tumors. The aim of this work is to offer a view on the publications which report on the use of Y90-RE as bridge or downstaging prior to LT. Twenty articles have been considered for this world review. About 178 LT in patients were treated with Y90-RE prior to LT. Most of patients had a downstaging strategy. In all series alpha-fetoproteins decreased between Y90-RE and LT. Therefore, Y90-RE may have an important role in the bridge and downstaging treatments.

Yttrium-90 Radioembolization for Hepatocellular Carcinoma Prior to Liver Transplantation

BACKGROUND

Liver transplantation (LT) is a well-established procedure for hepatocellular carcinoma (HCC) within the Milan criteria. Yttrium-90 microspheres radioembolization (Y90-RE) has shown to be an effective and safe treatment of primary liver tumors. We retrospectively evaluate the efficacy of the Y90-RE in patients with HCC prior to LT.

METHODS

From January 2002 to December 2015, 365 patients were transplanted at the San Camillo Hospital Center. One hundred forty-three patients were transplanted for HCC, and in 22 cases the patients were treated with Y90-RE before LT.

RESULTS

Three patients were treated with Y90-RE within the Milan criteria, and 19 patients were out of criteria before Y90-RE. Four patients had an increasing MELD score between Y90-RE and LT. On the other hand, alpha-fetoprotein decreases after Y90-RE treatment in all cases. No patient death was observed in Y90-RE procedure or at LT. In 78.9 % of cases, a successful downstaging was observed, and in 100 % of cases bridging was achieved. From Y90-RE treatment overall survival was 43.9 months. From LT, overall mean survival was 30.2 months with a free survival of 29.6 months. The overall survival after LT analysis between the patients treated with Y90-RE and patients without was not significant (p = 0.113). Free survival analysis was not significant (p = 0.897) between the two populations.

CONCLUSIONS

We successfully performed LT in patients after Y90-RE treatment both as bridging and downstaging for HCC and obtained a similar overall and free survival of LT for HCC within Milan criteria. Y90-RE becomes a real option to provide curative therapy for patients who traditionally are not considered eligible for surgery.

Long-Term Outcome After Liver Transplantation for Hepatocellular Carcinoma Following Yttrium-90 Radioembolization Bridging Treatment

Background

Bridging treatments are employed in liver transplant waitlist patients with hepatocellular carcinoma (HCC) because of the risk of tumor progression during the waiting time. Radioembolization is mostly employed in the control of large or multifocal HCCs when other locoregional treatment modalities cannot be applied because of the number or size of lesions. The purpose of this study was to evaluate our experience with the use of radioembolization as a bridge to transplantation and its effect on tumor recurrence and survival after liver transplantation.

Material/Methods

A retrospective review of 40 consecutive patients with HCC who underwent liver transplantation after radioembolization bridging treatment between January 2007 and December 2015 at the University Hospital Essen, Germany, was performed. Patients’ characteristics, alpha-fetoprotein (AFP) levels, pathologic tumor response, tumor recurrence rate, and survival rates were examined through chart review.

Results

Histopathological examination of the explanted liver specimen revealed complete tumor necrosis in 17 specimens, partial necrosis in 18 specimens, and no significant necrosis in five specimens. Median overall survival was 46 months. Nine patients developed recurrent HCC. Median time from liver transplantation to diagnosis of tumor recurrence was 15 months. There was a trend towards a lower risk of tumor recurrence for patients with complete necrosis on explant specimens. Patients with tumor recurrence demonstrated statistically significantly higher pre- and post-treatment AFP levels (p=0.0234 and p=0.0236) and statistically significantly more frequently microvascular invasion (p=0.0163).

Conclusions

Histopathological assessment of explanted livers revealed at least partial necrosis in 87.5% of patients. Patients with successful bridging treatment, i.e. complete necrosis of explant specimens, demonstrate a trend towards a lower risk of tumor recurrence.

The role of 90Y-radioembolization in downstaging primary and secondary hepatic malignancies: a systematic review

Radioembolization (RE) is an emerging treatment strategy for patients with primary hepatic malignancies and metastatic liver disease. Though RE is primarily performed in the palliative setting, a shift toward the curative setting is seen. Currently, hepatic resection and in selected cases liver transplantation are the only curative options for patients with a hepatic malignancy. Unfortunately, at diagnosis most patients are not eligible for liver surgery due to the imbalance between the necessary liver resection and the remaining liver remnant. However, in borderline resectable cases, tumor volume reduction and/or increasing the future liver remnant can lead to a resectable situation. The combination of selective tumor treatment, the induction of hypertrophy of untreated liver segments, and its favourable toxicity profile make RE an appealing strategy for downstaging. The present review discusses the possibilities for RE in the preoperative setting as a downstaging tool or as a bridge to liver transplantation.

Radioembolization using yttrium-90 microspheres as bridging and downstaging treatment for unresectable hepatocellular carcinoma before liver transplantation: initial single-center experience

INTRODUCTION

HCC is the sixth most common malignancy worldwide and is the third most common cause of cancer related mortality. Moreover, the incidence of HCC is increasing. Surgical treatments for HCC including resection and/or transplantation provide the best curative outcomes in early stages. Unfortunately, many patients present at an advanced stage. Currently, locoregional therapies have an emerging role in the management of HCC for bridging to liver transplantation and for downstaging the disease to within transplant criteria. Radioembolization is among commonly used locoregional therapies.

OBJECTIVE

To describe our initial experience with the use of Therasphere® as bridging or downstaging modality before liver transplantation, including our institutional indications, technique and outcome.

MATERIALS AND METHODS

We retrospectively examined our database for liver transplantation after the use of Therasphere®. Nine patients were identified and reported.

RESULTS

They were 5 females and 4 males. Their current age range is 40-72 years with a mean of 53.8 ± 9.5 years. Three patients had Therasphere® as downstaging treatment to our institutional transplantation criteria. Our institution is using UCSF criteria as a cut off limit for liver transplantation as primary treatment modality. The other 6 patients had Therasphere® as bridging for liver transplantation especially when other modalities are not possible. None of these lesions were treated by any other locoregional treatment before or after Therasphere®. Follow-up after liver transplantation ranged between 3.7 and 60.1 months (mean of 15.8 ± 17.7 months). All patients are still living, no retransplantation was done and none of them showed evidence of disease recurrence (100% graft, patient and disease free survival).

CONCLUSION

Our initial experience showed that Therasphere® is a promising therapeutic tool for both downstaging and bridging of HCC before liver transplant.

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.

Partial liver volume radioembolization induces hypertrophy in the spared hemiliver and no major signs of portal hypertension

BACKGROUND

Post-treatment contralateral hemiliver hypertrophy has created an interest in lobar liver radioembolization (RE) as a pre-surgery tool.

METHODS

Liver and spleen volumes and function were studied in 83 patients submitted to partial liver volume RE at 4-8 weeks (T1), 10-26 weeks (T2), and >26 weeks (T3) after RE.

RESULTS

More than half of the patients had cirrhosis with hepatocellular carcinoma. The main finding was a progressive increase in the volume of the spared hemiliver (mean absolute increase at T3: 230 ml). The percentage of patients in whom the baseline ratio of spared volume to total liver volume was <40% dropped from 56.6% at baseline to 29.4% at T2 (P < 0.001). A significant and progressive increase in spleen volume but not in portal vein diameter was also observed. A small percentage of patients developed hypersplenism, mostly those without cirrhosis (16.0% at T2). Six patients (five with portal vein thrombosis, cirrhosis or both) developed signs of portal hypertension by T2.

CONCLUSIONS

The present results warrant further studies to better elucidate the mechanism underlying this phenomenon of spared hemiliver hypertrophy and to investigate its role as an alternative to portal vein embolization in the management of patients with potentially resectable liver tumours.

Radioembolization for hepatocellular carcinoma

Radioembolization is a form of brachytherapy in which intra-arterially injected (90)Y-loaded microspheres serve as sources for internal radiation purposes. It produces average disease control rates above 80% and is usually very well tolerated. Main complications do not result from the microembolic effect, even in patients with portal vein occlusion, but rather from an excessive irradiation of non-target tissues including the liver. All the evidence that support the use of radioembolization in HCC is based on retrospective series or non-controlled prospective studies. However, reliable data can be obtained from the literature, particularly since the recent publication of large series accounting for nearly 700 patients. When compared to the standard of care for the intermediate and advanced stages (transarterial embolization and sorafenib), radioembolization consistently provides similar survival rates. Two indications seem particularly appealing in the boundaries of these stages for first-line radioembolization. First, the treatment of patients straddling between the intermediate and advanced stages (intermediate patients with bulky or bilobar disease that are considered poor candidates for TACE, and advanced patients with solitary tumors invading a segmental or lobar branch of the portal vein). Second, the treatment of patients that are slightly above the criteria for resection, ablation or transplantation, for which downstaging could open the door for a radical approach. Radioembolization can also be used to treat patients progressing to TACE or sorafenib. With a number of clinical trials underway, the available evidence shows that it adds a significant value to the therapeutic weaponry against HCC of tertiary care centers dealing with this major cancer problem.

Yttrium-90 radioembolization of hepatocellular carcinoma and metastatic disease to the liver

Yttrium-90 ((90)Y) radioembolization is a catheter-based therapy that delivers internal radiation to hepatic tumors in the form of microspheres. (90)Y can be delivered to the hepatic tumor as either a constituent of a glass microsphere, TheraSphere(®), or as a biocompatible resin-based microsphere, SIR-Spheres(®). Once embedded within the tumor microcirculation, these microspheres emit β-radiation at therapeutic levels. While the technical aspects of radioembolization are quite complex, the collective clinical experience presented in the literature supports the use of (90)Y radioembolization for unresectable hepatic malignancies.

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.

Radioembolization (yttrium-90 microspheres) for primary and metastatic hepatic malignancies

Radioembolization using radioactive yttrium-90-labeled microspheres is gaining a stronger foothold in the management of primary and metastatic hepatic cancers. The expanding literature reveals good and encouraging results in both retrospective and prospective reports as demonstrated by low acute or late toxicity and high response rates. This treatment modality, which is most beneficial in patients with good liver reserve and low Eastern Cooperative Oncology Group performance status, has led to improved time to liver progression and extended overall patient survival. Although the phase III trials of radioembolization are ongoing as a first-line treatment of patients with metastatic colorectal cancer, there are sufficient phase II and retrospective clinical data supporting its use in salvage therapy for most patients. Patients with hepatocellular cancer, neuroendocrine tumors, and other primary sites, including breast and lung, have also shown promising response and survival increases in multi-institutional experiences.

Minimally invasive image-guided therapy for inoperable hepatocellular carcinoma: What is the evidence today?

Hepatocellular carcinoma (HCC) is a primary malignant tumor of the liver that accounts for an important health problem worldwide. Only 10-15% of HCC patients are suitable candidates for hepatic resection and liver transplantation due to the advanced stage of the disease at time of diagnosis and shortage of donors. Therefore, several minimally invasive image-guided therapies for locoregional treatment have been developed. Tumor ablative techniques are either based on thermal tumor destruction, as in radiofrequency ablation, cryoablation, microwave ablation, laser ablation and high-intensity focused ultrasound, or chemical tumor destruction, as in percutaneous ethanol injection. Image-guided catheter-based techniques rely on intra-arterial delivery of embolic, chemoembolic or radioembolic agents. These minimally invasive image-guided therapies have revolutionized the management of inoperable HCC. This review provides a description of all minimally invasive image-guided therapies currently available, an up-to-date overview of the scientific evidence for their clinical use, and thoughts for future directions.

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.

Radiologic findings following Y90 radioembolization for primary liver malignancies

A therapy gaining rapid clinical adoption involves radioembolization with the use of Yttrium-90 (90Y) microspheres. The 20-60 microm-sized microspheres are injected trans-arterially and flow to hepatic tumors given their preferential blood supply from the hepatic artery. Once they lodge in the arterioles, they impart a very intense local radiotherapeutic effect. Given the combined radiation and embolic effect, the imaging findings imparted by this mode of action differ significantly from other treatments. This work represents a comprehensive review of the imaging findings following radioembolization in patients with primary liver tumors. The report discusses imaging response, benign secondary effects, and complications. This should help educate the radiologist on imaging findings that should be expected following radioembolization and therefore aid in the proper image interpretation.

Is selective internal radioembolization safe and effective for patients with inoperable hepatocellular carcinoma and venous thrombosis?

BACKGROUND

The goal of this study was to examine the safety and efficacy of selective internal radioembolization (SIR) for hepatocellular carcinoma (HCC) with portal vein or caval thrombosis (VT), or both. Recent reports have demonstrated that SIR is safe for patients with HCC, but the impact on efficacy of venous thrombosis is unknown.

STUDY DESIGN

Prospective single-arm study of the use of Therasphere in patients with unresectable HCC enrolled from January 2004 to June 2007. Patients were categorized into three groups based on VT status and therapy.

RESULTS

Fifty-two patients were enrolled: 20 patients without VT who received SIR, 15 patients with VT who were treated, and 17 patients (10 with VT) who were not treated because of preprocedure screening failure. Fifty-eight treatments were administered, with a median of two treatments per patient (range of one to three treatments). Child's score was different between groups. Of the VT patients treated, 67% had portal VT, 7% had cava VT, and 26% had both. There were no treatment-related deaths. There was no difference in complications among groups (p = 0.34). Treated patients without thrombosis had a median overall survival of 13.9 months versus 2.7 months for those treated with thrombosis and 5.2 months for the untreated group given best supportive care only (p = 0.01).

CONCLUSIONS

SIR is safe in patients with HCC. Although SIR can be delivered with minimal morbidity, there might be no benefit for patients with VT. Continued emphasis on multimodality therapy in this population is needed to improve survival.

Radiofrequency ablation after selective internal radiation therapy with Yttrium90 microspheres in metastatic liver disease-Is it feasible?

This retrospective study analyzes, whether patients suffering from extensive hepatic metastatic disease treated with SIRT can become suitable candidates for RFA.Within 38 months 46 patients (26 female, 20 male; age 32-75 years) bearing an extensive hepatic metastatic disease were treated with SIRT. Patients suffered from metastases of breast cancer (16/46), colorectal cancer (CRC) (21/46), neuroendocrine (3/46), and other primary carcinomas (6/46). The indication for SIRT was otherwise untreatable metastases confined to the liver. Forty-three patients received single-session whole-liver radioembolization treatment using Yttrium90 resin microspheres with a mean activity of 2.13GBq. In 1 patient SIRT was confined to the left and in 2 patients to the right liver lobe. In 3 patients major complications (2/3 gastric ulceration and 1/3 oedematous pancreatitis) and in 24 patients minor complications occurred (acute abdominal/epigastric pain and/or nausea). Follow-up CT and/or MRI were obtained in 44 of 46 patients. In 5 of 44 patients tumor load decreased substantially (3/5 breast cancer, 1/5 CRC and 1/5 pancreatic cancer) making RFA feasible. The patients were referred for RFA after the first 3-month follow-up. RFA of the liver was successful in all cases in terms of complete ablation. In selected patients radioembolization is able to downstage liver metastases to an extent making a subsequent RFA suitable and therefore allows increasing the number of patients with a "complete response" after a minimally invasive therapy.

Selective or targeted gene/drug delivery for liver tumors: advantages and current status of local delivery

There are various disorders involving the liver. They include metabolic diseases, hepatitis, liver cirrhosis and cancer, the latter of which may be the most serious. Delivery of therapeutic genes or drugs should be targeted to either one of the following cells in the liver: hepatocytes, Kupffer cells and tumor endothelial cells, or to the tumor cells themselves. To maximize the therapeutic effect and minimize systemic toxicity or nontarget injuries, the sufficient amount or dose of genes or drugs should be specifically delivered to a target, with minimal exposure in their active forms to nontarget cells. There are diverse strategies to improve selective delivery or targeting efficiency. In this article, we present potential new therapeutic strategies and clinical developments for liver cancer, with a focus on the progress in the localized delivery of therapeutic agents using image-guided procedures.

Treatment of unresectable cholangiocarcinoma using yttrium-90 microspheres: results from a pilot study

BACKGROUND

The objective of this report was to present data from an open-label cohort study in which patients with intrahepatic cholangiocarcinoma (ICC) underwent radioembolization with yttrium-90 ((90)Y) microspheres.

METHODS

Twenty-four patients with histologically proven ICC were treated. The planned target dose was 120 Gray. Patients were stratified according to Eastern Cooperation Oncology Group (ECOG) performance status, tumor morphology (infiltrative vs peripheral), tumor distribution (solitary vs multifocal), and the presence or absence of portal vein thrombosis (PVT). Before and after the procedure, the following variables were assessed: 1) biochemical and clinical toxicity, 2) imaging (computed tomography/magnetic resonance imaging) response according to World Health Organization and European Association for the Study of Liver Disease (EASL) criteria, and 3) median survival after the first treatment using Kaplan-Meier methodology.

RESULTS

In total, 48 (90)Y treatments were administered to hepatic segments or lobes. Fatigue and transient abdominal pain were reported in 18 patients (75%) and 10 patients (42%), respectively. One patient (4%) developed grade 3 bilirubin toxicity. One patient (4%) developed a treatment-related gastroduodenal ulcer. On imaging follow-up of 22 patients, tumors demonstrated a partial response in 6 patients (27%), stable disease in 15 patients (68%), and progressive disease in 1 patient (5%). By using EASL guidelines, 17 patients (77%) showed >50% tumor necrosis on imaging follow-up. Two patients (9%) demonstrated 100% tumor necrosis. The median overall survival for the entire cohort (n = 24) was 14.9 months. The median survival for patients with an ECOG performance status of 0, 1, and 2 was 31.8 months, 6.1 months, and 1 month, respectively (P < .0001); the median survival for patients without and with PVT was 31.8 months and 5.7 months, respectively (P = .0003); and the median survival for patients with peripheral versus periductal-infiltrative tumors was 31.8 months and 5.7 months, respectively (P = .0005).

CONCLUSIONS

Radioembolization with (90)Y may be a therapeutic option for the treatment of unresectable ICC. Cancer 2008.

Radioembolization for the treatment of unresectable hepatocellular carcinoma: A clinical review

Hepatocellular carcinoma (HCC) is the sixth most common cancer in the world. The majority of patients with HCC present with unresectable disease. These patients have historically had limited treatment options secondary to HCC demonstrating chemoresistance to the currently available systemic therapies. Additionally, normal liver parenchyma has shown intolerance to tumoricidal radiation doses, limiting the use of external beam radiation. Because of these limitations, novel percutaneous liver-directed therapies have emerged. The targeted infusion of radioactive microspheres (radioembolization) represents one such therapy. Radioembolization is a minimally invasive transcatheter therapy through which radioactive microspheres are infused into the hepatic arteries that supply tumor. Once infused, these microspheres traverse the hepatic vascular plexus and selectively implant within the tumor arterioles. Embedded within the arterioles, the ⁹⁰Y impregnated microspheres emit high energy and low penetrating radiation doses selectively to the tumor. Radioembolization has recently shown promise for the treatment of patients with unresectable HCC. The objective of this review article is to highlight two currently available radioembolic devices (⁹⁰Y, ¹⁸⁸Rh) and provide the reader with a recent review of the literature.

Recent advances in transarterial therapy of primary and secondary liver malignancies

The management of liver malignancies presents many challenges. Few patients with primary hepatocellular carcinoma or metastatic disease of the liver are eligible for surgery, which is the only curative therapeutic option. Because the hepatic tumor burden is often a determinant of eligibility for surgery and is a primary contributor to morbidity and mortality, an increasing number of innovative techniques based on the transarterial administration of liver-directed drug-eluting or radiation-emitting microspheres are being tested for use in cytoreductive and palliative therapy. The delivery of therapy via a transarterial route takes advantage of the fact that hepatic malignancies are primarily supplied by the hepatic artery. The early results of clinical trials are promising; the clinical effectiveness and safety of drug-eluting and yttrium-90-bearing microspheres have been demonstrated; however, further clinical investigation is needed to verify a benefit in survival. Transarterially administered gene therapy holds promise but is still in the early stages of investigation. For all transarterial therapies, the outcome depends heavily on meticulous patient selection, careful preparation and administration of therapy, and early and regular follow-up evaluations by using an interdisciplinary approach.

Multimodality imaging following 90Y radioembolization: a comprehensive review and pictorial essay

Radioembolization with yttrium 90 (90Y) microspheres represents an emerging transarterial therapy for the treatment of liver malignancies that continues to generate interest in the medical community. The classic indication of treatment response is a reduction in tumor size; however, parenchymal changes (eg, necrosis, lack of enhancement, specific findings at positron emission tomography and functional magnetic resonance imaging) and other benign findings (pleural effusions, perivascular edema, contralateral hypertrophy, ring enhancement, perihepatic fluid, fibrosis) may occur following treatment, requiring proper image interpretation. With classic imaging findings and surrogates (time to progression, duration of response, disease-free interval), response rates range from 20% to 80% in patients treated for hepatocellular carcinoma or metastatic disease to the liver. Complications of 90Y radioembolization include cholecystitis, abscess, and bilomas and should be recognized early in the imaging follow-up of these patients. Radiologists who are involved in the posttreatment assessment of patients undergoing 90Y radioembolization should be familiar with the imaging findings and potential imaging pitfalls associated with this therapy.

Emerging approaches in hepatocellular carcinoma

The incidence of hepatocellular carcinoma (HCC) is predicted to continue to increase over the next 30 years. Surgical intervention, including resection and orthotopic liver transplantation (OLT) is offered to a limited number of patients. Novel approaches to the treatment of patients with HCC are needed. This article aims to review emerging approaches in the care of the HCC patient including systemic treatment, selection of appropriate candidates for OLT, improved imaging to follow treatment response, and management pre-OLT and post-OLT.

Is hepatic transplantation justified for primary liver cancer?

A concise, yet objective overview of Hepatocellular Carcinoma (HCC) treatment in 2006 with an intent to transplant is presented. The most significant variables impacting on the use of hepatic transplantation as therapy for primary liver cancer are developed under the headings of: Staging Criteria; Organ allocation; Transplant dropout minimization therapies; and Effects on the HCC general population. The pertinent medical literature and update of an ongoing intent-to-treat HCC with transplant single center randomized control trial are reviewed.

Complete eradication of hepatic metastasis from colorectal cancer by Yttrium-90 SIRT

Yttrium-90 (Y-90) radioembolization, also known as selective internal radiation therapy (SIRT), is a regional hepatic therapy used in the treatment of unresectable colorectal cancer (CRC) liver metastases. In SIRT, Y-90 impregnated microspheres are injected into the VASCULAR SUPPLY of hepatic tumor, leading to selective irradiation and necrosis of tumor TISSUE. While several studies demonstrate improved local control and survival with SIRT, the specific indications for this therapy have yet to be defined. Typically, SIRT is given in combination with chemotherapy as multimodal treatment for unresectable hepatic CRC. However, it HAS ALSO FOUND INCREASING USE as a salvage therapy in chemo-refractory patients. Herein, the authors describe their experience with SIRT as “stand alone” therapy in a surgically-prohibitive, chemotherapy naive patient with hepatic CRC metastasis. The results suggest that Y-90 SIRT may have potential applications beyond its usual role as a palliative or salvage therapy for unresectable hepatic CRC.

Recommendations for radioembolization of hepatic malignancies using yttrium-90 microsphere brachytherapy: a consensus panel report from the radioembolization brachytherapy oncology consortium

PURPOSE

To standardize the indications, techniques, multimodality treatment approaches, and dosimetry to be used for yttrium-90 (Y90) microsphere hepatic brachytherapy.

METHODS AND MATERIALS

Members of the Radioembolization Brachytherapy Oncology Consortium met as an independent group of experts in interventional radiology, radiation oncology, nuclear medicine, medical oncology, and surgical oncology to identify areas of consensus and controversy and to issue clinical guidelines for Y90 microsphere brachytherapy.

RESULTS

A total of 14 recommendations are made with category 2A consensus. Key findings include the following. Sufficient evidence exists to support the safety and effectiveness of Y90 microsphere therapy. A meticulous angiographic technique is required to prevent complications. Resin microsphere prescribed activity is best estimated by the body surface area method. By virtue of their training, certification, and contribution to Y90 microsphere treatment programs, the disciplines of radiation oncology, nuclear medicine, and interventional radiology are all qualified to use Y90 microspheres. The panel strongly advocates the creation of a treatment registry with uniform reporting criteria. Initiation of clinical trials is essential to further define the safety and role of Y90 microspheres in the context of currently available therapies.

CONCLUSIONS

Yttrium-90 microsphere therapy is a complex procedure that requires multidisciplinary management for safety and success. Practitioners and cooperative groups are encouraged to use these guidelines to formulate their treatment and dose-reporting policies.

Radioembolization with Yttrium-90 microspheres: review of an emerging treatment for liver tumors

Understanding the effect of radiation on tissue, the principles of dosimetry and fractionation have led to the acceptance and adoption of radiation as a standard treatment option for cancer. Delivered in staged and scheduled aliquots, radiation will break nucleic strands and cause cellular death. In general, radiation therapies are delivered using external techniques (external beam and intensity-modulated therapy). One of the limitations of such external techniques is that of nontarget radiation. That is, despite best efforts to collimate and reflect radiation beams to a small target, nontarget radiation and a dose to areas outside the tumor remains a distinct possibility. With the advent of radioembolization using Yttrium-90 microspheres (90Y), the radiation source is delivered optimally through a novel mechanism: directly into the blood vessel providing flow to the tumor. This revolutionary approach capitalizes on the basic principles of tumor hypervascularity, concentrating radiation within that tumor, while at the same time minimizing the risks of nontarget radiation. This review elaborates on this technology.

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 (TheraSphere) treatment of unresectable hepatocellular carcinoma: downstaging to resection, RFA and bridge to transplantation

PURPOSE

To present the clinical data of 35 patients with T3 unresectable hepatocellular carcinoma (HCC) that were treated with (90)Y with the specific intent of downstaging to resection, radiofrequency ablation (RFA) candidate, United Network for Organ Sharing (UNOS) stage T2 or liver transplantation.

MATERIALS AND METHODS

One hundred fifty patients with unresectable HCC were treated with (90)Y microspheres. Of these, 35 patients were UNOS stage T3 at the time of treatment. Patients were followed for clinical toxicities, alterations in model for end-stage-liver disease (MELD) score, tumor response, downstaging to RFA, resection, transplantation, and survival.

RESULTS

Nineteen of 34 patients (56%) were successfully downstaged from T3 to T2 following treatment. 11 of 34 (32%) patients treated were downstaged to target lesions measuring 3.0 cm or less. Twenty-three of 35 (66%) were downstaged to either T2 status, lesion < 3.0 cm (RFA candidate), or resection. Seventeen of 34 (50%) had an objective tumor response by WHO criteria. Eight patients (23%) were successfully downstaged and underwent OLT following treatment. 1, 2, and 3-year survival was 84%, 54%, and 27%, respectively. Median survival by Kaplan-Meier analysis for the entire cohort was 800 days.

CONCLUSION

These data suggest that intra-arterial (90)Y microspheres can be used as a bridge to transplantation, surgical resection, or RFA.

Radioembolization with 90Yttrium microspheres: a state-of-the-art brachytherapy treatment for primary and secondary liver malignancies. Part 1: Technical and methodologic considerations

Microsphere and particle technology represent the next-generation agents that have formed the basis of interventional oncology, an evolving subspecialty of interventional radiology. One of these platforms, yttrium-90 microspheres, is rapidly being adopted in the medical community as an adjunctive therapeutic tool in the management of primary and secondary liver malignancies. Given the complexity of the treatment algorithm of patients who may be candidates for this therapy and the need for clinical guidance, a comprehensive review of the methodologic and technical considerations was undertaken. This experience is based on more than 900 (90)Y infusions performed over a 5-year period.

Hepatic intra-arterial infusion of yttrium-90 microspheres in the treatment of recurrent hepatocellular carcinoma after liver transplantation: A case report

Hepatocellular carcinoma (HCC) recurs with a reported frequency of 12%-18% after liver transplantation. Recurrence is associated with a mortality rate exceeding 75%. Approximately one-third of recurrences develop in the transplanted liver and are therefore amenable to local therapy. A variety of treatment modalities have been reported including resection, transarterial chemo-embolization (TACE), radiofrequency ablation (RFA), ethanol ablation, cryoablation, and external beam irradiation. Goals of treatment are tumor control and the minimization of toxic effect to functional parenchyma. Efficacy of treatment is mitigated by the need for ongoing immunosuppression. Yttrium-90 microspheres have been used as a treatment modality both for primary HCC and for pre-transplant management of HCC with promising results.

Twenty-two months after liver transplantation for hepatitis C cirrhosis complicated by HCC, a 42-year old man developed recurrence of HCC in his transplant allograft. Treatment of multiple right lobe lesions with anatomic resection and adjuvant chemotherapy was unsuccessful. Multifocal recurrence in the remaining liver allograft was treated with hepatic intra-arterial infusion of yttrium-90 microspheres (SIR-Spheres, Sirtex Medical Inc., Lake Forest, IL, USA). Efficacy was demonstrated by tumor necrosis on imaging and a decrease in alpha-fetoprotein (AFP) level. There were no adverse consequences of initial treatment.

Human hepatocyte transplantation: worldwide results

The conception and animal modeling of hepatocyte transplantation along with a partial listing of human hepatocyte infusions over the last 13 years have been detailed in authoritative reviews. However, to adequately best represent the worldwide effort of moving from highly successful clinical solid liver transplants "back to" isolated hepatocyte therapy requires repeating important concepts with explanations of how or why not animal experimental data translate to human experience. This overview summarizes 78 human clinical hepatocyte transplant experiences authenticated by the authors. The human cell infusion experiences are categorized by liver disease treated (metabolic, chronic, and acute liver failure), and these are accompanied by seminal in vitro and in vivo experimental data.

Radioembolization with 90Yttrium Microspheres: A State-of-the-Art Brachytherapy Treatment for Primary and Secondary Liver Malignancies

Yttrium-90 microspheres are increasingly being used as a treatment modality for primary and secondary liver tumors. As these therapies continue to be accepted, it is natural that their application in more complex clinical scenarios will become more common. This article is meant to introduce these controversies and to generate interest and dialogue by the interventional oncology community. This discussion is based on more than 900 (90)Y radioembolization procedures performed over a 5-year period.

Radioembolization using 90Y-resin microspheres for patients with advanced hepatocellular carcinoma

PURPOSE

To investigate the antitumor effect of resin microspheres loaded with 90-yttrium against hepatocellular carcinoma and their safety in the setting of liver cirrhosis.

PATIENTS AND METHODS

Data from 24 consecutive patients with hepatocellular carcinoma (HCC) treated by radioembolization in the period from September 2003 to February 2005 were reviewed. Patients received no further antineoplastic therapy. A comprehensive evaluation was performed to prevent the risk of damage due to microsphere misplacing. Patients were discharged the day after microspheres injection.

RESULTS

Serious liver toxicity observed among cirrhotic patients in a first period was subsequently prevented by modifying the selection criteria and the method for calculating the activity to be administered. Among 21 patients evaluable for response using Response Evaluation Criteria in Solid Tumors (RECIST) criteria, a reduction in size of target lesions was observed in all but 1 patient. When considering only target lesions, disease control rate and response rate were 100% and 23.8%, respectively. However, 43% of patients progressed in the liver in the form of new lesions appearing a median time of 3 months after radioembolization.

CONCLUSION

Our experience in these series of patients indicates that radioembolization using resin microspheres has a significant antitumor effect against HCC and that using stringent selection criteria and conservative models for calculating the radiation activity to be administered, radioembolization can be performed safely even in cirrhotic patients.

New therapies for hepatocellular carcinoma

Hepatocellular carcinoma (HCC), one of the most common cancers worldwide, is often diagnosed at an advanced stage when most potentially curative therapies such as resection, transplantation or percutaneous and transarterial interventions are of limited efficacy. The fact that HCC is resistant to conventional chemotherapy, and is rarely amenable to radiotherapy, leaves this disease with no effective therapeutic options and a very poor prognosis. Therefore, the development of more effective therapeutic tools and strategies is much needed. HCCs are phenotypically and genetically heterogeneous tumors that commonly emerge on a background of chronic liver disease. However, in spite of this heterogeneity recent insights into the biology of HCC suggest that certain signaling pathways and molecular alterations are likely to play essential roles in HCC development by promoting cell growth and survival. The identification of such mechanisms may open new avenues for the prevention and treatment of HCC through the development of targeted therapies. In this review we will describe the new potential therapeutic targets and clinical developments that have emerged from progress in the knowledge of HCC biology, In addition, recent advances in gene therapy and combined cell and gene therapy, together with new radiotherapy techniques and immunotherapy in patients with HCC will be discussed.

Hepatocellular carcinoma

The number of patients who have hepatocellular carcinoma (HCC) is expected to more than double over the next 1 to 2 decades. Patients who have cirrhosis, regardless of cause, are at the highest risk for developing HCC. This article discusses surveillance of these patients for HCC by alpha-fetoprotein and ultrasound, evaluation using imaging, classification of HCC using the Barcelona staging classification, and treatment. Resection, transplantation, and percutaneous ablation are considered curative interventions and are applied to about 30% of all patients who have HCC. Currently, there is no standard therapy for advanced HCC.