Impact of Prior Hepatectomy on the Safety and Efficacy of Radioembolization With Yttrium-90 Microspheres for Patients With Unresectable Liver Tumors

Cholecystitis induced by Yttrium-90 radioembolization of advanced liver tumors: prospective evaluation of a management algorithm in 197 consecutive patients

BACKGROUND

Cholecystitis is a rare but dolorous complication after Y90-radioembolization of liver malignancies.

PURPOSE

To decide the occlusion of the cystic artery (CA) to prevent cholecystitis after Y90 radioembolization using an algorithm.

MATERIAL AND METHODS

In 130 patients, the gallbladder was at risk of embolization as the right liver lobe was targeted. Precautionary measures (e.g. coil occlusion of the cystic artery) were decided by enhancement of the gallbladder in pre-treatment Tc99m-MAA SPECT/CT and performed directly before Y90 radioembolization. In non-enhancing cases, the CA was left open. The outcome was determined by clinical symptoms of acute or chronic cholecystitis as well as imaging and laboratory parameters. Findings were additionally classified according to the Tokyo Guidelines of acute cholecystitis.

RESULTS

Only 16 patients demonstrated enhancement of the gallbladder in Tc99m-MAA SPECT/CT. Including additional indications from angiographic findings, prophylactic measures were scheduled in 22 patients (standard of care). Thus, 121 patients were at risk of non-target embolization to the gallbladder during Y90 microsphere administration (investigative arm). Four cases (3.0%) of cholecystitis occurred by clinical presentation: two patients with onset of acute symptoms within 48 h after Y90 radioembolization ("embolic cholecystitis") and two patients with late onset of symptoms ("radiogenic cholecystitis"). The incidence of cholecystitis was not significantly more frequent without indication of precautionary measures (investigative cohort 2.9% vs. standard of care 4.7%; P = 0.53).

CONCLUSION

The overall incidence of cholecystitis after Y90 radioembolization is low. Determination of cystic artery intervention using Tc99m-MAA SPECT/CT successfully balances the incidence of symptomatic cholecystitis with unnecessary vessel occlusion.

Chronic Hepatotoxicity in Patients with Metastatic Neuroendocrine Tumor: Transarterial Chemoembolization versus Transarterial Radioembolization

PURPOSE

To compare the manifestations of chronic liver injury following transarterial chemoembolization with those of transarterial radioembolization (TARE) in patients with neuroendocrine tumor (NET).

MATERIALS AND METHODS

This study consisted of an Institutional Review Board-approved single-institution retrospective analysis of NET patients who received transarterial chemoembolization from 2006 to 2016 and TARE from 2005 to 2014 and survived at least 1 year from the initial treatment. Patients receiving only transarterial chemoembolization (n = 63) or TARE (n = 28) were evaluated for the presence or absence of durable hepatic toxicities occurring at least 6 months after initial treatment. The definitions and grades of liver injury were adapted from Common Terminology Criteria for Adverse Events version 4.0 and were characterized by the presence of laboratory or clinical toxicities of Grade 3 or above.

RESULTS

Chronic hepatic toxicity occurred in 14 of 63 transarterial chemoembolization patients (22%) with a total of 26 Grade 3-4 events, in whom elevation of bilirubin was the most common toxicity, compared to 8 of 28 TARE patients (29%) with a total of 16 Grade 3-4 and 2 Grade 5 events, in whom ascites were the most frequent toxicity. There were more laboratory toxicities in the transarterial chemoembolization group (65% vs 38%, P = .11) and fewer Grade 4-5 injuries (6% vs 27% of patients, P = .06). There was also a significantly higher number of patients who experienced intrahepatic progression of disease in the transarterial chemoembolization cohort than in the TARE patients (75% vs 43%, respectively; P = .005).

CONCLUSIONS

Delayed hepatotoxicity from transarterial chemoembolization and TARE occurred in 22% and 29% of patients, respectively, from 6 months to several years following treatment. Transarterial chemoembolization-related toxicities on average were less severe and manifested primarily as laboratory derangements, compared to TARE toxicities which consisted of clinical hepatic decompensation.

Molecular Imaging and Therapy of Liver Tumors

Liver cancer is one of the top leading causes of mortality worldwide. Conventional imaging using contrast enhanced CT and MRI are currently the mainstay of oncologic imaging of the liver for the diagnosis and management of cancer. In the past two decades, especially since the advent of hybrid imaging in the form of PET/CT and SPECT/CT, molecular imaging has been increasingly utilized for oncologic imaging and the variety of radionuclide probes for imaging liver cancers have been expanding. Beyond the usual workhorse of FDG as an oncologic tracer, there is a growing body of evidence showing that radiolabeled choline tracers, C-11 acetate and other new novel tracers may have increasing roles to play for the imaging of liver tumors. On the therapy front, there have also been advances in recent times in terms of targeted therapies for both primary and secondary liver malignancies, particularly with transarterial radioembolization. The concept of theranostics can be applied to transarterial radioembolization by utilizing a pretreatment planning scan, such as Tc-99m macroaggregated albumin scintigraphy, coupled with post treatment imaging. Radiation dose planning by personalized dosimetric calculations to the liver tumors is also being advocated. This article explores the general trends in the field of nuclear medicine for the imaging and treatment of liver cancer above and beyond routine diagnosis and management.

Incidence of Radioembolization-Induced Liver Disease and Liver Toxicity Following Repeat 90Y-Radioembolization: Outcomes at a Large Tertiary Care Center

PURPOSE

The complication profile following repeat Y-radioembolization (RE) is not well understood, and repeat RE is sometimes avoided because of concerns for RE-induced liver disease (REILD) and liver toxicity. The purpose of this study was to examine the incidence of REILD and liver toxicity following repeat Y-RE and to identify potential risk factors.

METHODS

A retrospective analysis of patients undergoing repeat RE to the same hepatic lobe between 2013 and 2018 was performed. Baseline factors were evaluated as predictors of liver toxicity, mortality, and REILD, which was defined as the presence symptomatic ascites or jaundice in the absence of biliary obstruction within 8 weeks following RE. Post-RE complications were graded according to the Common Terminology Criteria for Adverse Events version 5.

RESULTS

A total of 39 patients underwent repeat RE with 14 (35.9%) experiencing Common Terminology Criteria for Adverse Events toxicity of grade 2 or greater, 3 (10.3%) grade 3, and no grade 4 or greater. A Model for End Stage Liver Disease score of 8 or greater was associated with grade 2 toxicity or greater (26.7% vs 75%; P = 0.013). Only 3 patients (7.7%) experienced REILD due to symptomatic ascites without jaundice. Greater than 2 REs were associated with a greater rate of 6-month mortality (12% vs 58.3%, P = 0.003), 12-month mortality (28% vs 75%, P = 0.007), and REILD (0% vs 21.4%, P = 0.016). Age, sex, microsphere type, cirrhosis, Child-Pugh, and Eastern Cooperative Oncology Group status were not significantly associated with complications, REILD, or survival.

CONCLUSIONS

Repeat Y-RE appears to be well tolerated with a low rate of high-grade adverse events and REILD.

Yttrium-90 Radioembolization After Local Hepatic Therapy: How Prior Treatments Impact Patient Selection, Dosing, and Toxicity

Numerous local treatment strategies now exist for patients with primary and metastatic liver tumors. Increasingly, patients who cannot be adequately treated with a single form of focal therapy, go on to receive a variety of sequential treatments. However, the impact of each prior therapy on subsequent treatments and the cumulative toxicity of these therapies remains uncertain. Yttrium-90 radioembolization is becoming an increasingly common treatment for patients with hepatic malignancies. Though the baseline toxicity of radioembolization is low, greater care must be taken when treating patients who have undergone prior hepatic treatments. While this population can be treated safely, additional measures should be taken to ensure that patients are carefully screened and all effort is made to minimize liver toxicity.

Recommendations for radioembolisation after liver surgery using yttrium-90 resin microspheres based on a survey of an international expert panel

INTRODUCTION

Guidelines on how to adjust activity in patients with a history of liver surgery who are undergoing yttrium-90 radioembolisation (90Y-RE) are lacking. The aim was to study the variability in activity prescription in these patients, between centres with extensive experience using resin microspheres 90Y-RE, and to draw recommendations on activity prescription based on an expert consensus.

METHODS

The variability in activity prescription between centres was investigated by a survey of international experts in the field of 90Y-RE. Six representative post-surgical patients (i.e. comparable activity prescription, different outcome) were selected. Information on patients' disease characteristics and data needed for activity calculation was presented to the expert panel. Reported was the used method for activity prescription and whether, how and why activity reduction was found indicated.

RESULTS

Ten experts took part in the survey. Recommendations on activity reduction were highly variable between the expert panel. The median intra-patient range was 44 Gy (range 18-55 Gy). Reductions in prescribed activity were recommended in 68% of the cases. In consensus, a maximum DTarget of 50 Gy was recommended.

CONCLUSION

With a current lack of guidelines, large variability in activity prescription in post-surgical patients undergoing 90Y-RE exists. In consensus, DTarget ≤50 Gy is recommended.

KEY POINTS

• BSA method does not account for a decreased remnant liver volume after surgery. • In post-surgical patients, a volume-based activity determination method is recommended. • In post-surgical patients, a mean D Target of ≤ 50Gy should be aimed for.

Radioembolisation of hepatocellular carcinoma: a primer

Transarterial radioembolisation (TARE) has gained increasing acceptance as an additional/alternative locoregional treatment option for hepatocellular carcinoma, and colorectal hepatic metastases that present beyond potentially curative options. This is a catheter-based transarterial selective internal brachytherapy that involves injection of radioactive microspheres (usually Y-90) that are delivered selectively to the liver tumours. Owing to the combined radioactive and microembolic effect, the findings at follow-up imaging are significantly different from that seen with other transarterial treatment options. Considering increasing confidence among clinicians, refinement in techniques and increasing number of ongoing trials, TARE is expected to gain further acceptance and become an important tool in the armamentarium for the treatment of liver malignancies. So it is imperative that all radiologists involved in the management of liver malignancies are well versed with TARE to facilitate appropriate discussion at multidisciplinary meetings to direct further management. In this article, we provide a comprehensive review on various aspects of radioembolisation with Y-90 for hepatocellular carcinoma including the patient selection, treatment planning, radiation dosimetry and treatment, side effects, follow-up imaging and future direction.

Radioembolization-induced liver disease: a systematic review

Radioembolization (RE) is a relatively novel treatment modality for primary and secondary hepatic malignancies. Microspheres embedded with a β-emitting radioisotope are injected into the hepatic artery, resulting in microsphere deposition in the tumor arterioles and normal portal triads. Microsphere deposition in nontumorous parenchyma can result in radiation-induced liver injury, with lethal RE-induced liver disease (REILD) at the outer end of the spectrum. The primary aim of this study was to evaluate RE-related hepatotoxicity and present an overview of the currently applied definitions and clinically relevant characteristics of REILD. A systematic literature search on REILD was performed. Studies after the introduction of the term REILD (2008) were screened for definitions of REILD. Hepatotoxicity and applied definitions of REILD were compared. Liver biochemistry test abnormalities occur in up to 100% of patients after RE, mostly self-limiting. The incidence of symptomatic REILD varied between 0 and 31%, although in most reports, the incidence was 0-8%, with a lethal outcome in 0-5%. With the exception of bilirubin, the presentation of hepatotoxicity and REILD was similar for cirrhotic and noncirrhotic patients. No uniform definition of REILD was established in the current literature. Here, we propose a unifying definition and grading system for REILD. RE-related hepatotoxicity is a common phenomenon; symptomatic REILD, however, is rare. Currently, reporting of REILD is highly variable, precluding reliable comparison between studies, identification of risk factors, and treatment developments.

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.

Yttrium-90 microspheres: a review of its emerging clinical indications

BACKGROUND

Many patients with liver malignancies are not candidates for resection, and systemic therapies are often not effective. Radioembolization (RE) is an alternative treatment for this group of patients. The safety and efficacy of RE with yttrium 90 (Y90) in patients with hepatocellular carcinoma (HCC) or metastatic colon cancer to the liver have been proven in several studies. However, fewer studies have focussed on the safety and efficacy of RE with Y90 in other extrahepatic primary and secondary liver cancers. The effect on outcomes of concomitant use of Y90 with a systemic therapy is still currently under investigation.

SUMMARY

A review of the published data on the use of RE as stand-alone, concomitant or sequential with other treatment modalities in HCC and other primary and secondary liver cancer is reported here.

KEY MESSAGE

RE for the treatment of HCC and other extrahepatic, primary and secondary liver cancer has reasonable efficacy and acceptable toxicities. Definitive studies to establish the role of RE in the treatment of such malignancies are warranted.

Liver resection for metastatic disease after y90 radioembolization: a case series with long-term follow-up

INTRODUCTION

There are only few reports of liver resections for metastatic disease in patients previously treated with Y-90 radioembolization (RE), and long-term outcome data are sparse. We reviewed our center's experience in patients undergoing hepatectomy after hepatic RE.

METHODS

A retrospective chart review of patients undergoing RE from 2004 to 2011 was performed. Demographic, clinicopathologic, operative, and long-term outcomes variables were collected. Independent pathologic review of tumor necrosis and normal liver tissue grading of fibrosis and inflammation after resection was performed. Data are expressed as medians and ranges.

RESULTS

RE was delivered to 106 patients with primary and metastatic disease of the liver, of whom 9 patients (6 males, 3 females, median age 54 (47-76) years) with metastatic disease ultimately underwent resection. RE was previously administered to the right liver in five, the left liver in one, and to the whole liver in three. Two patients had a second RE performed before resection. Six of the nine patients had previously received several infusions of cytotoxic therapy. The operations occurred at a median of 115 (56-245) days after RE and included right lobectomy (n = 5), left lobectomy (n = 1), left-lateral sectionectomy (n = 1), and bilobar wedge resections (n = 2). Extrahepatic sites were resected in three patients. Median blood loss was 900 (range 250-3600) ml. Grade 3 or higher complications occurred in seven cases (78 %). Follow-up was complete all nine patients. Three patients (33 %) died within 30 days of resection. All those surviving the operative period had disease recurrence (time to recurrence: 202 [range 54-315] days), and all have since died (overall survival: 584 [range 127-1230] days). Review of resected specimens demonstrated median tumor necrosis of 70 % (range 20-90 %). In nontumor-bearing liver, fibrosis grade (0-4) and inflammation score (0-4) was 2 or less in all specimens.

CONCLUSIONS

In this small cohort of highly selected and heavily pretreated patients, long-term survival in patients undergoing resection after RE appears possible, but the operations may carry substantial risks-highlighting the importance of careful patient selection for these resections. The etiology of morbidity and mortality is likely multifactorial and additional reports that include long-term outcomes will be necessary to identify more clearly the impact of RE on postoperative complications and death.

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.

Side effects of yttrium-90 radioembolization

Limited therapeutic options are available for hepatic malignancies. Image guided targeted therapies have established their role in management of primary and secondary hepatic malignancies. Radioembolization with yttrium-90 ((90)Y) microspheres is safe and efficacious for treatment of hepatic malignancies. The tumoricidal effect of radioembolization is predominantly due to radioactivity and not ischemia. This article will present a comprehensive review of the side effects that have been associated with radioembolization using (90)Y microspheres. Some of the described side effects are associated with all transarterial procedures. Side effects specific to radioembolization will also be discussed in detail. Methods to decrease the incidence of these potential side effects will also be discussed.