Yttrium-90 Radioembolization of the Right Inferior Phrenic Artery in 20 Patients with Hepatocellular Carcinoma

Planning Angiography for 90 Y-Radioembolization Demonstrates a Variety of Unusual Extrahepatic Perfusion Patterns

ABSTRACT

In preparation for 90 Y radioembolization for hepatic malignancies, hepatic angiography is performed with intra-arterial delivery of 99m Tc-macroaggregated albumin (MAA), known as premapping. This initial procedure allows for evaluation of standard/variant hepatic arterial anatomy using MAA as a surrogate marker for the delivery of 90 Y to visualize the likely distribution of 90 Y. Premapping allows for the assessment of at-risk extrahepatic targets and for the quantification of hepatopulmonary shunting. We present cases where MAA scintigraphic images reveal unusual perfusion patterns in hepatic cancers, treated with 90 Y glass microspheres (Therasphere; Boston Scientific, Marlborough, MA).

A morphological study of the inferior phrenic arteries on multidetector computed tomography and angiography

INTRODUCTION

The inferior phrenic artery is a paired artery with a variable origin and course, primarily supplying the diaphragm, but also the suprarenal glands, inferior vena cava, stomach, and oesophagus. The aim of this study is to investigate the origin and course of the inferior phrenic arteries on multidetector computed tomography and angiography.

MATERIALS AND METHODS

The anatomy of the inferior phrenic artery was analysed on 2449 multidetector computed tomography scans. Three-dimensional reconstructions were made of the main variations. Additionally, the course and branching pattern of the inferior phrenic artery were descriptively analysed in a cohort of 28 angiograms.

RESULTS

In 565 (23.1%) cases the inferior phrenic arteries arose as a common trunk and in 1884 (76.9%) cases as individual vessels. The most common origins of a common trunk were the coeliac trunk (n=303; 53.6%) and abdominal aorta (n=255; 45.1%). The most common origins of the right inferior phrenic artery were the coeliac trunk (n=965; 51.2%), abdominal aorta (n=562; 29.8%) and renal arteries (n=214; 11.4%). The most common origins of the left inferior phrenic artery were the coeliac trunk (n=1293; 68.6%) and abdominal aorta (n=403; 21.4%).

CONCLUSION

The inferior phrenic artery has a very variable anatomy. The most common origins of the inferior phrenic artery are the coeliac trunk and its branches, the abdominal aorta, and the renal arteries.

Safety of Radioembolization via the Cystic Artery in Patients with Hepatocellular Carcinoma and Parasitized Arterial Supply

PURPOSE

To evaluate the safety and effectiveness of radioembolization through the cystic artery supplying hepatocellular carcinoma (HCC) adjacent to the gallbladder.

MATERIALS AND METHODS

This retrospective, single-center study included 24 patients who underwent radioembolization via the cystic artery between March 2017 and October 2022. The median tumor size was 8.3 cm (range, 3.4-20.4 cm). Twenty-two (92%) patients had Child-Pugh Class A disease, and 2 (8%) patients had Class B cirrhosis. Technical issues, adverse events, and tumor response were analyzed.

RESULTS

Infusion of radioactive microspheres was performed from the main cystic artery (n = 6), the deep cystic artery (n = 9), and small feeders from the cystic artery (n = 9). The cystic artery supplied the primary index tumor in 21 patients. The median radiation activity delivered via the cystic artery was 0.19 GBq (range, 0.02-0.43 GBq). The median total radiation activity administered was 4.1 GBq (range, 0.9-10.8 GBq). There was no case of symptomatic cholecystitis requiring invasive intervention. One patient experienced abdominal pain during injection of radioactive microspheres via the cystic artery. Eleven (46%) patients received pain medication during or within 2 days of the procedure. Twelve (50%) patients had gallbladder wall thickening on a 1-month follow-up computed tomography scan. Based on follow-up imaging, 23 (96%) patients showed an objective response (complete or partial response) of the tumor supplied by the cystic artery.

CONCLUSION

Radioembolization via the cystic artery may be safe in patients with HCC partially supplied by the cystic artery.

Single-Compartment Dose Prescriptions for Ablative 90Y-Radioembolization Segmentectomy

BACKGROUND

Yttrium-90 (⁹⁰Y) radioembolization is increasingly being utilized with curative intent. While single-compartment doses with respect to the perfused volume for the complete pathologic necrosis (CPN) of tumors have been reported, the actual doses delivered to the tumor and at-risk margins that leads to CPN have hitherto not been estimated. We present an ablative dosimetry model that calculates the dose distribution for tumors and at-risk margins based on numerical mm-scale dose modeling and the available clinical CPN evidence and report on the necessary dose metrics needed to achieve CPN following ⁹⁰Y-radioembolization.

METHODS

Three-dimensional (3D) activity distributions (MBq/voxel) simulating spherical tumors were modeled with a 121 × 121 × 121 mm³ soft tissue volume (1 mm³ voxels). Then, 3D dose distributions (Gy/voxel) were estimated by convolving 3D activity distributions with a ⁹⁰Y 3D dose kernel (Gy/MBq) sized 61 × 61 × 61 mm³ (1 mm³ voxels). Based on the published data on single-compartment segmental doses for the resected liver samples of HCC tumors showing CPN after radiation segmentectomy, the nominal voxel-based mean tumor dose (DmeanCPN), point dose at tumor rim (DrimCPN), and point dose 2 mm beyond the tumor boundary (D2mmCPN), which are necessary to achieve CPN, were calculated. The single-compartment dose prescriptions to required achieve CPN were then analytically modeled for more general cases of tumors with diameters dt = 2, 3, 4, 5, 6, and 7 cm and with tumor-to-normal-liver uptake ratios T:N = 1:1, 2:1, 3:1, 4:1, and 5:1.

RESULTS

The nominal case defined to estimate the doses needed for CPN, based on the previously published clinical data, was a single hyperperfused tumor with a diameter of 2.5 cm and T:N = 3:1, treated with a single-compartment segmental dose of 400 Gy. The voxel-level doses necessary to achieve CPN were 1053 Gy for the mean tumor dose, 860 Gy for the point dose at the tumor boundary, and 561 Gy for the point dose at 2 mm beyond the tumor edge. The single-compartment segmental doses necessary to satisfy the criteria for CPN in terms of the mean tumor dose, point dose at the tumor boundary, and the point dose at 2 mm beyond the tumor edge were tabulated for a range of tumor diameters and tumor-to-normal-liver uptake ratios.

CONCLUSIONS

The analytical functions that describe the relevant dose metrics for CPN and, more importantly, the single-compartment dose prescriptions for the perfused volume needed to achieve CPN are reported for a large range of conditions in terms of tumor diameters (1-7 cm) and T:N uptake ratios (2:1-5:1).

Complications Related to Transarterial Treatment of Hepatocellular Carcinoma: A Comprehensive Review

Currently, various types of transarterial treatments are performed for hepatocellular carcinoma from the early to advanced stages. Its indications and efficacy have been widely investigated. However, procedure-related complications have not been updated in the literature, although new types of transarterial treatments, such as drug-eluting bead transarterial chemoembolization and transarterial radioembolization, are common in daily practice. Herein, a comprehensive literature review was carried out, and complications were organized according to the organs affected and treatment modalities.

Ablative radioembolization of hepatocellular carcinoma with total arterial supply originating from the superior adrenal artery achieved complete pathologic necrosis

Exclusively extrahepatic arterial perfusion to previously untreated, early-stage, hepatocellular carcinoma (HCC) is uncommon. We present a case of right superior adrenal artery completely supplying a subcapsular HCC in a 68-year-old male. The extrahepatic arterial territory targeted excluded structures potentially vulnerable to radiation, which allowed safe ablative Y-90 radioembolization that achieved complete pathological necrosis.

Radioembolization for Hepatocellular Carcinoma: The Effects of Arterioportal Shunts on Nontargeted Liver Hypertrophy

PURPOSE

To determine whether arterioportal shunting to the contralateral lobe attenuates the liver function and the hypertrophy of the nontargeted liver after radioembolization in patients with hepatocellular carcinoma (HCC) MATERIALS AND METHODS: This retrospective study included 46 patients who received radioembolization for HCC contained within the right lobe between 2012 and 2020. The patients were divided into the following groups based on the presence and extent of arterioportal shunt : patients with retrograde arterioportal shunting to the left lobe (contralateral group) and patients with arterioportal shunt limited to the right lobe or no arterioportal shunt (control group). Safety profiles including adverse events, tumor response and overall survival were compared. With the volume of left lateral segment used as a surrogate marker for nontarget liver, degree of hypertrophy was compared between two groups at 3 and 6 months.

RESULTS

Liver function significantly deteriorated in contralateral group in a month (p=<0.05). Tumor response and overall survival did not significantly differ between two groups. Degree of hypertrophy was significantly higher in the control group compared with the contralateral group at 3 months [10.6% vs 3.5% (p = 0.008)] and at 6 months [20.7% vs 2.4% (p < 0.001)].

CONCLUSION

In patients with arterioportal shunting to the contralateral lobe, hypertrophy of the nontarget liver may not occur and the liver function may be worsened.

Yttrium-90 Radioembolization Is Associated with Better Clinical Outcomes in Patients with Hepatocellular Carcinoma Compared with Conventional Chemoembolization: A Propensity Score-Matched Study

Background

Both trans-arterial radioembolization (TARE) and conventional trans-arterial chemoembolization (TACE) can effectively control hepatocellular carcinoma (HCC) in patients who are not suitable for curative resection. This study compared the effectiveness of TARE and conventional TACE as the initial trans-arterial treatment for hepatocellular carcinoma (HCC) assessed by tumor response and clinical outcomes.

Material and Methods

Data were retrospectively analyzed the propensity score-matched cohort for overall survival (OS), progression-free survival (PFS), and intrahepatic PFS in patients who have received TARE or TACE as the first HCC treatment from March 2012 to December 2017.

Results

A total of 138 patients initially treated with TARE (n = 54) or TACE (n = 84) was included in this study. Of 138 patients, median age was 59 years and the mean follow-up period was 27.6 months. TARE showed better OS (hazard ratio [HR] = 0.54, 95% confidence interval [CI] = 0.31–0.92, log-rank P = 0.02), better PFS (HR = 0.51, 95% CI = 0.36–0.97, log-rank P = 0.04), and better intrahepatic PFS (HR = 0.51, 95% CI = 0.30–0.88, log-rank P = 0.01) compared with TACE. TARE was an independent prognostic factor for OS (adjusted HR [aHR] = 0.52, 95% CI = 0.30–0.90, P = 0.02), PFS (aHR = 0.57, 95% CI = 0.35–0.94, P = 0.03), and intrahepatic PFS (aHR = 0.49, 95% CI = 0.28–0.84, P = 0.01).

Conclusion

TARE as initial trans-arterial treatment is associated with better clinical outcomes such as longer OS compared with TACE in patients with HCC.

Lung Shunt Reduction for Yttrium-90 Radioembolization: Chemoembolization Versus Radioembolization

AIM

To evaluate the efficacy of chemoembolization versus radioembolization in reducing lung shunt fraction (LSF) in patients with hepatocellular carcinoma (HCC).

PATIENTS AND METHODS

In this retrospective study, from March 2012 to January 2021, 457 patients with HCC underwent planning angiography and ^99mTc-macroaggregated albumin imaging for possible yttrium-90 radioembolization. Ten patients underwent radioembolization, and seven patients underwent conventional chemoembolization for LSF reduction, and a second ^99mTc-macroaggregated albumin imaging was obtained approximately 1 month later. LSF under both procedures was compared with the Mann-Whitney U-test and the Wilcoxon signed-rank test.

RESULTS

In the radioembolization group, the mean first and second LSF were 13.0±6.9% and 20.9±9.6%, respectively (p=0.059); after radioembolization, LSF was lower in three patients but higher in seven patients. In the chemoembolization group, the mean first and second LSF were 26.1±17.3% and 8.7±5.5%, respectively (p=0.018); after chemoembolization, LSF was reduced in all seven patients.

CONCLUSION

Chemoembolization appears to be more effective in reducing LSF within 1 month compared with radioembolization.

Combination of 1st and 2nd Week Dosing of Glass Yttrium-90 Microspheres for Superselective Radioembolization

BACKGROUND/AIM

The aim of this study was to address the feasibility of combination of 1^st and 2^nd week dosing of glass microspheres in the setting of selective radioembolization for large hepatocellular carcinoma (HCC).

PATIENTS AND METHODS

Yttrium-90 radioembolization was performed in 53 patients with single nodular hepatocellular carcinomas larger than 5 cm. A total of 32 patients underwent radioembolization with glass microspheres from a single calibration date (single-dosing group), and 21 patients were treated with a combination of 1^st and 2^nd week dosing of glass microspheres (combined-dosing group). In the combined-dosing group, the lobar hepatic arteries and subsidiary tumor-feeding arteries were commonly treated with 1^st and 2^nd week dosing of glass microspheres, respectively.

RESULTS

The combined-dosing group tended to have a lower frequency of pain requiring analgesics without statistical significance (p=0.085). The objective response rate at 3 months in single-dosing group and combined-dosing group was 46.9% (15 out of 32) and 66.7% (14 out of 21), respectively.

CONCLUSION

The combined 1^st and 2^nd week dosing of glass microspheres demonstrated an acceptable toxicity and tumor response when both a lobar hepatic artery and a small tumor-feeding artery need to be treated in one session.

Benign Biliary Stricture after Yttrium-90 Radioembolization for Hepatocellular Carcinoma

PURPOSE

To determine the frequency and possible causative factors of benign biliary stricture after radioembolization in patients with hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

This retrospective study comprised 232 patients with HCC who underwent yttrium-90 radioembolization between October 2015 and September 2019. Benign biliary stricture was defined as biliary ductal dilatation of segmental or lobar biliary ducts on follow-up images. Clinical and radiologic characteristics were compared using χ² test or independent t test.

RESULTS

Mean target perfused tissue dose was 224.6 Gy ± 106.8 (median, 205.7 Gy; range, 47.0-694.7 Gy). Of 232 patients, 15 (6.5%) had benign biliary stricture, which was detected from 3 weeks to 10.3 months (mean, 3.9 months; median, 3.2 months). Whereas 5 patients did not have any symptoms or signs associated with benign biliary stricture, 10 patients had cholangitis and/or laboratory abnormality requiring biliary drainage procedures and intravenous antibiotic therapy. Selective radioembolization through a caudate artery was performed in 55 (23.7%) patients. The incidence of benign biliary stricture was 16.4% (9/55) and 3.4% (6/177) in patients with and without selective radioembolization through a caudate artery, respectively (P = .002).

CONCLUSIONS

Benign biliary stricture following yttrium-90 radioembolization may be common among patients receiving selective treatment via a caudate artery.

Bridging and downstaging role of trans-arterial radio-embolization for expected small remnant volume before liver resection for hepatocellular carcinoma

Backgrounds/Aims

To evaluate our initial experience of bridging role of trans-arterial radio-embolization (TARE) before major hepatectomy for hepatocellular carcinoma (HCC) in risky patients with small expected remnant liver volume (ERLV).

Methods

We reviewed the data of patients with HCC who underwent major hepatectomy after TARE during the period between March and December 2017. Patients included had uni-lobar large HCC (>5 cm) requiring major hepatectomy with small ERLV.

Results

Five patients were included in our study. All patients were Child Pugh class A. A single session of TARE was applied in all patients. None developed any adverse events related to irradiation. The mean tumor size at baseline was 8.4 cm and 6.1 cm after TARE (p=0.077). The mean % of tumor shrinkage was 24.5%. ERLV improved from 354.6 ml at baseline to 500.8 ml after TARE (p=0.012). ERLV percentage improved from 27.2% at baseline to 38.1% after TARE (p=0.004). The mean % of ERLV was 39.5%. The mean interval time between TARE and resection was 99.6 days. Four patients (80%) underwent right hemi-hepatectomy and one patient (20%) underwent extended right hemi-hepatectomy. The mean operation time was 151 minutes, and mean blood loss was 56 ml. The mean hospital stay was 13.8 days, and one patient (20%) developed postoperative morbidity. After a mean follow-up of 15 months, all patients were alive with no recurrence.

Conclusions

Yttrium-90 TARE can play a bridging role before major hepatectomy for borderline resectable HCC in risky patients with small ERLV.

Feasibility of Boosted Radioembolization for Hepatocellular Carcinoma Larger than 5 cm

PURPOSE

To address the feasibility of yttrium-90 (⁹⁰Y) glass microspheres administered at a boosted dose in large hepatocellular carcinomas (HCCs).

MATERIALS AND METHODS

From July 2016 to August 2017, 20 patients who underwent ⁹⁰Y radioembolization for treatment-naïve HCC met the following inclusion criteria: (i) nodular tumor, (ii) tumor size > 5 cm, (iii) Barcelona Clinic Liver Cancer stage A/B disease, (iv) target perfused tissue dose > 150 Gy, and (v) all tumors treated in 1 session of radioembolization. Follow-up radiologic findings and clinical outcomes were retrospectively reviewed until May 2018. Tumor response was determined per modified Response Evaluation Criteria In Solid Tumors.

RESULTS

Mean total radiation activity infused was 4.96 GBq ± 1.82 (median, 4.88 GBq; range, 1.63-9.15 GBq). Mean target perfused tissue dose was 263.5 Gy ± 95.2 (median, 241.6 Gy; range, 156.2-550.6 Gy). The mean number of vials used per treatment was 4.15 ± 1.4 (median, 4; range, 2-7). Complete response rates were 25% at 1 month and 60% at 3 months. Complete response of the primary index tumor was achieved in 16 patients (80%) based on best tumor response. Local progression-free survival and progression-free survival rates were 94.1% and 85.0% at 6 mo and 94.1% and 74.7% at 1 year, respectively. Four patients (20%) had symptomatic (n = 3) or asymptomatic (n = 1) benign biliary strictures.

CONCLUSIONS

Radioembolization with a boosted dose in patients with large HCCs may show favorable tumor response, but with considerable biliary complications.