Benign Biliary Stricture after Yttrium-90 Radioembolization for Hepatocellular Carcinoma

PurposeTo determine the frequency and possible causative factors of benign biliary stricture after radioembolization in patients with hepatocellular carcinoma (HCC).Materials and MethodsThis 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.ResultsMean 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).ConclusionsBenign biliary stricture following yttrium-90 radioembolization may be common among patients receiving selective treatment via a caudate artery.     

Induction of Contralateral Hepatic Hypertrophy by Unilobar Yttrium-90 Transarterial Radioembolization versus Portal Vein Embolization: An Animal Study

PurposeTo compare hepatic hypertrophy in the contralateral lobe achieved by unilobar transarterial radioembolization (TARE) versus portal vein embolization (PVE) in a swine model.MethodsAfter an escalation study to determine the optimum dose to achieve hypertrophy after unilobar TARE in 4 animals, 16 pigs were treated by TARE (yttrium-90 resin microspheres) or PVE (lipiodol/n-butyl cyanoacrylate). Liver volume was calculated based on CT before treatment and during 6 months of follow-up. Independent t-test (P < .05) was used to compare hypertrophy. The relationship between hypertrophy after TARE and absorbed dose was calculated using the Pearson correlation.ResultsAt 2 and 4 weeks after treatment, a significantly higher degree of future liver remnant hypertrophy was observed in the PVE group versus the TARE group, with a median volume gain of 31% (interquartile range [IQR]: 16%–66%) for PVE versus 23% (IQR: 6%–36%) for TARE after 2 weeks and 51% (IQR: 47%–69%) for PVE versus 29% (IQR: 20%–50%) for TARE after 4 weeks. After 3 and 6 months, hypertrophy converged without a statistically significant difference, with a volume gain of 103% (IQR: 86%–119%) for PVE versus 82% (IQR: 70%–96%) for TARE after 3 months and 115% (IQR: 70%–46%) for PVE versus 86% (IQR: 58%–111%) for TARE after 6 months. A strong correlation was observed between radiation dose (median 162 Gy, IQR: 139–175) and hypertrophy.ConclusionsPVE resulted in rapid hypertrophy within 1 month of the procedure, followed by a plateau, whereas TARE resulted in comparable hypertrophy by 3–6 months. TARE-induced hypertrophy correlated with radiation absorbed dose.     

Same-Day Repeat Hepatopulmonary Shunt Measurement during Planning Angiography for Hepatic Radioembolization

This report describes a technique for measuring lung shunt fraction (LSF) twice in a single session during planning arteriography for radioembolization using low and standard dose technetium-99m macroaggregated albumin (^99mTc-MAA). A patient with a 16.0 cm hepatocellular carcinoma and LSF of 70% was treated with lenvatinib for 4 weeks. Planning arteriography with administration of 0.5 millicuries of ^99mTc-MAA was then performed. Arterial access was maintained while the LSF was calculated, which was persistently elevated at 54%. Embolization of arteriovenous shunts was performed during the same session and 5.0 millicuries of ^99mTc-MAA were administered. The repeat LSF was 29%. Successful radioembolization was subsequently performed.     

Yttrium-90 Radiation Segmentectomy of Hepatocellular Carcinoma: A Comparative Study of the Effectiveness,Safety, and Dosimetry of Glass-Based versus Resin-Based Microspheres

PurposeTo evaluate the differences in safety, effectiveness, and dosimetry between glass-based and resin-based ablative yttrium-90 (⁹⁰Y) transarterial radioembolization (TARE) of hepatocellular carcinoma (HCC).Materials and MethodsUsing the modified Response Evaluation Criteria in Solid Tumors and Common Terminology Criteria for Adverse Events, both tumor response and adverse events (AEs) were assessed at 3 months after ⁹⁰Y-TARE. Post procedure ⁹⁰Y-bremsstrahlung single-photon emission computed tomography/computed tomography voxel-based dosimetry analysis was used to create tumor dose (TD) and normal tissue dose (NTD) volume histograms, and to calculate tumor particle loading and specific activity. The TD and NTD receiver operating characteristic curves evaluated the dose threshold able to predict objective (partial or complete) and complete tumor responses in addition to any-grade and grade ≥3 AE incidences. The chi-square test and Student t-test were used to assess variable differences where appropriate.ResultsBetween 2019 and 2020, 81 patients with HCC (20 in the resin-based cohort and 61 in the glass-based cohort) underwent ablative ⁹⁰Y-TARE. The resin-based cohort had more males (89% vs 65%, P = .03), lower tumor-to-normal ratio (1.81 ± 0.39 vs 2.22 ± 0.94, P = .03), higher tumor particle loading (40,172 particles/mL ± 28,039 vs 17,081 particles/mL ± 12,555, P = .0001), lower specific activity (158 Bq/particle ± 3 vs 1,058 Bq/particle ± 331, P = .001), and lower mean TD (308 Gy ± 210 vs 794 Gy ± 523, P = .0002) than the glass-based cohort. No significant differences in baseline characteristics or posttreatment AEs were noted. The overall objective and complete response rates were 85% (95% resin-based vs 82% glass-based; P = .1) and 65% (95% resin-based vs 56% glass-based; P = .003), respectively. The mean TD thresholds able to predict the objective and complete responses were 176 Gy and 247 Gy for resin-based radioembolization and 290 Gy and 481 Gy for glass-based radioembolization, respectively. A maximum NTD of 999 Gy predicted any-grade AEs in glass-based ablative ⁹⁰Y-TARE.ConclusionsCompared with glass-based ablative ⁹⁰Y-TARE, resin-based ablative ⁹⁰Y-TARE can offer comparable safety and effectiveness profiles for patients with HCC. The impact of the significantly different tumor particle loading, particle specific activities, and delivered TDs on tumor response outcomes merits further investigation.     

Survival and Toxicities after Yttrium-90 Transarterial Radioembolization of Cholangiocarcinoma in the RESiN Registry

PurposeTo report outcomes in patients with intrahepatic cholangiocarcinoma treated with yttrium-90 resin microspheres (transarterial radioembolization [TARE]) from a multicenter, prospective observational registry.Materials and MethodsNinety-five patients (median age, 67 years [interquartile range {IQR}, 59–74]; 50 men) were treated in 27 centers between July 2015 and August 2020. Baseline demographic characteristics included imaging findings, performance status, and previous systemic or locoregional treatments. Dosimetry method was tracked. Overall survival (OS) and progression-free survival were calculated using the Kaplan-Meier method. The best imaging response was calculated using the Response Evaluation Criteria in Solid Tumors v1.1. Grade ≥3 toxicities were assessed using Common Terminology Criteria for Adverse Events v5. Cox regression analysis was performed.ResultsFifty-two of 86 (60%) patients had multifocal tumors, and 24/89 (27%) had extrahepatic tumors. The median index tumor diameter was 7.0 cm (IQR, 4.9–10 cm). The activity calculation method was reported in 59/95 (62%) patients, with body surface area being the most frequently used method (45/59, 76%). Median OS for the cohort was 14 months (95% confidence interval, 12–22). OS at 3, 6, 12, and 24 months was 94%, 80%, 63%, and 34%, respectively. Median OS was longer in patients without cirrhosis (19.1 vs 12.2 months, P = .05). Cirrhosis, previous chemotherapy (OS, 19.1 vs 10.6 months for treatment-naïve; P = .07), and imaging response at 6 months (OS, 16.4 vs 9.5 months for no response; P = .06) underwent regression analysis. Imaging response predicted OS at regression (hazard ratio, 0.39; P = .008). Grade 3–4 bilirubin toxicities were noted in 5 of 72 (7%) patients. Grade 3 albumin toxicity was noted in 1 of 72 (1.4%) patients.ConclusionsObjective response at 6 months predicted longer OS after TARE for intrahepatic cholangiocarcinoma. The incidence of liver function toxicity was <10%.     

Radioembolization with Yttrium-90 Glass Microspheres as a First-Line Treatment for Unresectable Intrahepatic Cholangiocarcinoma—A Prospective Feasibility Study

PurposeTo evaluate the safety and effectiveness of yttrium-90 (⁹⁰Y) radioembolization as first-line treatment for unresectable intrahepatic cholangiocarcinoma (ICC).Materials and MethodsThis prospective study enrolled patients who had never received chemotherapy, liver embolization, and radiation therapy. The tumors were solitary in 16 patients, multiple in 8 patients, unilobar in 14 patients, and bilobar in 10 patients. Patients underwent transarterial radioembolization with ⁹⁰Y-labeled glass microspheres. The primary end point was hepatic progression-free survival (HPFS). Secondary end points were overall survival (OS), tumor response, and toxicity.ResultsTwenty-four patients (age, 72.3 years ± 9.3; 12 women) were included in the study. The median delivered radiation dose was 135.5 Gy (interquartile range, 77.6 Gy). The median HPFS was 5.5 months (95% CI, 3.9–7.0 months). Analysis failed to identify any prognostic factor associated with HPFS. Imaging response at 3 months showed 56% disease control, and the best radiographic response was 71% disease control. The median OS from the radioembolization treatment was 19.4 months (95% CI, 5.0–33.7). Patients with solitary ICC had significantly longer median OS than patients with multifocal ICC: 25.9 months (95% CI, 20.8–31.0 months) versus 10.7 months (95% CI, 8.0–13.4 months) (P = .02). Patients with progression on the 3-month imaging follow-up had significantly shorter median OS than patients who had stable disease at 3 months: 10.7 months (95% CI, 0.7–20.7 months) versus 37.3 months (95% CI, 16.5–58.1 months) (P = .003). Two (8%) Grade 3 toxicities were reported.ConclusionsFirst-line treatment of ICC with radioembolization showed promising OS and minimal toxicity, especially in patients with solitary tumor. Radioembolization may be considered as a first-line treatment option for unresectable ICC.     

Predictors of Survival after Yttrium-90 Radioembolization of Chemotherapy-Refractory Hepatic Metastases from Breast Cancer

PurposeTo determine predictors of survival after transarterial radioembolization of hepatic metastases from breast cancer.Materials and MethodsTwenty-four patients with chemotherapy-refractory hepatic metastases from breast cancer who underwent radioembolization from 2013 to 2018 were evaluated based on various demographic and clinical factors before and after treatment. Overall survival (OS) was estimated by Kaplan–Meier method. Log-rank analysis was performed to determine predictors of prolonged OS from the time of first radioembolization and first hepatic metastasis diagnosis.ResultsMedian OS times were 35.4 and 48.6 months from first radioembolization and time of hepatic metastasis diagnosis, respectively. Radioembolization within 6 months of hepatic metastasis diagnosis was a positive predictor of survival from first radioembolization, with median OS of 38.9 months vs 22.1 months for others (P = .033). Estrogen receptor (ER)–positive status predicted prolonged survival (38.6 months for ER⁺ vs 5.4 months for ER⁻; P = .005). The presence of abdominal pain predicted poor median OS: 12.8 months vs 38.6 months for others (P < .001). The presence of ascites was also a negative predictor of OS (1.7 months vs 35.4 months for others; P = .037), as was treatment-related grade ≥ 2 toxicity at 3 months (5.4 months vs 38.6 months for others; P = .017).ConclusionsIn patients with metastatic breast cancer, radioembolization within 6 months of hepatic metastasis diagnosis and ER⁺ status appear to be positive predictors of prolonged survival. Conversely, baseline abdominal pain, baseline ascites, and treatment-related grade ≥ 2 toxicity at 3 months after treatment appear to be negative predictors of OS.     

Increasing Yttrium-90 Dose Conformality Using Proximal Radioembolization Enabled by Distal Angiosomal Truncation for the Treatment of Hepatic Malignancy

PurposeTo evaluate safety and feasibility of improving radiation dose conformality via proximal radioembolization enabled by distal angiosomal truncation where selective administration was not practical.Materials and MethodsHepatic malignancies treated via angiosomal truncation between January 2017 and March 2019 were retrospectively evaluated. Thirty-three patients (8 women, 25 men; mean age, 62.2 y; range, 36–78 y) underwent 39 treatments. Of treatments, 74.3% (n = 29) were for hepatocellular carcinomas, 10.2% (n = 4) were for cholangiocarcinomas, and 15.4% (n = 6) were for metastatic tumors (1 colorectal adenocarcinoma, 1 pancreatic adenocarcinoma, 3 melanomas, and 1 endometroid carcinoma). Truncation was achieved using temporary embolic devices including a microvascular plug, detachable coil, gelatin slurry, and balloon microcatheter, after which proximal radioembolization was performed. Range of treatment activity was 0.47–5.75 GBq. Technetium-99m macroaggregated albumin and bremsstrahlung single photon emission computed tomography (CT)/CT threshold analysis was conducted to delineate and compare distribution of activity within the treatment angiosome before and after radioembolization.ResultsDosimetric analysis of 14 patients demonstrated a significant reduction in nontarget liver radiation exposure at 5, 20, and 40% thresholds (P = .002, P = .001, and P = .008, respectively). There were no grade 3 or higher adverse events. There was no significant change in Albumin-Bilirubin grade and Eastern Cooperative Oncology Group Performance Status (P = .09 and P = .74) before and 3 months after the procedure. Truncated arteries were patent on subsequent angiography in 11 cases and on MR angiography or CT angiography in 38 of 39 cases.ConclusionsProximal radioembolization enabled by distal angiosomal truncation is safe and decreases nontarget parenchymal radioembolization dose in cases not amenable to selective administration.     

Percutaneous Cryoablation: Safety and Efficacy for Pain Palliation of Metastases to Pleura and Chest Wall

PurposeTo assess safety and efficacy of percutaneous cryoablation for pain palliation of metastases to pleura and chest wall.Materials and MethodsThis retrospective single-center cohort study included 22 patients (27% female, mean age 63 y ± 11.4) who underwent 25 cryoablation procedures for pain palliation of 39 symptomatic metastases measuring 5.1 cm ± 1.9 (range, 2.0–8.0 cm) in pleura and chest wall between June 2012 and December 2017. Pain intensity was assessed using a numerical scale (0–10 points). Statistical tests t test, χ², and Wilcoxon signed rank were performed.ResultsPatients were followed for a median of 4.1 months (interquartile range [IQR], 2.3–10.1; range, 0.1–36.7 mo) before death or loss to follow-up. Following cryoablation, pain intensity decreased significantly by a median of 4.5 points (IQR, 2.8–6; range, 0–10 points; P = .0002 points, Wilcoxon signed rank). Pain relief of at least 3 points was documented following 18 of 20 procedures. Pain relief occurred within a median of 1 day following cryoablation (IQR, 1–2; range, 1–4 d) and lasted for a median of 5 weeks (IQR, 3–17; range, 1–34 wk). Systemic opioid requirements decreased in 11 of 22 patients (50%) by an average of 56% ± 34. Difference in morphine milligram equivalents was not significant (P = .73, Wilcoxon signed rank). No procedure-related complications occurred despite previous radiation of 7 tumors. Of 25 procedures, 22 (88%) were performed on an outpatient basis.ConclusionsPercutaneous cryoablation for metastases to pleura and chest wall can safely provide significant pain relief within days following a single session.     

Factors Associated with Hospital Length of Stay and Adverse Events following Percutaneous Ablation of Lung Tumors

PurposeTo explore the association between risk factors established in the surgical literature and hospital length of stay (HLOS), adverse events, and hospital readmission within 30 days after percutaneous image-guided thermal ablation of lung tumors.Materials and MethodsThis bi-institutional retrospective cohort study included 131 consecutive adult patients (67 men [51%]; median age, 65 years) with 180 primary or metastatic lung tumors treated in 131 sessions (74 cryoablation and 57 microwave ablation) from 2006 to 2019. Age-adjusted Charlson Comorbidity Index, sex, performance status, smoking status, chronic obstructive pulmonary disease (COPD), primary lung cancer versus pulmonary metastases, number of tumors treated per session, maximum axial tumor diameter, ablation modality, number of pleural punctures, anesthesia type, pulmonary artery–to–aorta ratio, lung densitometry, sarcopenia, and adipopenia were evaluated. Associations between risk factors and outcomes were assessed using univariable and multivariable generalized linear models.ResultsIn univariable analysis, HLOS was associated with current smoking (incidence rate ratio [IRR], 4.54 [1.23–16.8]; P = .02), COPD (IRR, 3.56 [1.40–9.04]; P = .01), cryoablations with ≥3 pleural punctures (IRR, 3.13 [1.07–9.14]; P = .04), general anesthesia (IRR, 10.8 [4.18–27.8]; P < .001), and sarcopenia (IRR, 2.66 [1.10–6.44]; P = .03). After multivariable adjustment, COPD (IRR, 3.56 [1.57–8.11]; P = .003) and general anesthesia (IRR, 12.1 [4.39–33.5]; P < .001) were the only risk factors associated with longer HLOS. No associations were observed between risk factors and adverse events in multivariable analysis. Tumors treated per session were associated with risk of hospital readmission (P = .03).ConclusionsIdentified preprocedural risk factors from the surgical literature may aid in risk stratification for HLOS after percutaneous ablation of lung tumors, but were not associated with adverse events.     

Prostatic Artery Embolization—Anatomic Predictors of Technical Outcomes

PurposeTo determine if cone-beam CT and digital subtraction angiography analysis of pelvic arterial anatomy has predictive value for radiation exposure and technical success of prostatic artery embolization (PAE).Materials and MethodsThis prospective, nonrandomized, single-center study included 104 consecutive patients with lower urinary tract symptoms secondary to benign prostatic hyperplasia. Cone-beam CT was performed in 160/208 (76.9%) hemipelves to determine prostatic artery (PA) origin. Classification of pelvic arterial tortuosity was possible in 73/104 (70.2%) patients. Learning curves of 2 interventionalists who performed 86.5% of PAEs were analyzed.ResultsTortuosity of pelvic arteries was classified as mild in 25 (34.2%) patients median age 64 years, moderate in 40 (54.8%) patients median age 69 years, and severe in 8 (11.0%) patients median age 70 years (mild vs moderate, P = .002; mild vs severe, P = .019); median fluoroscopy times were 24, 36, and 46 minutes (P = .008, P = .023); median contrast volumes were 105, 122.5, and 142 mL (P = .029, P = .064); and bilateral PAE rates were 84.0%, 77.5%, and 62.5% (P = .437), respectively. PA origin from superior vesical artery was most frequent (27.5%) and showed higher dose area product (median 402.4 vs 218 Gy ∙ cm², P = .033) and fluoroscopy time (median 42.5 vs 27 min, P = .01) compared with PA origin from obturator artery, which was least frequent. Interventionalist experience revealed significant impact on procedure times (median 159 vs 130 min, P = .006).ConclusionsTortuosity of pelvic arteries was more frequent in older patients and predicted worse technical outcomes of PAE. PA origin from obturator artery was associated with lower dose area product and fluoroscopy time, especially compared with PA origin from superior vesical artery. Interventionalist experience showed significant influence on technical outcome.     

Intra-Arterial Therapy for Unresectable Colorectal Liver Metastases: A Meta-Analysis

PurposeTo evaluate the efficacy of hepatic arterial infusion (HAI), conventional transarterial chemoembolization, drug-eluting embolic transarterial chemoembolization (DEE-TACE), transarterial radioembolization, and their combinations with systemic chemotherapy (SCT) for unresectable colorectal liver metastases.MethodsA search was conducted on Embase, Scopus, PubMed, and Web of Science for prospective nonrandomized studies and randomized controlled trials (RCTs) from inception to June 20, 2020. Survival data of patients were recovered from original Kaplan-Meier curves by exploiting a graphical reconstructive algorithm. One-stage meta-analyses were conducted for the median overall survival (OS), survival rates (SRs), and restricted mean survival time (RMST), whereas two-stage meta-analyses of proportions were conducted to determine response rates (RRs) and conversion to resection rates (CRRs).ResultsA total of 71 prospective nonrandomized studies and 21 RCTs were identified, comprising 6,695 patients. Among patients treated beyond the first-line, DEE-TACE + SCT (n = 152) had the best survival outcomes of median OS of 26.5 (95% confidence interval [CI], 22.5–29.1) months and a 3-year RMST of 23.6 (95% CI, 21.8–25.5) months. Upon further stratification by publication year, DEE-TACE + SCT appeared to consistently have the highest pooled SRs at 1 year (81.9%) and 2 years (66.1%) in recent publications (2015–2020). DEE-TACE + SCT and HAI + SCT had the highest pooled RRs of 56.7% (I² = 0.90) and 62.6% (I² = 0.87) and pooled CRRs of 35.5% (I² = 0.00) and 30.3% (I² = 0.80), respectively.ConclusionsAlbeit significant heterogeneity, the paucity of high-quality evidence, and the noncomparative nature of all analyses, the overall evidence suggests that patients treated with DEE-TACE + SCT have the best oncological outcomes and greatest potential to be converted for resection.     

Correlation and Agreement of Yttrium-90 Positron Emission Tomography/Computed Tomography with Ex Vivo Radioembolization Microsphere Deposition in the Rabbit VX2 Liver Tumor Model

PurposeTo demonstrate a stronger correlation and agreement of yttrium-90 (⁹⁰Y) positron emission tomography (PET)/computed tomography (CT) measurements with explant liver tumor dosing compared with the standard model (SM) for radioembolization.Materials and MethodsHepatic VX2 tumors were implanted into New Zealand white rabbits, with growth confirmed by 7 T magnetic resonance imaging. Seventeen VX2 rabbits provided 33 analyzed tumors. Treatment volumes were calculated from manually drawn volumes of interest (VOI) with three-dimensional surface renderings. Radioembolization was performed with glass ⁹⁰Y microspheres. PET/CT imaging was completed with scatter and attenuation correction. Three-dimensional ellipsoid VOI were drawn to encompass tumors on fused images. Tumors and livers were then explanted for inductively coupled plasma (ICP)-optical emission spectroscopy (OES) analysis of microsphere content. ⁹⁰Y PET/CT and SM measurements were compared with reference standard ICP-OES measurements of tumor dosing with Pearson correlation and Bland-Altman analyses for agreement testing with and without adjustment for tumor necrosis.ResultsThe median infused activity was 33.3 MBq (range, 5.9–152.9). Tumor dose was significantly correlated with ⁹⁰Y PET/CT measurements (r = 0.903, P < .001) and SM estimates (r = 0.607, P < .001). Bland-Altman analyses showed that the SM tended to underestimate the tumor dosing by a mean of ?8.5 Gy (CI, ?26.3–9.3), and the degree of underestimation increased to a mean of ?18.3 Gy (CI, ?38.5–1.9) after the adjustment for tumor necrosis.Conclusions⁹⁰Y PET/CT estimates were strongly correlated and had better agreement with reference measurements of tumor dosing than SM estimates.     

Effectiveness of Thermal Ablation and Stereotactic Radiotherapy Based on Stage I Lung Cancer Histology

PurposeTo assess whether the effectiveness of thermal ablation (TA) and stereotactic body radiotherapy (SBRT) as initial treatments for stage I lung cancer varies depending on the histological subtype.Materials and MethodsThe 2004–2016 National Cancer Database was queried for patients with American Joint Committee on Cancer stage I lung cancer treated with TA or SBRT. Patients <18 years, those treated with surgery or chemotherapy, or those with unknown survival and follow-up were excluded. TA and SBRT patients were 1:5 propensity score matched separately for each histological subtype to adjust for confounders. Overall survival (OS) was assessed using Cox models.ResultsA total of 28,425 patients were included (SBRT, n = 27,478; TA, n = 947). TA was more likely to be used in Caucasian patients, those with more comorbidities and smaller neuroendocrine tumors (NETs) of the lower lobe, and those whose treatment had taken place in the northeastern United States. After propensity score matching, a cohort with 4,085 SBRT and 817 TA patients with balanced confounders was obtained. In this cohort, OS for TA and SBRT was comparable (hazard ratio = 1.07; 95% confidence interval,0.98–1.18; P = .13), although it varied by histological subtypes: higher OS for TA was observed in patients with non–small cell NETs (vs SBRT hazard ratio = 0.48; 95% confidence interval, 0.24–0.95; P = .04). No significant OS differences between TA and SBRT were noted for adenocarcinomas, squamous cell carcinomas, small cell carcinomas, and non-neuroendocrine large cell carcinomas (each, P > .1).ConclusionsOS following TA and SBRT for stage I lung cancer is comparable for most histological subtypes, except that OS is longer after TA in non–small cell NETs.     

Transarterial Radioembolization with Yttrium-90 Glass Microspheres: Distribution of Residual Activity and Flow Dynamics during Administration

PurposeTo evaluate the microsphere flow dynamics and residual yttrium-90 (⁹⁰Y) activity during and after transarterial radioembolization with glass microspheres and to assess the distribution and predilection sites of residual activity in the administration devices.Materials and MethodsIn this laboratory investigation, after 18 consecutive clinical transarterial radioembolization and 4 ex vivo experimental procedures with ⁹⁰Y glass microspheres, the distribution of residual activity in the administration devices was assessed by activimeter and positron emission tomography (PET)/CT measurements. During ex vivo procedures, microsphere outflow from the administration device was assessed by dynamic scintigraphic measurements.ResultsMean residual activity was 3.4% ± 1.7 (range, 0.9%–8.8%). Calculations showed a negative correlation between relative residual activity and prescribed activity (r = −0.4258, P = .0486) and a positive correlation between absolute residual activity and prescribed activity (r = 0.5345, P = .0104). The main predilection site was the Luer-Lok microcatheter connector. Lower activities were detected in the dose vial. Flow measurements showed that more than 98% of the final injected activity was transferred to the patient with the first 20 mL of saline solution.ConclusionsResidual activity in the standard administration device for glass microsphere radioembolization is considered to be low compared with similar procedures, but is variable. The microsphere flow profile shows an initial peak, resulting in a rapid activity transfer at the beginning of the injection process. The findings may have implications for safe handling of the administration device and for dose calculation of ⁹⁰Y glass microspheres.     

Ex Vivo Evaluation of Residual Activity and Infusion Dynamics in a Commercially Available Yttrium-90 Resin Microsphere Administration System

PurposeTo evaluate the infusion dynamics and residual yttrium-90 activity during and after resin microsphere radioembolization with different injection techniques and initial activities. To assess the distribution of residual activity in the administration systems to allow optimization of the procedure and the equipment.Materials and MethodsIn a setup similar to that in standard clinical practice, radioembolization procedures were performed ex vivo. The influence of different injection techniques was assessed by comparing pulsatile and continuous injections. The influence of the absolute amount of activity to the residual activity was assessed by comparing pulsatile 0.5-GBq- with 1.0-GBq-procedures. Continuous dose rate measurements were performed. Activity distribution was determined by positron-emission tomography (PET)/CT.ResultsFifteen procedures were performed: 5 pulsatile 0.5-GBq-, 5 continuous 0.5-GBq-, and 5 pulsatile 1.0-GBq-procedures. Mean residual activity was 4.0% ± 1.7% (range 1.2%–6.6%), without statistically significant differences between injection techniques (P = .841) or between prescribed activities (P = .222). Dose-rate measurements revealed an exponential decrease of the activities in the vials with high variability. Activity fell rapidly to 32% ± 7.9% (range 23%–55%) after injection of 4 of 20 mL 5% dextrose solution. Residual activity accumulations were identified at the 3-way stopcock (100% of procedures), in the C-line (80%), at the microcatheter connector (20%), and in the A-line (6.7%), but not in the vials.ConclusionsResidual activity in a commercial administration system for resin microsphere radioembolization is variable and does not systematically depend on initial yttrium-90 activity or on injection technique. Predilection sites for residual activity were identified, which should receive special attention when performing resin transarterial radioembolization procedures, and for further administration system developments.     

Yttrium-90 Radioembolization in Intrahepatic Cholangiocarcinoma: A Multicenter Retrospective Analysis

PurposeTo report outcomes of yttrium-90 (⁹⁰Y) radioembolization in patients with unresectable intrahepatic cholangiocarcinoma (ICC).Materials and MethodsRetrospective review was performed of 115 patients at 6 tertiary care centers; 92 were treated with resin microspheres (80%), 22 were treated with glass microspheres (19%), and 1 was treated with both. Postintervention outcomes were compared between groups with χ² tests. Survival after diagnosis and after treatment was assessed by Kaplan–Meier method.ResultsGrade 3 laboratory toxicity was observed in 4 patients (4%); no difference in toxicity profile between resin and glass microspheres was observed (P = .350). Clinical toxicity per Society of Interventional Radiology criteria was noted in 29 patients (25%). Partial response per Response Evaluation Criteria In Solid Tumors 1.1 was noted in 25% of patients who underwent embolization with glass microspheres and 3% of patients who were treated with resin microspheres (P = .008). Median overall survival (OS) from first diagnosis was 29 months (95% confidence interval [CI], 21–37 mo) for all patients, and 1-, 3-, and 5-year OS rates were 85%, 31%, and 8%, respectively. Median OS after treatment was 11 months (95% CI, 8–13 mo), and 1- and 3-year OS rates were 44% and 4%, respectively. These estimates were not significantly different between resin and glass microspheres (P = .730 and P = .475, respectively). Five patients were able to undergo curative-intent resection after ⁹⁰Y radioembolization (4%).ConclusionsThis study provides observational data of treatment outcomes after ⁹⁰Y radioembolization in patients with unresectable ICC.     

Resolution of Pain after Percutaneous Image-Guided Cryoablation of Extraperitoneal Endometriosis

PurposeTo retrospectively evaluate the relief of pain after percutaneous image-guided cryoablation of symptomatic extraperitoneal endometriosis (EE).Material and MethodsFrom 2017 to 2022, cryoablation of EE was performed at a single institution on a total of 47 lesions in 42 consecutive patients (median age, 37 years; interquartile range [IQR], 33–39.5 years). Patient and procedural characteristics were reviewed retrospectively. Tolerance and outcomes in terms of pain and patient satisfaction were evaluated.ResultsThe median follow-up duration was 13.5 months (IQR, 1.1–37.7 months) after cryoablation. The median pain-free survival rate was 93.8% (95% confidence interval [CI], 77.3–98.4) at 6 months and 82.7% (95% CI, 58.8–93.5) after 12 months. Pain decreased from a median of 8/10 (IQR, 7–9) on the visual analog scale to 0/10 (IQR, 0–1) at the last follow-up (P < .0001). The median Patient Global Impression of Change score recorded at the last follow-up was 1/7 (IQR, 1–2). The efficacy rate of cryoablation to avoid secondary surgery was 92.8% (39/42) per patient and 93.6% (44/47) per nodule treated. Four patients (9.5%, 4/42) experienced an adverse event in the days following the procedure, and 1 patient (2%) experienced a severe adverse event.ConclusionsPercutaneous cryoablation is safe and effective in significantly reducing pain and obtaining local control of EE.     

Transarterial Yttrium-90 Radioembolization of Hepatocellular Carcinoma Perfused by the Cystic Artery: Multi-institutional Feasibility Study

PurposeTo assess the safety and efficacy of transarterial yttrium-90 radioembolization via the cystic artery for patients with hepatocellular carcinoma (HCC) adjacent to the gallbladder with cystic artery supply.Materials and MethodsThis retrospective study included 17 patients treated at 4 institutions. Patients with HCC perfused by the cystic artery who received ablative-dose radioembolization were included. Median tumor size was 3.8 cm (range, 2.0–8.8 cm). Fourteen patients (82%) had Child–Pugh class A cirrhosis and 3 (18%) had class B cirrhosis. Adverse events, tumor response, and time to progression were analyzed.ResultsMedian dose to the tissue perfused by the cystic artery was 340 Gy (range, 200–720 Gy). There were no occurrences of acute cholecystitis warranting invasive intervention. Four patients (24%) experienced transient right upper quadrant pain, with symptom resolution within 3 mo. Six patients (35%) exhibited gallbladder wall edema on follow-up imaging. Two (12%) and 0 grade 3/4 increases in alkaline phosphatase and bilirubin were observed, respectively. Follow-up imaging demonstrated complete response in 13 target tumors (76%) and partial response in 4 (24%). There were no cases of target tumor progression during a median follow-up of 9 mo (range, 3–72 mo).ConclusionsDirect infusion of ⁹⁰Y microspheres via the cystic artery appears to have an acceptable safety profile, without resulting in acute cholecystitis warranting invasive intervention. In selected patients with HCC in whom other treatments may be contraindicated and the tumor is supplied via the cystic artery, treatment with selective ablative radioembolization can be considered.     

Transarterial Radioembolization versus Transarterial Chemoembolization Plus Percutaneous Ablation for Unresectable,Solitary Hepatocellular Carcinoma of ≥3 cm: A Propensity Score–Matched Study

PurposeTo compare the safety and effectiveness of transarterial radioembolization (TARE) and transarterial chemoembolization with drug-eluting embolic agents combined with percutaneous ablation (transarterial chemoembolization [TACE] + ablation) in the treatment of treatment-naïve, unresectable, solitary hepatocellular carcinoma (HCC) of ≥3 cm.Materials and MethodsTwenty-nine patients with treatment-naïve, unresectable, solitary HCC of ≥3 cm received combined TACE + ablation, and 40 patients received TARE at a single institution. Local tumor response, tumor progression-free survival (PFS), overall survival, need for reintervention, bridge to transplant, and major complications were compared. Clinical variables and outcomes were compared before and after propensity score matching (PSM).ResultsBefore PSM, patients who underwent TARE had a larger tumor size (3.7 vs 5.5 cm; P = .0005) and were older (61.5 vs 69.3 years; P = .0014). After PSM, there was no difference in baseline characteristics between the 2 groups, with the mean tumor sizes measuring 3.9 and 4.1 cm in the TACE + ablation and TARE cohorts, respectively. After PSM (n = 19 in each group), no statistically significant difference was observed in local radiological response (disease control rates, 100% vs 94.7%; P = .31), survival (subdistribution hazard ratio [SHR], 0.71; 95% confidence interval [CI], 0.28–1.80; P = .469), PFS (SHR, 0.61; 95% CI, 0.21–1.71; P = .342), bridge to transplant (21.1% vs 31.6%, P = .46), and major adverse event rates (15.8% vs 10.5%, P = .63) between the 2 groups. The mean total number of locoregional interventions was higher in the TACE + ablation cohort (1.9 vs 1.3 sessions, P = .02), with an earlier median reintervention trend (SHR, 0.61; 95% CI, 0.20–1.32; P = .167).ConclusionsThe present study showed that TARE and the combination of TACE and ablation are comparable in safety and effectiveness for treating treatment-naïve, unresectable, solitary HCC of ≥3 cm.