Safety and Diagnostic Efficacy of Image-Guided Biopsy of Small Renal Masses.

INTRODUCTION: Image-guided renal mass biopsy is gaining increased diagnostic acceptance, but there are limited data concerning the safety and diagnostic yield of biopsy for small renal masses (≤4 cm). This study evaluated the safety, diagnostic yield, and management after image-guided percutaneous biopsy for small renal masses. METHODS: A retrospective IRB-approved study was conducted on patients who underwent renal mass biopsy for histopathologic diagnosis at a single center from 2015 to 2021. Patients with a prior history of malignancy or a renal mass >4 cm were excluded. Descriptive statistics were used to summarize patient demographics, tumor size, the imaging modality used for biopsy, procedure details, complications, pathological diagnosis, and post-biopsy management. A biopsy was considered successful when the specimen was sufficient for diagnosis without need for a repeat biopsy. Complications were graded according to the SIR classification of adverse events. A chi-squared test (significance level set at p ≤ 0.05) was used to compare the success rate of biopsies in different lesion size groups. RESULTS: A total of 167 patients met the inclusion criteria. The median age was 65 years (range: 26-87) and 51% were male. The median renal mass size was 2.6 cm (range: one-four). Ultrasound was solely employed in 60% of procedures, CT in 33%, a combination of US/CT in 6%, and MRI in one case. With on-site cytopathology, the median number of specimens obtained per procedure was four (range: one-nine). The overall complication rate was 5%. Grade A complications were seen in 4% (n = 7), consisting of perinephric hematoma (n = 6) and retroperitoneal hematoma (n = 1). There was one grade B complication (0.5%; pain) and one grade D complication (0.5%; pyelonephritis). There was no patient mortality within 30 days post-biopsy. Biopsy was successful in 88% of cases. A sub-group analysis showed a success rate of 85% in tumors <3 cm and 93% in tumors ≥3 cm (p = 0.01). Pathological diagnoses included renal cell carcinoma (65%), oncocytoma (18%), clear cell papillary renal cell tumors (9%), angiomyolipoma (4%), xanthogranulomatous pyelonephritis (1%), lymphoma (1%), high-grade papillary urothelial carcinoma (1%), and metanephric adenoma (1%), revealing benign diagnosis in 30% of cases. The most common treatment was surgery (40%), followed by percutaneous cryoablation (22%). In total, 37% of patients were managed conservatively, and one patient received chemotherapy. CONCLUSION: This study demonstrates the safety and diagnostic efficacy of image-guided biopsy of small renal masses. The diagnostic yield was significantly higher for masses 3-4 cm in size compared to those <3 cm. The biopsy results showed a high percentage of benign diagnoses and informed treatment decisions in most patients.

Acute Pancreatitis following Percutaneous Electrohydraulic Lithotripsy.

The gold-standard treatment of acute calculous cholecystitis is cholecystectomy. For patients not suitable for surgery, endoscopic or percutaneous techniques can be used for gallbladder decompression. The national percutaneous cholecystostomy rates have increased by 567% from 1994 to 2009*. Some of these patients are still not surgical candidates after the acute cholecystitis episode has resolved. Hence, it is crucial to have a management plan in place for such patients. There are several peroral endoscopic treatment options available, including ultrasound-guided transmural drainage, lithotripsy, and transpapillary stenting**. Furthermore, due to the advent of percutaneous biliary endoscopes, interventional radiology (IR) can now perform percutaneous lithotripsy and gallstone removal followed by cystic duct stenting. This method aims to internalize gallbladder drainage without the need for a long-term external cholecystostomy tube. Acute pancreatitis is a rare complication that can arise following interventions involving the biliary and cystic ducts. Acute pancreatitis can occur after retrograde ampullary manipulation during endoscopic retrograde cholangiopancreatography. However, this can sometimes happen after percutaneous antegrade interventions performed by IR. In this report, we will examine a rare complication that occurred in a patient with acute calculous cholecystitis: acute pancreatitis following percutaneous electrohydraulic lithotripsy with cystic duct stenting performed by IR.

Yttrium-90 Radiation Segmentectomy in Oligometastatic Secondary Hepatic Malignancies.

PURPOSE: To evaluate the safety and efficacy of yttrium-90 (90Y) radiation segmentectomy (RS) in the treatment of oligometastatic secondary hepatic malignancies. MATERIALS AND METHODS: This institutional review board-approved retrospective study evaluated 16 patients with oligometastatic secondary hepatic malignancies who were treated with RS. The median patient age was 61.9 years (range, 38.6-85.7 years). Of the 16 patients, 11 (68.8%) presented with solitary lesions. The median index tumor size was 3.1 cm (95% CI, 2.3-3.9). Primary outcomes were evaluation of clinical and biochemical toxicities using National Cancer Institute Common Terminology Criteria for Adverse Events, version 5.0, and imaging response using Response Evaluation Criteria in Solid Tumors, version 1.1. Secondary outcomes were time to progression (TTP) and overall survival (OS) as estimated by the Kaplan-Meier method. RESULTS: Clinical Grade 3 toxicities were limited to 1 (6.7%) patient who experienced fatigue, abdominal pain, nausea, and vomiting. Biochemical Grade 3 toxicities occurred in 1 (6.7%) patient who experienced lymphopenia. No Grade 4 clinical or biochemical toxicities were identified. Disease control was achieved in 14 (93.3%) of 15 patients. The median TTP of the treated tumor was 72.9 months (95% CI, 11.2 to no estimate). The median OS was 60.9 months (95% CI, 24.7 to no estimate). CONCLUSIONS: 90Y RS displayed an excellent safety profile and was effective in achieving a high disease control rate in the treatment of oligometastatic secondary hepatic malignancies.

Yttrium-90 Radioembolization of Unresectable Intrahepatic Cholangiocarcinoma: Long-Term Follow-up for a 136-Patient Cohort.

PURPOSE: Unresectable intrahepatic cholangiocarcinoma (ICC) signifies a poor prognosis with limited treatment options beyond systemic chemotherapy. This study's purpose was to evaluate the safety, efficacy, and potential for downstaging to resection of yttrium-90 (Y90) radioembolization for treatment of unresectable ICC. MATERIALS AND METHODS: From 2004 to 2020, 136 patients with unresectable ICC were treated with radioembolization at a single institution. Retrospective review was performed of a prospectively collected database. Outcomes were (1) biochemical and clinical toxicities, (2) local tumor response, (3) time to progression, and (4) overall survival (OS) after Y90. Univariate/multivariate survival analyses were performed. A subgroup analysis was performed to calculate post-resection recurrence and OS in patients downstaged to resection after Y90. RESULTS: Grade 3+ clinical and biochemical toxicities were 7.6% (n = 10) and 4.9% (n = 6), respectively. Best index lesion response was complete response in 2 (1.5%), partial response in 42 (32.1%), stable disease in 82 (62.6%), and progressive disease in 5 (3.8%) patients. Median OS was 14.2 months. Solitary tumor (P < 0.001), absence of vascular involvement (P = 0.009), and higher serum albumin (P < 0.001) were independently associated with improved OS. Eleven patients (8.1%) were downstaged to resection and 2 patients (1.5%) were bridged to transplant. R0-resection was achieved in 8/11 (72.7%). Post-resection median recurrence and OS were 26.3 months and 39.9 months, respectively. CONCLUSION: Y90 has an acceptable safety profile and high local disease control rates for the treatment of unresectable ICC. Downstaging to resection with > 3 years survival supports the therapeutic role of Y90 for unresectable ICC. LEVEL OF EVIDENCE: Level 3, single-arm single-center cohort study.

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

PURPOSE: To 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 METHODS: Hepatic 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. RESULTS: The 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. CONCLUSIONS: 90Y PET/CT estimates were strongly correlated and had better agreement with reference measurements of tumor dosing than SM estimates.

Single-Center Retrospective Review of Radiofrequency Wire Recanalization of Refractory Central Venous Occlusions.

PURPOSE: To retrospectively review the effectiveness and safety of radiofrequency (RF) wire recanalization of refractory central venous occlusions (CVOs) and compare recurrent and nonrecurrent CVOs in terms of patient and occlusion characteristics. MATERIALS AND METHODS: Twenty CVOs were treated in 18 patients (age 40 y ± 13; 9 women) with 11 superior vena cava (SVC) or brachiocephalic vein occlusions (ie, supradiaphragmatic) and 9 inferior vena cava or iliac vein occlusions (ie, infradiaphragmatic). Indications included pain, edema, ulceration, and/or dialysis arteriovenous fistula dysfunction peripheral to the CVO(s). All patients had multiple venous thrombotic risk factors, including mechanical venous compression, endothelial injury, and/or coagulopathies. CVO traversal was first attempted with standard and advanced techniques before RF wire recanalization and followed up with computed tomographic venography and clinic visits approximately 1, 3, 6, and 12 months after treatment. RESULTS: Sixteen CVOs (80%) were successfully transversed and associated with symptom relief. One major complication occurred involving SVC perforation into the pericardial space. Primary CVO patency rate was 56% at a median follow-up of 14.1 months (interquartile range [IQR], 9.2-20.0 mo). Recurrent CVOs tended to be infradiaphragmatic (71% vs 12% for supradiaphragmatic; P = .02), longer (12.9 cm ± 10.0 vs 2.3 cm ± 1.3; P < .01), and associated with implanted venous stents, filters, or cardiac pacer/defibrillator leads (86% vs 22%; P = .01). Median time to restenosis/occlusion was 1.5 months (IQR, 1.1-6.1 mo). CONCLUSIONS: RF wire recanalization is a relatively effective and safe option for refractory CVOs. Patients with longer, infradiaphragmatic CVOs associated with indwelling devices may require closer follow-up for CVO recurrence.

Analysis of the RENAL and mRENAL Scores and the Relative Importance of Their Components in the Prediction of Complications and Local Progression after Percutaneous Renal Cryoablation.

PURPOSE: To determine if modified RENAL (mRENAL) score and its individual components have superior predictive value relative to the RENAL nephrometry score in prediction of complications and recurrence after percutaneous renal cryoablation. MATERIALS AND METHODS: Primary masses treated with CT-guided percutaneous renal cryoablation between June 2007 and May 2016 were retrospectively reviewed. RENAL and mRENAL scores were used to stratify masses into low, medium, and high complexity tertiles. Complications were characterized by SIR criteria. Predictors of complications and local progression were analyzed using multivariate logistic regression and Kaplan-Meier analysis. RESULTS: There were 95 renal cryoablation procedures in 86 patients. Of ablations, 89 had at least 1 follow-up imaging study, with median follow-up of 29 months. There were 11 (12.4%) complications, including 5 (6.5%) major complications. Mass complexity, as measured by mRENAL complexity tertile, was associated with increased risk of complications on multivariate analysis (P = .045). Endophytic location was the only individual ordinal component of the RENAL and mRENAL scores associated with complications (P = .021). Local progression occurred in 7 (8.3%) masses. Complexity as measured by either scoring system was not associated with local progression. Only diameter > 3 cm was associated with increased risk of local progression (hazard ratio = 9.9, 95% confidence interval = 2.1-45, P = .003). CONCLUSIONS: mRENAL score was predictive of complications and tumor size was predictive of recurrence. Use of mRENAL score for complications and tumor size for recurrence should allow for simpler risk stratification and more accurate patient counseling.

Percutaneous Cryoablation for the Treatment of Primary and Metastatic Lung Tumors: Identification of Risk Factors for Recurrence and Major Complications.

PURPOSE: To identify risk factors for local recurrence and major complications associated with percutaneous cryoablation of lung tumors. MATERIALS AND METHODS: All cases between April 2007 and September 2014 at 1 institution were retrospectively reviewed. Procedures were performed using computed tomography guidance and a double freeze-thaw protocol. Tumor progression was determined via World Health Organization guidelines, and complications were classified using SIR reporting standards. Measures of efficacy were calculated via Kaplan-Meier analysis. Predictors of local progression and major complications were identified by Cox proportional hazards and logistic regression. RESULTS: There were 47 tumors (25 primary, 22 metastatic) treated with median follow-up of 11.1 months. Mean diameter before treatment was 2.4 cm, and an average of 2.1 cryoprobes were used per procedure. Major complications (most commonly, pneumothorax requiring chest tube) occurred in 12 (25%) cases, and minor complications occurred in 13 (27%) cases. Median time to local progression was 14 months (16 mo for primary tumors and 10 mo for metastatic tumors), and median overall survival was 33 months (43 mo for patients with primary tumors and 22 mo for patients with metastatic tumors). On multivariate analysis, tumor diameter > 3 cm was associated with local progression (hazard ratio = 3.2, P = .013), and use of multiple cryoprobes (relative risk [RR] = 7.2, P = .045) and previous local therapy (RR = 15, P = .030) were associated with major complications. CONCLUSIONS: Percutaneous cryoablation of lung tumors is technically feasible with a complication rate comparable to other percutaneous ablation techniques. Percutaneous cryoablation is more efficacious and has fewer complications when offered to patients with small, previously untreated lesions.

Single- versus Triple-Drug Chemoembolization for Hepatocellular Carcinoma: Comparing Outcomes by Toxicity, Imaging Response, and Survival.

PURPOSE: To determine the efficacy of single- versus triple-drug chemoembolization for the treatment of hepatocellular carcinoma, as measured by toxicity, tumor response, time to progression (TTP), and overall survival (OS). MATERIALS AND METHODS: A single-center retrospective review was performed on 337 patients who underwent chemoembolization over a 14-year period; 172 patients underwent triple-drug conventional transarterial chemoembolization, and 165 patients underwent single-agent doxorubicin chemoembolization. Imaging characteristics and clinical follow-up after conventional transarterial chemoembolization were evaluated to determine TTP. Imaging response was determined per World Health Organization and European Association for the Study of Liver criteria. OS from time of first chemoembolization was calculated. RESULTS: Median TTP was similar between groups: 7.9 months (95% confidence interval [CI], 7.1-9.4) and 6.8 months (95% CI, 4.6-8.6) for triple- and single-drug regimens, respectively (P > .05). For single-agent conventional transarterial chemoembolization, median OS varied significantly by Barcelona Clinic for Liver Cancer (BCLC) stage: A, 40.8 months; B, 36.4 months; C, 10.9 months (P < .01). Median OS for triple-drug therapy also varied significantly by BCLC: A, 28.9 months; B, 18.1 months; C, 9.0 months (P < .01). Single-drug conventional transarterial chemoembolization demonstrated longer median OS compared with triple-drug therapy (P < .05) for BCLC A/B patients. CONCLUSIONS: Single-agent chemoembolization with doxorubicin and ethiodized oil demonstrates acceptable efficacy as measured by TTP and OS. Results compare favorably with traditional triple-drug therapy.

Yttrium-90 radioembolization stops progression of targeted breast cancer liver metastases after failed chemotherapy.

PURPOSE: To determine, in an open-label, retrospective report, the safety and effectiveness of locoregional therapy with yttrium-90 ((90)Y) radioembolization for patients with progressing breast cancer liver metastases (BCLMs) despite multi-agent chemotherapy. MATERIALS AND METHODS: Seventy-five patients with progressing BCLMs and stable extrahepatic disease were treated with radioembolization at a single institution. Retrospective review of a prospectively collected database was performed to evaluate clinical and biochemical toxicities, tumor response, overall survival (OS), and time to progression. Radiologic response assessments included Response Evaluation Criteria In Solid Tumors in primary index lesions and metabolic activity on positron emission tomography (PET). Univariate and multivariate analyses were performed. RESULTS: The mortality rate at 30 days was 4% (n = 3). Clinical toxicity and hyperbilirubinemia of grade 3 or worse occurred in 7.6% (n = 5) and 5.9% of patients (n = 4), respectively. Partial response (PR) was seen in 35.3% of patients (n = 24), stable disease (SD) in 63.2% (n = 43), and progressive disease in 1.5% (n = 1). PET imaging was available in 25 patients, and 21 (84%) had a complete response, PR, or SD. The median OS was 6.6 months (95% confidence interval [CI], 5.0-9.2 mo). The hazard ratio (HR) for OS on multivariate analysis was 0.39 (95% CI, 0.23-0.66) for tumor burden less than 25% compared with greater burden. Elevated bilirubin levels were shown to reduce OS. The HR for hepatic progression was 0.22 (95% CI, 0.05-0.98) for solitary versus multifocal disease. CONCLUSIONS: Locoregional therapy with (90)Y radioembolization is safe and stops or delays the progression of targeted chemorefractory BCLMs. Adverse prognosticators were identified.

Perfusion reduction at transcatheter intraarterial perfusion MR imaging: a promising intraprocedural biomarker to predict transplant-free survival during chemoembolization of hepatocellular carcinoma.

PURPOSE: To investigate the predictive value of transcatheter intraarterial perfusion (TRIP) magnetic resonance (MR) imaging-measured tumor perfusion changes during transarterial chemoembolization on transplant-free survival (TFS) in patients with unresectable hepatocellular carcinoma (HCC). MATERIALS AND METHODS: This HIPAA-compliant prospective study was approved by the institutional review board. Written informed consent was obtained from all patients. Fifty-one consecutive adult patients with surgically unresectable single or multifocal measurable HCC and adequate laboratory parameters who underwent chemoembolization in a combined MR imaging-interventional radiology suite between February 2006 and June 2010 were studied. Tumor perfusion changes during chemoembolization were measured by using TRIP MR imaging with area under the time-signal intensity curve calculation. The end point of the study was TFS. The authors assessed the correlation between the percentage perfusion reduction in the tumor during chemoembolization and TFS by using univariate and multivariate analyses. RESULTS: Fifty patients (mean age, 61 years; 39 men aged 42-87 years [mean age, 61 years] and 11 women aged 49-83 years [mean age, 62 years]) were eligible for the analysis. Patients with 35%-85% intraprocedural tumor area under the time-signal intensity curve reduction (n = 32) showed significantly improved median TFS compared with patients with an area under the time-signal intensity curve reduction outside this range (n = 18) (16.6 months [95% confidence interval: 11.2, 22.0 months] vs 9.3 months [95% confidence interval: 6.6, 12.0 months], respectively; P = .046; hazard ratio: 0.46; 95% confidence interval: 0.21, 1.00). The cumulative TFS rates in the 35%-85% and less than 35% or more than 85% perfusion reduction groups at 1, 2, and 5 years after chemoembolization were 66.4%, 42.2%, and 28.2% versus 33.8%, 16.9%, and 0%, respectively. CONCLUSION: The study shows evidence of an association between intraprocedural tumor perfusion reduction during chemoembolization and TFS and suggests the utility of TRIP MR imaging- measured tumor perfusion reduction as an intraprocedural imaging biomarker during chemoembolization.

Unresectable solitary hepatocellular carcinoma not amenable to radiofrequency ablation: multicenter radiology-pathology correlation and survival of radiation segmentectomy.

UNLABELLED: Resection and radiofrequency ablation (RFA) are treatment options for hepatocellular carcinoma (HCC) <3 cm; there is interest in expanding the role of ablation to 3-5 cm. RFA is considered high-risk when the lesion is in close proximity to critical structures. Combining microcatheter technology and the localized emission properties of Y90, highly selective radioembolization is a possible alternative to RFA in such cases. We assessed the efficacy (response, radiology-pathology correlation, survival) of radiation segmentectomy in solitary HCC not amenable to RFA or resection. Patients with treatment-naïve, unresectable, solitary HCC ≤ 5 cm not amenable to RFA were included in this multicenter study. Administered dose, response rate, time-to-progression (modified Response Evaluation Criteria in Solid Tumors [mRECIST]), radiology-pathology correlation and long-term survival were assessed. In all, 102 patients were included in this study. mRECIST complete response (CR), partial response (PR), and stable disease (SD) were 47/99 (47%), 39/99 (39%), and 12/99 (12%), respectively. Median time-to-disease-progression was 33.1 months. In all, 33/102 (32%) patients were transplanted with a median (interquartile range [IQR]) time-to-transplantation of 6.3 months (3.6-9.7). Pathology revealed 100% and 50-99% necrosis in 17/33 (52%) and 16/33 (48%), respectively. Median overall survival was 53.4 months. Univariate analysis demonstrated a survival benefit for Eastern Cooperative Oncology Group (ECOG) 0 patients. In the multivariate model, age <65, ECOG 0, and Child-Pugh A were characteristics associated with longer survival. CONCLUSION: Radiation segmentectomy is an effective technique with a favorable risk profile and radiology-pathology outcomes for solitary HCC ≤ 5 cm. This approach may allow for treatment of HCC in difficult locations. Since RFA and resection are not options given tumor location, there appears to be a strong rationale for this technique as second choice.

Sustained safety and efficacy of extended-shelf-life (90)Y glass microspheres: long-term follow-up in a 134-patient cohort.

PURPOSE: To validate our initial pilot study and confirm sustained safety and tumor response of extended-shelf-life (90)Y glass microspheres. We hypothesized that for the same planned tissue dose, the increase in number of glass microspheres (decayed to the second week of their allowable shelf-life) administered for the same absorbed dose would result in better tumor distribution of the microspheres without causing additional adverse events. METHODS: Between June 2007 and January 2010, 134 patients underwent radioembolization with extended-shelf-life (90)Y glass microspheres; data from 84 new patients were combined with data from our 50-patient pilot study cohort. Baseline and follow-up imaging and laboratory data were obtained 1 and 3 months after therapy and every 3 months thereafter. Clinical and biochemical toxicities were prospectively captured and categorized according to the Common Terminology Criteria. Response in the index lesion was assessed using WHO and EASL guidelines. RESULTS: The mean delivered radiation dose was 123 Gy to the target liver tissue. The mean increase in number of microspheres with this approach compared to standard (90)Y glass microsphere dosimetry was 103%, corresponding to an increase from 3.84 to 7.78 million microspheres. Clinical toxicities included fatigue (89 patients, 66%), abdominal pain (49 patients, 36.6%), and nausea/vomiting (25 patients, 18.7%). Grade 3/4 bilirubin toxicity was seen in three patients (2%). Two (1%) of the initial 50-patient cohort showed gastroduodenal ulcers; gastroduodenal ulcers were not seen in any of the subsequent 84 patients. According to WHO and EASL guidelines, response rates were 48% and 57%, respectively, and 21% demonstrated a complete EASL response. CONCLUSION: This study showed sustained safety and efficacy of extended-shelf-life (90)Y glass microspheres in a larger, 134-patient cohort. The increase in number of microspheres administered theoretically resulted in better tumor distribution of the microspheres without an increase in adverse events.

Radioembolization for neuroendocrine liver metastases: safety, imaging, and long-term outcomes.

PURPOSE: To present long-term outcomes on the safety and efficacy of Yttrium-90 radioembolization in the treatment of unresectable hepatic neuroendocrine metastases refractory to standard-of-care therapy. METHODS AND MATERIALS: This study was approved by our institutional review board and was compliant with the Health Insurance Portability and Accountability Act. Forty patients with hepatic neuroendocrine metastases were treated with (90)Y radioembolization at a single center. Toxicity was assessed using National Cancer Institute Common Terminology Criteria v3.0. Response to therapy was assessed by World Health Organization (WHO) guidelines for size and European Association for the Study of the Liver disease (EASL) guidelines for necrosis. Time to response and overall survival were calculated using the Kaplan-Meier method. Univariate and multivariate analyses were performed. RESULTS: The median dose was 113 Gy (29-299 Gy). Clinical toxicities included fatigue (63%), nausea/vomiting (40%), abdominal pain (18%), fever (8%), diarrhea and weight loss (5%); Grade 3 and 4 bilirubin toxicities were experienced by 2 patients and 1 patient, respectively. Different responses were noted by WHO (complete response, 1.2%; partial response, 62.7%) and EASL (complete response, 20.5%; partial response, 43.4%). Median time to response was 4 and 4.9 months by lesion and patient, respectively. The 1-, 2-, and 3-year overall survival rates were 72.5%, 62.5%, and 45%, respectively. Eastern Cooperative Oncology Group (ECOG) performance score 0 (p < 0.0001), tumor burden ≤25% (p = 0.0019), albumin ≥3.5 g/dL (p = 0.017), and bilirubin ≤1.2 mg/dL (p = 0.002) prognosticated survival on univariate analysis; only ECOG performance score 0 and bilirubin ≤1.2 mg/dL prognosticated better survival outcome on multivariate analysis (p = 0.0001 and p = 0.02). CONCLUSION: Yttrium-90 therapy for hepatic neuroendocrine metastases leads to satisfactory tumor response and patient survival with low toxicity, in line with published national guidelines recommending radioembolization as a potential option for unresectable hepatic neuroendocrine metastases.

Quantitative 4D transcatheter intraarterial perfusion MRI for standardizing angiographic chemoembolization endpoints.

OBJECTIVE: The purpose of this study was to test the hypothesis that subjective angiographic endpoints during transarterial chemoembolization (TACE) of hepatocellular carcinoma are consistent and correlate with objective intraprocedural reductions in tumor perfusion determined with quantitative 4D transcatheter intraarterial perfusion MRI. SUBJECTS AND METHODS: In this prospective study, 18 consecutively registered patients underwent TACE in a combined MRI-interventional radiology suite. Three board-certified interventional radiologists independently graded the angiographic endpoint of each procedure using a previously described subjective angiographic chemoembolization endpoint scale. A consensus endpoint rating was established for each patient. Patients underwent quantitative 4D transcatheter intraarterial perfusion MRI immediately before and after TACE, and mean whole tumor perfusion was calculated from the images. Consistency of subjective angiographic endpoint ratings between observers was evaluated with the intraclass correlation coefficient. The relation between the endpoint ratings and intraprocedural transcatheter intraarterial perfusion MRI changes was evaluated with the Spearman rank correlation coefficient. RESULTS: The subjective angiographic chemoembolization endpoint rating scale showed very good consistency among all observers (intraclass correlation coefficient, 0.80). The consensus endpoint rating correlated significantly with both absolute (r = 0.54, p = 0.022) and percentage (r = 0.85, p < 0.001) reduction in intraprocedural perfusion. CONCLUSION: The subjective angiographic chemoembolization endpoint rating scale shows very good consistency between raters and significantly correlates with objectively measured intraprocedural perfusion reductions during TACE. These results support the use of the scale as a standardized alternative method in quantitative 4D transcatheter intraarterial perfusion MRI to classify patients on the basis of embolic endpoints of TACE.

Four-dimensional transcatheter intraarterial perfusion MRI monitoring of radiofrequency ablation of rabbit VX2 liver tumors.

PURPOSE: To investigate the hypothesis that four-dimensional (4D) transcatheter intraarterial perfusion (TRIP) magnetic resonance imaging (MRI) can quantify immediate perfusion changes after radiofrequency (RF) ablation in rabbit VX2 liver tumors. MATERIALS AND METHODS: Nine New Zealand White rabbits were used to surgically implant VX2 liver tumors. During ultrasound-guided RF ablation, tumors received either a true or sham ablation. After selective catheterization of the left hepatic artery under x-ray fluoroscopy, we acquired pre- and post-RF ablation 4D TRIP MR images using 3 mL of 2.5% intraarterial gadopentetate dimeglumine. Two regions-of-interest were drawn upon each tumor to generate signal-intensity time curves. Area under the curve (AUC) was calculated to provide semiquantitative perfusion measurements that were compared using a paired t-test (α = 0.05). Ablated tissue was visually confirmed on pathology using Evans blue dye. RESULTS: Mean AUC perfusion of VX2 tumors for the true ablation group decreased by 92.0% (95% confidence interval [CI]: 83.3%-100%), from 1913 (95% CI: 1557, 2269) before RF ablation to 76.6 (95% CI: 18.4, 134.8) after RF ablation (a.u., P < 0.001). Sham-ablated tumors demonstrated no significant perfusion changes. CONCLUSION: 4D TRIP MRI can quantify liver tumor perfusion reductions in VX2 rabbits after RF ablation. This MRI technique can potentially be used to improve tumor response assessment at the time of RF ablation.

Intraprocedural transcatheter intra-arterial perfusion MRI as a predictor of tumor response to chemoembolization for hepatocellular carcinoma.

RATIONALE AND OBJECTIVES: To prospectively test the hypothesis that transcatheter intraarterial perfusion magnetic resonance imaging (TRIP-MRI) measured semiquantitative perfusion reductions during transcatheter arterial chemoembolization of hepatocellular carcinoma (HCC) are associated with tumor response. MATERIALS AND METHODS: Twenty-eight patients (mean age 63 years; range 47-87 years) with 29 tumors underwent chemoembolization in a combined magnetic resonance interventional radiology suite. Intraprocedural tumor perfusion reductions during chemoembolization were monitored using TRIP-MRI. Pre- and postchemoembolization semiquantitative area under the time-signal enhancement curve (AUC) tumor perfusion was measured. Mean tumor perfusion pre- and postchemoembolization were compared using a paired t-test. Imaging follow-up was performed 1-3 months after chemoembolization. We studied the relationship between short-term tumor imaging response and intraprocedural perfusion reductions using univariate and multivariate analysis. RESULTS: Intraprocedural AUC perfusion value decreased significantly after chemoembolization (342.1 vs. 158.6 arbitrary unit, P < .001). Twenty-six patients with 27 HCCs (n = 27) had follow-up imaging at mean 39 days postchemoembolization. Favorable response was present in 67% of these treated tumors according to necrosis criteria. Fifteen of 16 (94%) tumors with 25%-75% perfusion reductions showed necrosis treatment response compared to only 3 of 11 (27%) tumors with perfusion reductions outside the above range (P = .001). Multivariate logistic regression indicated that intraprocedural tumor perfusion reduction and Child-Pugh class were independent factors associated significantly with tumor response (P = .012 and .047, respectively). CONCLUSION: TRIP-MRI can successfully measure semiquantitative changes in HCC perfusion during chemoembolization. Intraprocedural tumor perfusion reductions are associated with future tumor response.

Radiographic response to locoregional therapy in hepatocellular carcinoma predicts patient survival times.

BACKGROUND & AIMS: It is not clear whether survival times of patients with hepatocellular carcinoma (HCC) are associated with their response to therapy. We analyzed the association between tumor response and survival times of patients with HCC who were treated with locoregional therapies (LRTs) (chemoembolization and radioembolization). METHODS: Patients received LRTs over a 9-year period (n = 463). Patients with metastases, portal venous thrombosis, or who had received transplants were excluded; 159 patients with Child-Pugh B7 or lower were analyzed. Response (based on European Association for the Study of the Liver [EASL] and World Health Organization [WHO] criteria) was associated with survival times using the landmark, risk-of-death, and Mantel-Byar methodologies. In a subanalysis, survival times of responders were compared with those of patients with stable disease and progressive disease. RESULTS: Based on 6-month data, in landmark analysis, responders survived longer than nonresponders (based on EASL but not WHO criteria: P = .002 and .0694). The risk of death was also lower for responders (based on EASL but not WHO criteria: P = .0463 and .707). Landmark analysis of 12-month data showed that responders survived longer than nonresponders (P < .0001 and .004, based on EASL and WHO criteria, respectively). The risk of death was lower for responders (P = .0132 and .010, based on EASL and WHO criteria, respectively). By the Mantel-Byar method, responders had longer survival than nonresponders, based on EASL criteria (P < .0001; P = .596 with WHO criteria). In the subanalysis, responders lived longer than patients with stable disease or progressive disease. CONCLUSIONS: Radiographic response to LRTs predicts survival time. EASL criteria for response more consistently predicted survival times than WHO criteria. The goal of LRT should be to achieve a radiologic response, rather than to stabilize disease.