Vahid Yaghmai

Radioembolization results in longer time-to-progression and reduced toxicity compared with chemoembolization in patients with hepatocellular carcinoma

BACKGROUND & AIMS Chemoembolization is one of several standards of care treatment for hepatocellular carcinoma (HCC). Radioembolization with Yttrium-90 microspheres is a novel, transarterial approach to radiation therapy. We performed a comparative effectiveness analysis of these therapies in patients with HCC. METHODS We collected data from 463 patients who were treated with transarterial locoregional therapies (chemoembolization or radioembolization) over a 9-year period. We excluded patients who were not appropriate for comparison and analyzed data from 245 (122 who received chemoembolization and 123 who received radioembolization). Patients were followed for signs of toxicity; all underwent imaging analysis at baseline and follow-up time points. Overall survival was the primary outcome measure. Secondary outcomes included safety, response rate, and time-to-progression. Uni- and multivariate analyses were performed. RESULTS Abdominal pain and increased transaminase activity were more frequent following chemoembolization (P < .05). There was a trend that patients treated with radioembolization had a higher response rate than with chemoembolization (49% vs 36%, respectively, P = .104). Although time-to-progression was longer following radioembolization than chemoembolization (13.3 months vs 8.4 months, respectively, P = .046), median survival times were not statistically different (20.5 months vs 17.4 months, respectively, P = .232). Among patients with intermediate-stage disease, survival was similar between groups that received chemoembolization (17.5 months) and radioembolization (17.2 months, P = .42). CONCLUSIONS Patients with HCC treated by chemoembolization or radioembolization with Yttrium-90 microspheres had similar survival times. Radioembolization resulted in longer time-to-progression and less toxicity than chemoembolization. Post hoc analyses of sample size indicated that a randomized study with > 1000 patients would be required to establish equivalence of survival times between patients treated with these two therapies.

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.

Multimodality Imaging Following 90Y Radioembolization: A Comprehensive Review and Pictorial Essay

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

Imaging benign and malignant disease of the gallbladder

This article reviews the imaging of various benign and malignant diseases of the gallbladder. Clinical findings and imaging features using ultrasound, CT, and MR for the detection and evaluation of gallstones, acute cholecystitis, xanthogranulomatous cholecystitis, adenomyomatosis, and carcinoma of the gallbladder among other disorders are discussed.

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.

Diffusion-weighted MR imaging in pancreatic endocrine tumors correlated with histopathologic characteristics

To retrospectively assess apparent diffusion coefficients (ADCs) of different subtypes of pancreatic endocrine tumors based on the World Health Organization (WHO) classification system and analyze the potentially responsible histopathologic characteristics.

ACR appropriateness Criteria® right lower quadrant pain - Suspected appendicitis

The most common cause of acute right lower quadrant (RLQ) pain requiring surgery is acute appendicitis (AA). This narratives focus is on imaging procedures in the diagnosis of AA, with consideration of other diseases causing RLQ pain. In general, Computed Tomography (CT) is the most accurate imaging study for evaluating suspected AA and alternative etiologies of RLQ pain. Data favor intravenous contrast use for CT, but the need for enteric contrast when intravenous contrast is used is not strongly favored. Radiation exposure concerns from CT have led to increased investigation in minimizing CT radiation dose while maintaining diagnostic accuracy and in using algorithms with ultrasound as a first imaging examination followed by CT in inconclusive cases. In children, ultrasound is the preferred initial examination, as it is nearly as accurate as CT for the diagnosis of AA in this population and without ionizing radiation exposure. In pregnant women, ultrasound is preferred initially with MRI as a second imaging examination in inconclusive cases, which is the majority.The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every three years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

Diffusion-weighted magnetic resonance imaging of pancreatic adenocarcinomas: association with histopathology and tumor grade.

To evaluate the utility of diffusion‐weighted magnetic resonance imaging (DWI) in pancreatic ductal adenocarcinoma with various grades of differentiation.

Utility of Diffusion-Weighted MRI in Characterization of Adrenal Lesions

OBJECTIVE The purpose of our study was to evaluate the utility of apparent diffusion coefficient (ADC) values for characterizing adrenal lesions and determine if diffusion-weighted imaging (DWI) can distinguish lipid-rich from lipid-poor adenomas. MATERIALS AND METHODS We retrospectively evaluated 160 adrenal lesions in 156 patients (96 women and 60 men; mean age, 63 years). ADCs and signal intensity (SI) decrease on chemical shift imaging were measured in adrenal lesions with a wide variety of pathologies. Lipid-rich and lipid-poor adenomas were identified by unenhanced CT. The overall predictive power of ADC, SI decrease, and lesion size were determined by receiver operating characteristic (ROC) analysis. Areas under the ROC curve (AUC) were compared for equivalence using nonparametric methods. Sensitivity, specificity, and positive and negative predictive values were calculated. Correlation coefficients were used to assess ADCs versus percentage SI decrease and ADCs versus CT attenuation. RESULTS ADCs of adrenal malignancies (median, 1.67 x 10(-3) mm(2)/s; interquartile range, 1.41-1.84 x 10(-3) mm(2)/s) were not different compared with those of benign lesions (1.61 x 10(-3) mm(2)/s; 1.27-1.96 x 10(-3) mm(2)/s; p > 0.05). Cysts (2.93 x 10(-3) mm(2)/s; 2.70-3.09 x 10(-3) mm(2)/s) showed higher ADCs than the remaining adrenal lesions (p < 0.05). The median ADCs of lipid-rich adenomas did not differ from those of lipid-poor ones (p > 0.05). The CT attenuation had no negative or positive correlation with the ADCs of adrenal adenomas (r = -0.05, p = 0.97). CONCLUSION Unlike lesion size and percentage decrease in SI, the ADCs were not useful in distinguishing benign from malignant adrenal lesions. Lipid-poor adenomas could not be distinguished from lipid-rich adenomas and all other nonfatty lesions of the adrenal gland with DWI.

Radiological-pathological analysis of WHO, RECIST, EASL, mRECIST and DWI: Imaging analysis from a prospective randomized trial of Y90 ± sorafenib

The aim of this study was to compare radiological and pathological changes and test the adjunct efficacy of Sorafenib to Y90 as a bridge to transplantation in hepatocellular carcinoma (HCC). 15 patients with 16 HCC lesions were randomized to Y90 without (Group A, n = 9) or with Sorafenib (Group B, n = 7). Size (WHO, RECIST), enhancement (EASL, mRECIST) and diffusion‐weighted imaging criteria (apparent diffusion coefficient, ADC) measurements were obtained at baseline, then at 1 and every 3 months after treatment until transplantation. Percentage necrosis in explanted tumors was correlated with imaging findings. 100%, 50%‐99% and <50% pathological necrosis was observed in 6 (67%), 1 (11%), and 2 (22%) tumors in Group A and 3 (42%), 2 (28%), and 2 (28%) in Group B, respectively (P = 0.81). While ADC (P = 0.46) did not change after treatment, WHO (P = 0.06) and RECIST (P = 0.08) response at 1 month failed to reach significance, but significant responses by EASL (P < 0.01/0.03) and mRECIST (P < 0.01/0.03) at 1 and 3 months were observed. Response was equivalent by EASL or mRECIST. No difference in response rates was observed between groups A and B at 1 and 3 months by WHO, RECIST, EASL, mRECIST or ADC measurements. Despite failing to reach significance, smaller baseline size was associated with complete pathological necrosis (CPN) (RECIST: P = 0.07; WHO: P = 0.05). However, a cut‐off size of 35 mm was predictive of CPN (P = 0.005). CPN could not be predicted by WHO (P = 0.25 and 0.62), RECIST (P = 0.35 and 0.54), EASL (P = 0.49 and 0.46), mRECIST (P = 0.49 and 0.60) or ADC (P = 0.86 and 0.93). Conclusion: The adjunct of Sorafenib did not augment radiological or pathological response to Y90 therapy for HCC. Equivalent significant reduction in enhancement at 1 and 3 months by EASL/mRECIST was noted. Neither EASL nor mRECIST could reliably predict CPN. (HEPATOLOGY 2013;58:1655–1666)