Imaging Modalities for Focal Nodular Hyperplasia and Hepatocellular Adenoma

Background/Aims: There are several imaging modalities available for the detection of focal liver lesions. Differentiation between focal nodular hyperplasia (FNH) and hepatocellular adenoma (HCA) is important because of the consequences for management. However, differentiation based on imaging alone still shows limitations. Methods: We reviewed the literature for typical features of FNH and HCA on radiologic and nuclear imaging with emphasis on differentiation of both lesions. Results: Seven articles describe the performance of an imaging modality for the differentiation between FNH and HCA. Limitations of these studies are the small sample size and/or the lack of comparison with the 'gold standard', i.e. histological diagnosis. No studies are available that compare the accuracy of several imaging modalities in the differentiation of FNH and HCA. Conventional ultrasound (US) is not useful in the differentiation because of the non-specific features. On contrast-enhanced US, the arterial filling direction of FNH is centrifugal and centripetal in case of HCA. The parenchymal enhancement of FNH is sustained in the portal venous and delayed phases, but shows rapid washout in case of HCA. Multiphase CT scan can differentiate FNH from HCA when there is a central scar. FNH may have a slightly higher relative enhancement in the arterial phase. On MRI with hepatocyte-specific contrast agents, HCA does not show contrast uptake in the hepatobiliary phase in contrast to FNH. Conclusion: We conclude that there is limited evidence of the diagnostic performance of currently used imaging modalities for the differentiation of FNH and HCA. We therefore propose a prospective study (DiFA trial) to determine the accuracy of several radiologic and nuclear imaging studies in differentiating FNH and HCA. Copyright (C) 2010 S. Karger AG, Base

Diagnostic Accuracy of (18) F-Methylcholine Positron Emission Tomography/Computed Tomography for Intra- and Extrahepatic Hepatocellular Carcinoma

Diagnosis of hepatocellular carcinoma (HCC) primarily involves imaging. The aim of this study was to assess the accuracy of F-18-fluorocholine (F-18-FCH) positron emission tomography (PET) for detection of HCC and evaluation of extent of disease. Patients with HCC >1 cm were included between 2009 and July 2011, and follow-up closed in February 2013. Diagnosis was based on American Association for the Study of Liver Diseases criteria, and all patients underwent F-18-FCH PET/computed tomography (CT) at baseline before treatment, 6 underwent a second PET/CT posttreatment, and 1 a third during follow-up. Whole-body PET and low-dose CT imaging were performed 15 minutes after F-18-FCH injection. Evaluation of imaging was done with standardized uptake value (SUV) ratios: SUV maximum of the lesion divided by the SUV mean of surrounding tissue. Statistical analyses included descriptive analyses, receiver operating characteristic curve, McNemar's test, and Kaplan-Meier's test at 5% level of significance. Twenty-nine patients revealed 53 intrahepatic lesions. In 48 of 53 lesions, F-18-FCH PET was positive (SUVratio, 1.95 +/- 0.66; sensitivity, 88%; specificity, 100%). PET/CT showed uptake in 18 extrahepatic lesions and no uptake in 3 lesions affirmed non-HCC lesions; all lesions were confirmed with additional investigation (accuracy, 100%). In 17 of 29 patients, additional lesions were found on PET/CT imaging, with implications for treatment in 15 patients. Posttreatment PET/CT showed identical results, compared with standard treatment evaluation. Conclusion: This study shows additional value of F-18-FCH PET/CT for patients with HCC. F-18-FCH PET/CT has implications for staging, management, and treatment evaluation because of accurate assessment of extrahepatic disease. (Hepatology 2014;59:996-1006

The use of 18F-fluoromethylcholine PET/CT in differentiating focal nodular hyperplasia from hepatocellular adenoma: a prospective study of diagnostic accuracy

Diagnosis of focal nodular hyperplasia (FNH) and hepatocellular adenoma (HCA) using conventional imaging techniques can be difficult; however, it is important to differentiate between them as these benign liver tumors require different therapeutic strategies. The aim of our study was to prospectively evaluate the use of PET/computed tomography (CT) with F-fluoromethylcholine (F-FCH) as a novel diagnostic approach in the differentiation between HCA and FNH. Fifty-six consecutive patients with a suspicion of one or multiple HCAs or FNHs larger than 2 cm were prospectively included after written informed consent was obtained from them. All the patients underwent a PET/CT with F-FCH. Histopathology of the lesions was the standard of reference. The ratio of the standardized uptake value (SUV) of the lesions compared with normal liver uptake within the same patient was calculated. Statistical tests were evaluated at the 95% confidence interval. Forty-nine patients with 60 lesions and histopathological diagnosis of FNH or HCA completed the study and were analyzed. The mean SUV ratio for FNH was 1.67±0.31 (mean±SD, n=28), resulting in a positive likelihood ratio of 32.3 for PET-positive FNH. The mean SUV ratio for HCA was 0.82±0.17 (n=32), with a likelihood ratio of ∼100 for PET-negative HCA. Receiver operating characteristic curve analysis revealed an optimal SUV ratio cutoff value of 1.13, which reached 100% sensitivity and 97% specificity in differentiating FNH from HCA. This prospective study shows that PET/CT with F-FCH can accurately differentiate FNH from HCA and may become a valuable diagnostic tool when conventional imaging techniques fail to do s

Two Cases of Hepatoblastoma in Young Adults

Adult hepatoblastoma (AHB) is a rare liver tumor with a poor prognosis in adolescents and adults. This contrasts with hepatoblastoma in children and is not fully understood. Here we describe two adolescents with AHB who were treated in our hospital. Adolescents are likely to receive less intensive chemotherapy protocols and are treated in hospitals with less experience in pediatric oncology, resulting in poor outcome. More research is necessary for optimal treatment of AHB in adolescents. Adolescents with AHB should be referred to hospitals experienced in pediatric oncology and receive intensive chemotherapy, followed by hemihepatectomy

Outcomes of liver resection in hepatocellular adenoma and focal nodular hyperplasia

The clinical management of hepatocellular adenoma (HCA) and focal nodular hyperplasia (FNH) is still subject to controversy, especially with respect to patient selection for surgery. The aim of this prospective cohort study was to assess the outcomes of surgical intervention. Between January 2008 and September 2012, patients diagnosed with FNH or HCA based on magnetic resonance imaging or computed tomography were enrolled in this prospective study. Resection was undertaken in patients with HCA of > 5 cm or symptomatic lesions. Lesion characteristics, extent of liver resection (minor: fewer than three segments; major: three or more segments), morbidity (by Dindo-Clavien class), mortality, postoperative length of stay and symptoms [McGill Pain Questionnaire, including a visual analogue scale (VAS)] were evaluated. A total of 110 patients (106 female; median age: 39 years) were included; 51 patients had HCA and 59 had FNH. Of the 110 patients, 49 underwent resection (33 HCA patients; 16 FNH patients). Laparoscopic minor resection was performed in five HCA and five FNH patients; open minor resection was performed in 19 HCA and seven FNH patients, and open major resection was performed in nine HCA and four FNH patients. Severe postoperative complications were observed in four patients (Grade III, n = 3; Grade IV, n = 1). Median baseline scores on the VAS were 6 in FNH patients and 7 in HCA patients; the median VAS score after resection was 0 (P = 0.008). If patients with HCA and FNH require surgery, limited resection can be carried out with low morbidity and without mortality. Patients with preoperative symptoms show a high rate of postoperative symptom relie

Ultrasonography, computed tomography and magnetic resonance imaging for diagnosis and determining resectability of pancreatic adenocarcinoma - A meta-analysis

Objective: To compare ultrasonography (US), computed tomography (CT), and magnetic resonance imaging (MRI) in the diagnosis and determination of resectability of pancreatic adenocarcinoma. Methods: Articles reporting US, CT, or MRI data of patients with known or suspected pancreatic adenocarcinoma and at least 20 patients verified with histopathology, surgical findings, or follow-up were included. A bivariate random effects approach was used to calculate sensitivity and specificity for diagnosis and resectability of pancreatic adenocarcinoma. Results: Sixty-eight articles fulfilled all inclusion criteria. For diagnosis, sensitivities of helical CT, conventional CT, MRI, and US were 91%, 86%, 84%, and 76% and specificities were 85%, 79%, 82%, and 75% respectively. Sensitivities for MRI and US were significantly lower compared with helical CT (P = 0.04 and P = 0.0001). For determining resectability, sensitivities of helical CT, conventional CT, MRI, and US were 81%, 82%, 82, and 83% and specificities were 82%, 76%, 78%, and 63% respectively. Specificity of US was significantly lower compared with helical CT (P = 0.011). Conclusions: Helical CT is preferable as an imaging modality for the diagnosis and determination of resectability of pancreatic adenocarcinom

Value of CT criteria in predicting survival in patients with potentially resectable pancreatic head carcinoma

Background and Objective: Survival is often poor after resection of pancreatic tumors. We correlated the pre-operative CTs with survival to find criteria that have prognostic value. To establish the prognostic value of CT in patients with potentially resectable pancreatic head carcinoma. Methods: In 71 consecutive patients with potentially resectable pancreatic head carcinoma, prognostic factors on CT were scored, for example, tumor size, peripancreatic infiltration, grades of vascular encasement, and local irresectability. All patients underwent surgical exploration. CT findings were compared with results of surgery and histopathology. Prognostic factors for resected and unresected tumors were analyzed using single and multivariate analysis Results: Forty-one of 71 tumors were resected (24 radical). The sensitivity, specificity, and positive predictive value of CT for surgical irresectability were 0.67, 0.63, and 0.57, respectively. For a non-radical resection, these were 0.62, 0.75, and 0.83, respectively. The median survival was 21 months for resemble tumors and 9.7 months for unresectable tumors. For resected tumors, a tumor diameter of >3 cm (relative hazard 3.8) and CT signs of local unresectability showed a poor survival. The median survival of resected tumors 3 cm predict a poor survival after resectio

Computed tomographic findings characteristic for encapsulating peritoneal sclerosis: a case-control study

BACKGROUND: Computed tomography (CT) is often used to confirm the diagnosis of encapsulating peritoneal sclerosis (EPS) but there is no consensus on specific CT abnormalities. To establish CT findings characteristic for EPS, we compared CT findings between EPS patients and long-term peritoneal dialysis (PD) patients without EPS. METHODS: We included as cases all EPS patients in our center from 1996 to 2008 that underwent a CT scan at the time of diagnosis. Controls were all other long-term PD patients (PD duration > or = 4 years) without EPS that had a CT scan for different reasons. The CT scans were blindly and independently reviewed by 3 radiologists: 2 abdominal radiologists with PD knowledge (Observers 1 and 2) and 1 radiologist without PD experience (Observer 3). RESULTS: We included 15 EPS patients and 16 controls. Observer 1 found 6 CT findings that were significantly more often present in EPS than in controls (p < or = 0.05): peritoneal enhancement, thickening, and calcifications; adhesions of bowel loops; signs of obstruction; and fluid loculation/septation. Observer 2 scored almost identically but Observer 3 scored differently. The sensitivity and specificity of a combination of specific CT findings were, respectively, 100% and 94% for Observers 1 and 2, and 79% and 88% for Observer 3. CONCLUSION: CT scans showed characteristic abnormalities that were significantly more often present in EPS patients compared to long-term PD control patients. CT can be used to confirm the diagnosis of EPS when experienced radiologists apply a combination of specific CT finding

Disappointing Interobserver Agreement Among Radiologists for a Classifying Diagnosis of Pancreatic Cysts Using Magnetic Resonance Imaging

Objectives: To assess the degree of interobserver agreement of MRI in the diagnostic assessment of pancreatic cysts (PCs). Methods: Magnetic resonance imaging sets of images of 62 patients with PCs (32 with histological confirmation and 30 with clinical diagnosis) were reviewed by 4 experienced radiologists. Features scored included septations, nodules, solid components, pancreatic duct communication, and wall thickening (>2 mm). Radiologists were asked whether they considered the PC mucinous and if the PC was suspicious for malignancy. Furthermore, they had to choose a classifying diagnosis. Intraclass correlation coefficient (ICC) was used to measure agreement within the group. Results: Interobserver agreement for septations and nodules was fair (ICC, 0.36 and 0.23, respectively). Agreement for the presence of solid components was fair (ICC, 0.23), agreement for communication with the pancreatic duct was moderate (ICC, 0.53), and agreement for wall thickening was moderate (ICC, 0.44). There was fair agreement for the discrimination between mucinous and nonmucinous PC (ICC, 0.36). Agreement was fair (ICC, 0.26) for a classifying diagnosis and fair for the presence of malignant features (ICC, 0.33). Conclusions: Interobserver agreement was poor to moderate for individual PC features, and there was fair agreement for a classifying diagnosis. Magnetic resonance imaging morphology alone did not allow for a reliable discrimination between different types of P