Saffire S. K. S. Phoa

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 adenocarcinoma.

Diagnostic Accuracy of MRI in Differentiating Hepatocellular Adenoma From Focal Nodular Hyperplasia: Prospective Study of the Additional Value of Gadoxetate Disodium

OBJECTIVE The purpose of this article is to prospectively determine the sensitivity of hepatobiliary phase gadoxetate disodium-enhanced MRI combined with standard MRI in differentiating focal nodular hyperplasia (FNH) from hepatocellular adenoma (HCA). SUBJECTS AND METHODS Patients suspected of having FNH or HCA larger than 2 cm underwent gadoxetate disodium-enhanced MRI. Standard MRI was evaluated separately from the additional hepatobiliary phase by two blinded radiologists. For the largest lesion in each patient, findings were compared with histologic diagnosis. Sensitivity, positive predictive value (PPV), and distinctive features were analyzed using McNemar and analysis of variance tests. RESULTS Fifty-two patients completed the study. Histologic diagnosis revealed 24 HCAs and 28 FNHs. Characterization on standard MRI was inconclusive in 40% (21/52) and conclusive in 60% (31/52) of lesions. The sensitivity of standard MRI for HCA was 50% (12/24) with a PPV of 100% (12/12). The sensitivity for FNH was 68% (19/28) with a PPV of 95% (18/19). After review of hepatobiliary phase, the sensitivity for HCA improved to 96% (23/24) with a PPV of 96% (23/24). The sensitivity for FNH improved to 96% (27/28) with a PPV of 96% (27/28). Features with significant predictive value for diagnosis in HCA included bleeding (p < 0.001), fat (p = 0.010), and glycogen (p = 0.024). The presence of a central scar was predictive for FNH (p < 0.001). CONCLUSION This study shows high sensitivity of gadoxetate disodium-enhanced MRI when standard series are combined with the hepatobiliary phase for differentiation of FNH and HCA in lesions larger than 2 cm.

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 PC.

Follow-up of renal masses after cryosurgery using computed tomography; enhancement patterns and cryolesion size

To describe the characteristics of cryolesions as seen on computed tomography (CT), for size and enhancement patterns, and to assess correlations between these imaging findings and histopathological diagnosis, as in renal cryosurgery the tumour is ablated in situ and the follow‐up is mainly based on imaging.

Risk factors for bleeding in hepatocellular adenoma.

Hepatocellular adenoma (HCA) is a benign hepatic lesion that may be complicated by bleeding, although the risk of bleeding is ill‐defined. The aim of this study was to assess risk factors for bleeding in patients diagnosed with HCA.

Accuracy of MRI compared with ultrasound imaging and selective use of CT to discriminate simple from perforated appendicitis.

Discrimination between simple and perforated appendicitis in patients with suspected appendicitis may help to determine the therapy, timing of surgery and risk of complications. The aim of this study was to estimate the accuracy of magnetic resonance imaging (MRI) in distinguishing between simple and perforated appendicitis, and to compare MRI against ultrasound imaging with selected additional (conditional) use of computed tomography (CT).

Primary sclerosing cholangitis: sonographic findings

Background:To determine the value of sonography of the upper abdomen in primary sclerosing cholangitis (PSC).Methods:In a prospective study of 23 patients with PSC we performed upper abdominal sonography. Sonographic findings of the bile ducts were correlated with endoscopic retrograde cholangiographic (ERC) findings. Signs of advanced disease and complications were also sought.Results:The major limitation of ultrasound was its inability to exclude intrahepatic duct disease. In six patients with multiple strictures and pruning but without dilatations on ERC, sonography showed no intrahepatic duct abnormalities. Extrahepatic duct disease was adequately demonstrated on ultrasound. Mural thickening of the common bile duct (CBD), the hallmark of PSC in the appropriate clinical setting, was demonstrated in 17 of 18 cases with a stenosis on ERC. Ultrasound confirmed advanced disease manifested by signs of portal hypertension in seven patients. Marked nonsegmental intrahepatic duct dilatation and the presence of a mass lesion occurred in two of three cases in which complicating cholangiocarcinoma was found.Conclusion:Despite its inability to exclude intrahepatic duct disease, sonography is useful in diagnosing and following PSC.

Accuracy and reproducibility of 3D-CT measurements for early response assessment of chemoradiotherapy in patients with oesophageal cancer.

BACKGROUND Chemoradiotherapy is increasingly applied in patients with oesophageal cancer. The aim of the present study was to determine whether 3D-CT volumetry is able to differentiate between responding and non-responding oesophageal tumours early in the course of neoadjuvant chemoradiotherapy. PATIENTS AND METHODS Serial CT before and after two weeks of neoadjuvant chemoradiotherapy was performed in the multimodality treatment arm of a randomised trial including patients with oesophageal carcinoma. CT response was measured with the change in tumour volume between baseline and after 14 days of neoadjuvant therapy. Receiver Operating Characteristic (ROC) analysis was used to evaluate the ability of 3D-CT as an early imaging marker of response. RESULTS CT response analysis was performed in 39 patients, of whom 26 patients were histopathological responders. Median tumour volume increased between baseline and after 14 days of chemoradiotherapy in histopathological responders as well as in non-responders, though changes were not statistically significant. The area under the ROC curve was 0.71. CONCLUSION Tumour volume changes after 14 days of neoadjuvant chemoradiotherapy as measured by 3D-CT were not associated with histopathological tumour response. CT volumetry should not be used for early response assessment in patients with potentially curable oesophageal cancer treated with neoadjuvant chemoradiotherapy.

Diagnostic accuracy of 18F‐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 18F‐fluorocholine (18F‐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 18F‐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 18F‐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, McNemars test, and Kaplan‐Meiers test at 5% level of significance. Twenty‐nine patients revealed 53 intrahepatic lesions. In 48 of 53 lesions, 18F‐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 18F‐FCH PET/CT for patients with HCC. 18F‐FCH PET/CT has implications for staging, management, and treatment evaluation because of accurate assessment of extrahepatic disease. (Hepatology 2014;59:996–1006)

Additional Value of External Ultrasonography of the Neck after CT and PET Scanning in the Preoperative Assessment of Patients with Esophageal Cancer

Introduction: Lymphatic dissemination of a (non-cervical) esophageal tumor to the neck is generally considered as distant metastasis. The aim of this study was to determine the additional value of external ultrasonography (US) to detect lymphatic metastasis to the neck after normal CT scan (CT) with or without normal PET scan (PET). Methods: Between January 2003 and December 2005, 306 patients were analyzed for esophageal cancer in our department. A total of 233 patients underwent both CT and external US of the neck. PET was performed in 109 of these patients as part of a prospective cohort study. Fine needle aspiration (FNA) was only performed if external US reported suspected lymph nodes. FNA was defined as gold standard. Results: In 176 patients (76%), CT did not identify any suspected nodes, but external US disagreed in 36 of them. In 9 of these patients, FNA confirmed metastasis, resulting in an additional value of external US after normal CT scanning of 5% (9/176). In 74 patients (68%), CT and PET did not identify any suspected nodes, but external US disagreed in 11 of them. In 3 of these patients, FNA confirmed metastasis, resulting in an additional value of external US after normal CT and PET of 4% (3/74). Conclusion: Considering its minimal invasiveness and wide availability in combination with the importance of the potential therapeutic consequences, we conclude that external US of the neck should be part of the routine diagnostic work-up in patients with esophageal cancer, even after normal CT and PET scanning.