First-Rib Stress Fracture in Overhead Throwing Athletes.

BACKGROUND: First-rib stress fracture is considered a potential cause of nonspecific atraumatic chronic shoulder pain in adolescent athletes. However, the etiology in throwing athletes with first-rib fracture is still unknown. The purpose of this retrospective study was to investigate the characteristic clinical features and radiographic findings of overhead throwing athletes with first-rib fracture. METHODS: Twenty-four first-rib stress fractures in 23 players were studied retrospectively. Clinical features, including age, initial symptom, sports, pain-related activity, diagnostic method, treatment method, and final follow-up, were reviewed. RESULTS: The following characteristic clinical features were identified: mean age of 16.8 years (range, 13 to 25 years), 19 dominant arm injuries and 5 non-dominant arm injuries, and an acute increase in pain while swinging the bat or pitching the ball. Sixteen fractures presented with posterior shoulder or upper thoracic back pain. At a mean time of 7.5 months after the initiation of conservative treatment, 17 healing fractures (71%) and 7 nonunion fractures (29%) among throwing athletes with first-rib stress fracture were identified. On image analysis, first-rib stress fractures were classified into 3 types depending on the direction and location of fracture lines: groove, intrascalene, and posterior types. Three symptomatic patients underwent first-rib resection due to thoracic outlet syndrome. On average, 46% of the first rib was visible on the shoulder radiographs and 97% was visible on the cervical spine radiographs. The Cohen kappa coefficient for the above percentages was 0.87 and the percent agreement was 89.4% for the shoulder, and the Cohen kappa coefficient was 0.80 and the percent agreement was 99.0% for the cervical spine. CONCLUSIONS: First-rib stress fracture should be considered when adolescent overhead throwing athletes have acute-onset posterior shoulder pain while swinging the bat or pitching the ball. Anteroposterior radiography of the cervical spine is available for initial diagnosis. Although 71% of the patients healed at a mean follow-up of 7.5 months with conservative treatment, some patients may have symptoms consistent with thoracic outlet syndrome. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

JSUM ultrasound elastography practice guidelines: pancreas.

Ultrasound elastography is a relatively new diagnostic technique for measuring the elasticity (hardness) of tissue. Eleven years have passed since the debut of elastography. Various elastography devices are currently being marketed by manufacturers under different names. Pancreatic elastography can be used not only with transabdominal ultrasonography but also with endoscopic ultrasonography, but some types of elastography are difficult to perform for the pancreas. These guidelines aim to classify the various types of elastography into two major categories depending on the differences in the physical quantity (strain, shear wave), and to present the evidence for pancreatic elastography and how to use pancreatic elastography in the present day. But the number of reports on ultrasound elastography for the pancreas is still small, and there are no reports on some elastography devices for the pancreas. Therefore, these guidelines do not recommend methods of imaging and analysis by elastography device.

Investigation of Morphological and Functional Changes in the Small Intestine With Pancreatic Disease.

OBJECTIVES: The aim of this study was to investigate the relationship between pancreas and small intestine evaluating the endoscopic and histopathologic findings of the proximal small intestine in pancreatic diseases. METHODS: Fifty patients (18 patients with chronic pancreatitis, 17 patients with pancreatic cancer, 15 control subjects) underwent enteroscopy using a prototype enteroscope. The villous height of the jejunum on bioptic specimens was measured, and the mean values of the villi were compared among the 3 groups. Exocrine function was calculated by the pancreatic function diagnostic test, and the correlation between the recovery rate of p-aminobenzoic acid and the villous height was assessed. Finally, the distribution of the K cells secreting glucose-dependent insulinotropic polypeptide and the L cells secreting glucagon-like peptide 1 in the duodenum and jejunum was investigated using immunohistochemistry for glucose-dependent insulinotropic polypeptide and glucagon-like peptide 1. RESULTS: The mean villous height in chronic pancreatitis (328 ± 67 µm) was significantly lower than that in pancreatic cancer (413 ± 57 µm) and control subjects (461 ± 97 µm) (P = 0.004 and P < 0.0001, respectively). A positive correlation was found between the recovery rate of p-aminobenzoic acid and the villous height (r = 0.52, P = 0.0001). The presence of K and L cells was verified in the duodenum and the jejunum. CONCLUSIONS: Close relationship between pancreas and small intestine was demonstrated.

Usefulness and safety of endoscopic retrograde cholangiopancreatography in children with pancreaticobiliary maljunction.

BACKGROUND: To assess the diagnostic ability and safety of endoscopic retrograde cholangiopancreatography (ERCP) in in-depth preoperative examination of children patients with pancreaticobiliary maljunction (PBM). METHODS: In 63 patients with a definite diagnosis of PBM, the ability to visualize the bile and main pancreatic ducts was compared between ERCP, which was performed in 63 patients with a definite diagnosis of PBM, and magnetic resonance cholangiopancreatography (MRCP), which was performed before ERCP in 29 patients. For ERCP, its complications were also evaluated. RESULTS: The intrahepatic bile ducts could be visualized using ERCP in 44 patients (69.8%) and using MRCP in 18 (62.1%). The extrahepatic bile ducts could be visualized using ERCP in 59 patients (93.7%) and using MRCP in 29 (100%). The rates of the visualization of the main pancreatic duct and pancreaticobiliary ductal union were significantly higher in using ERCP than in using MRCP (96.8 vs. 41.4% and 90.5 vs. 37.9%, respectively; P<0.0001). As complications, hyperamylasemia developed in 12 patients (19%), but no other severe complications such as pancreatitis were observed. CONCLUSIONS: ERCP as part of an in-depth preoperative examination of children with PBM is useful and safe.

[Subcutaneous continuous injection of octreotide decreased the tumor marker levels and induced cystic necrosis of the tumors in a case of pancreatic neuroendocrine tumor with multiple hepatic metastases].

For symptom alleviation, subcutaneous continuous injection of octreotide was administered to a patient with pancreatic neuroendocrine tumor (NET) accompanied by multiple hepatic metastases and ascites. The level of the tumor marker neuron-specific enolase decreased to the normal range and cystic necrosis of the tumors was confirmed. There have been some reports on the antineoplastic effects of octreotide on pancreatic NET; therefore, octreotide appears to be a valid option as a therapeutic agent in patients with highly advanced pancreatic NET, in whom administration of molecular targeted or anticancer agents is difficult because of a poor general status.

Preliminary study on evaluation of the pancreatic tail observable limit of transabdominal ultrasonography using a position sensor and CT-fusion image.

BACKGROUND AND AIM: Transabdominal ultrasonography (US) is commonly used for the initial screening of bilio-pancreatic diseases in Asian countries due to its widespread availability, the non-invasiveness and the cost-effectiveness. However, it is considered that US has limits to observe the area, namely the blind area. The observation of the pancreatic tail is particularly difficult. The goal of this study was to examine the pancreatic tail region that cannot be visualized on transverse scanning of the upper abdomen using US with spatial positional information and factors related to visualization, and observation of the tail from the splenic hilum. METHODS: Thirty-nine patients with pancreatic/biliary tract disease underwent CT and US with GPS-like technology and fusion imaging for measurement of the real pancreatic length and the predicted/real unobservable (PU and RU) length of the pancreatic tail. RU from US on transverse scanning and the real pancreatic length were used to determine the unobservable area (UA: RU/the real pancreatic length). Relationships of RU with physical and hematological variables that might influence visualization of the pancreatic tail were investigated. RESULTS: The real pancreatic length was 160.9 ± 16.4mm, RU was 41.0 ± 17.8mm, and UA was 25.3 ± 10.4%. RU was correlated with BMI (R=0.446, P=0.004) and waist circumferences (R=0.354, P=0.027), and strongly correlated with PU (R=0.788, P<0.001). The pancreatic tail was visible from the splenic hilum in 22 (56%) subjects and was completely identified in 13 (33%) subjects. CONCLUSIONS: Combined GPS-like technology with fusion imaging was useful for the objective estimation of the pancreatic blind area.

Quantitative analysis of diagnosing pancreatic fibrosis using EUS-elastography (comparison with surgical specimens).

BACKGROUND: An accurate diagnosis of pancreatic fibrosis is clinically important and may have potential for staging chronic pancreatitis. The aim of this study was to diagnose the grade of pancreatic fibrosis through a quantitative analysis of endoscopic ultrasound elastography (EUS-EG). METHODS: From September 2004 to October 2010, 58 consecutive patients examined by EUS-EG for both pancreatic tumors and their upstream pancreas before pancreatectomy were enrolled. Preoperative EUS-EG images in the upstream pancreas were statistically quantified, and the results were retrospectively compared with postoperative histological fibrosis in the same area. For the quantification of EUS-EG images, 4 parameters (mean, standard deviation, skewness, and kurtosis) were calculated using novel software. Histological fibrosis was graded into 4 categories (normal, mild fibrosis, marked fibrosis, and severe fibrosis) according to a previously reported scoring system. RESULTS: The fibrosis grade in the upstream pancreas was normal in 24 patients, mild fibrosis in 19, marked fibrosis in 6, and severe fibrosis in 9. Fibrosis grade was significantly correlated with all 4 quantification parameters (mean r = -0.75, standard deviation r = -0.54, skewness r = 0.69, kurtosis r = 0.67). According to the receiver operating characteristic analysis, the mean was the most useful parameter for diagnosing pancreatic fibrosis. Using the mean, the area under the ROC curves for the diagnosis of mild or higher-grade fibrosis, marked or higher-grade fibrosis and severe fibrosis were 0.90, 0.90, and 0.90, respectively. CONCLUSIONS: An accurate diagnosis of pancreatic fibrosis may be possible by analyzing EUS-EG images.

Feasibility of newly developed endoscopic ultrasound with zone sonography technology for diagnosis of pancreatic diseases.

BACKGROUND/AIMS: To confirm the feasibility of using newly developed endoscopic ultrasound (EUS) with Zone sonography™ technology (ZST; Fujifilm Corp.). METHODS: Seventy-five patients with pancreatic disorders were enrolled: 45 with intraductal papillary mucinous neoplasm; 15 with ductal carcinoma; five with neuroendocrine tumors; three with serous cystic neoplasms; and seven with simple cysts. The endoscopes used were EG-530UR2 and EG-530UT2 (Fujifilm Corp.). Two items were evaluated: visualization depth among four frequencies and image quality after automatic adjustment of sound speed (AASS), assessed using a 5-scale Likert scale by two endosonographers blinded to disease status. Because sound speed could be manually controlled, besides AASS, image quality at sound speeds of 1,440 and 1,600 m/sec were also assessed. RESULTS: In all cases, sufficient images were obtained in the range of 3 cm from the EUS probe. Judgments of image quality before AASS were 3.49±0.50, 3.65±0.48, respectively. After AASS, A and B scored 4.36±0.48 and 4.40±0.49 (p<0.0001). There were significant differences in the data before and after AASS and plus 60 m/sec, but no significant difference between the datasets were seen after AASS and at sound speeds manually set for minus 100 m/sec. CONCLUSIONS: EUS with ZST was shown to be feasible in this preliminary experiment. Further evaluation of this novel technology is necessary and awaited.

Preoperative endoscopic nasobiliary drainage in 164 consecutive patients with suspected perihilar cholangiocarcinoma: a retrospective study of efficacy and risk factors related to complications.

OBJECTIVE: To assess the clinical benefits of preoperative endoscopic nasobiliary drainage (ENBD) in patients with perihilar cholangiocarcinoma. BACKGROUND: The advantages of ENBD have been previously reported. However, no studies to date have examined a large number of patients, including those with Bismuth-Corlette (B-C) type III to IV tumors. In addition, sufficient data on the risk factors associated with ENBD complications are not available. METHODS: This study involved 164 consecutive patients with suspected perihilar cholangiocarcinoma (128 patients with B-C type III-IV tumors) who had undergone unilateral ENBD between January 2007 and December 2010. The success and efficacy of this procedure and the risk factors for post-ENBD cholangitis and pancreatitis were retrospectively evaluated. RESULTS: The ENBD procedure was successful in 153 (93.3%) of the 164 patients. Of these 164 patients, 65 had serum total bilirubin (TB) levels of 2.0 mg/dL or more before the drainage. The first unilateral ENBD was successfully performed in 60 of the 65 patients, and the TB level decreased to less than 2.0 mg/dL after ENBD in 50 of these 60 patients (83.3%). The significant predictive factors for ENBD efficacy included the pre-ENBD TB level (P = 0.032; 95% confidence interval [CI], 1.01-1.23) and post-ENBD cholangitis (P = 0.012; 95% CI, 1.61-43.2). Post-ENBD cholangitis occurred in 47 (28.8%) of the 163 patients, and a previous endoscopic sphincterotomy (EST) was found to be a significant risk factor for post-ENBD cholangitis (P = 0.008; 95% CI, 1.30-5.46). Post-ENBD pancreatitis occurred in 33 (20.1%) of the 164 patients (26 grade 1 patients, 4 grade 2 patients, and 3 grade 3 patients). The significant risk factors included undergoing pancreatography (P < 0.001; 95% CI, 2.44-31.1) and the absence of previous EBS or ENBD (P < 0.001; 95% CI, 3.03-29.2). CONCLUSIONS: Unilateral ENBD of the future remnant lobe(s) exhibited a high success rate, suggesting that it is an effective and suitable preoperative drainage method for perihilar cholangiocarcinoma even in patients with B-C type III to IV tumors. To reduce the postprocedural complications, ENBD should be performed without EST or pancreatography.

Contrast-enhanced endoscopic ultrasonography in digestive diseases.

Contrast-enhanced endoscopic ultrasonography (CE-EUS) was introduced in the early 1990s. The concept of the injection of carbon dioxide microbubbles into the hepatic artery as a contrast material (enhanced ultrasonography) led to "endoscopic ultrasonographic angiography". After the arrival of the first-generation contrast agent, high-frequency (12 MHz) EUS brought about the enhancement of EUS images in the diagnosis of pancreatico-biliary diseases, upper gastrointestinal (GI) cancer, and submucosal tumors. The electronic scanning endosonoscope with both radial and linear probes enabled the use of high-end ultrasound machines and depicted the enhancement of both color/power Doppler flow-based imaging and harmonic-based imaging using second-generation contrast agents. Many reports have described the usefulness of the differential diagnosis of pancreatic diseases and other abdominal lesions. Quantitative evaluation of CE-EUS images was an objective method of diagnosis using the time-intensity curve (TIC), but it was limited to the region of interest. Recently developed Inflow Time Mapping™ can be generated from stored clips and used to display the pattern of signal enhancement with time after injection, offering temporal difference of contrast agents and improved tumor characterization. On the other hand, three-dimensional CE-EUS images added new information to the literature, but lacked positional information. Three-dimensional CE-EUS with accurate positional information is awaited. To date, most reports have been related to pancreatic lesions or lymph nodes. Hemodynamic analysis might be of use for diseases in other organs: upper GI cancer diagnosis, submucosal tumors, and biliary disorders, and it might also provide functional information. Studies of CE-EUS in diseases in many other organs will increase in the near future.

Peripancreatic vascular involvements of autoimmune pancreatitis.

BACKGROUND AND AIM: Although peripancreatic vascular lesions are occasionally encountered in autoimmune pancreatitis (AIP), there are few reports focusing on these involvements. We aimed to investigate the peripancreatic vascular involvements associated with AIP. METHODS: We retrospectively analyzed 54 AIP patients who met the International Consensus Diagnostic Criteria for AIP between July 2003 and October 2010. All of the 54 patients were subjected to multiphasic multidetector computed tomography, and the prevalence, location and prognosis of peripancreatic vascular involvements were investigated. RESULTS: Of the 54 AIP patients, 24 (44.4%) exhibited involvements in the form of peripancreatic vascular lesions (stenoses of the splenic vein in 22 and of the superior mesenteric-portal vein in 13, development of perigastric collateral circulation in 18, gastric varices with a red color sign in one and thrombosis inside the portal vein in one). Diffuse-type AIP was associated with a significantly higher prevalence of vascular involvements compared with focal-type AIP (P = 0.033). A total of 14 out of 16 patients who underwent corticosteroid treatment showed improvement in vascular lesions. One case followed up without corticosteroid treatment and presenting an obstruction of the splenic vein exhibited involvements in the form of an infarction and hemorrhagic cysts of the spleen and ultimately underwent distal pancreatectomy and splenectomy. CONCLUSIONS: Autoimmune pancreatitis patients show a high prevalence of peripancreatic vascular involvements. Thus, patients with vascular involvements are suitable candidates for steroid therapy with evaluation of its potential merits and demerits, even if they are asymptomatic.

Endoscopic ultrasound-guided fine needle aspiration in the differentiation of type 1 and type 2 autoimmune pancreatitis.

AIM: To investigate the usefulness of endoscopic ultra-sound-guided fine needle aspiration (EUS-FNA) in the differentiation of autoimmune pancreatitis (AIP). METHODS: We retrospectively reviewed 47 of 56 AIP patients who underwent EUS-FNA and met the Asian diagnostic criteria. On 47 EUS-FNA specimens, we evaluated the presence of adequate material and characteristic features of lymphoplasmacytic sclerosing pancreatitis (LPSP) and idiopathic duct-centric pancreatitis (IDCP) mentioned in the International Consensus Diagnostic Criteria and examined if these findings make a contribution to the differential diagnosis of type 1 and type 2 AIP. A disposable 22-gauge needle was used for EUS-FNA. RESULTS: Adequate specimens including pancreatic tissue for differentiating AIP from cancer were obtained from 43 of 47 patients who underwent EUS-FNA. EUS-FNA was performed from the pancreatic head in 21 cases, which is known to be technically difficult when performed by core biopsy; there was no significant difference in the results compared with pancreatic body-tail. Nine of 47 patients met level 1 findings of LPSP and 5 patients met level 2 findings of LPSP. No one met level 1 findings of IDCP, but 3 patients met level 2 findings of IDCP. Of 10 seronegative cases, 2 cases were diagnosed with "definitive type 1 AIP", and 3 cases were diagnosed with "probable type 2 AIP" when considering both the level 2 histological findings and response to steroids. CONCLUSION: EUS-FNA is useful in the differentiation of type 1 and type 2 AIP, particularly in seronegative cases.

Selective production of lactic acid in continuous anaerobic acidogenesis by extremely low pH operation.

The selective production of lactic acid by anaerobic acidogenesis with low pH control was examined using a chemostat culture. By decreasing culture pH to 3.5 in a chemostat culture containing mixed microbial populations for anaerobic acidogenesis, heterolactic fermentation became dominant, resulting in the selective production of lactic acid and ethanol. This phenomenon was reversible between the acidic and neutral conditions, and was not affected by the dilution rate. The extremely low pH operation was effective for selective lactic acid production in anaerobic acidogenesis.

Malignant transformation of branch duct-type intraductal papillary mucinous neoplasms of the pancreas based on contrast-enhanced endoscopic ultrasonography morphological changes: focus on malignant transformation of intraductal papillary mucinous neoplasm itself.

OBJECTIVES: The natural history of branch duct-type intraductal papillary mucinous neoplasms (BD-IPMNs) of the pancreas remains unclear. We conducted a retrospective long-term follow-up study for malignant transformation (MT) of BD-IPMNs focusing on morphological changes. METHODS: The subjects consisted of 142 patients who underwent contrast-enhanced endoscopic ultrasonography for initial diagnosis from January 2001 with more than 12 months of follow-up. The MT rate, including the co-occurrence of invasive ductal cancer, was evaluated by univariate and multivariate analysis. In addition, on the basis of morphological changes in patients who underwent surgery, the predictive factors for malignant IPMNs were evaluated. RESULTS: Median follow-up term was 42.5 months (range, 12-105 months). Thirty patients who exhibited morphological changes underwent surgery. Malignant transformation occurred in 9 patients (6.3%), and 5-year MT rate was 10.7%. The co-occurrence of invasive ductal cancer was seen in 5 patients. Multivariate analysis showed that the existence of mural nodules at initial diagnosis and involvement of main pancreatic duct were significant predictors of MT of BD-IPMN. CONCLUSIONS: Malignant transformation of BD-IPMN is not rare. The observation of morphological changes of main pancreatic duct and nodules, mainly on contrast-enhanced endoscopic ultrasonography, is practical and useful for predicting MT of BD-IPMN itself.

Dynamic quantitative evaluation of contrast-enhanced endoscopic ultrasonography in the diagnosis of pancreatic diseases.

OBJECTIVES: This study aimed to investigate the usefulness of contrast-enhanced endoscopic ultrasonography (EUS) with time-intensity curve (TIC) in differentiating pancreatic diseases. METHODS: Patients who underwent contrast-enhanced EUS between January 2007 and June 2009 were analyzed retrospectively, including 48 with pancreatic ductal cancer (PC), 14 with autoimmune pancreatitis (AIP), 13 with mass-forming pancreatitis (MFP), and 16 with pancreatic endocrine tumor (PET). After intravenous injection of contrast agent, contrast imaging pattern, TIC-based quantitative evaluation, and diagnostic ability of EUS in combination with TIC to diagnose benignancy or malignancy were assessed. RESULTS: Hypovascular and heterogeneous pattern (42/48) in PC, isovascular and homogenous (21/27) in AIP and MFP, and hypervascular and rapid stained (16/16) in PET were observed. The echo intensity reduction rate from the peak at 1 minute was the greatest in PC followed by MFP, AIP, and PET (P < 0.05). The diagnostic accuracies based on contrast imaging pattern (84.0%) and TIC (88.0%) were higher than those based on B-mode imaging (82.6%) and dynamic computed tomography (81.3%). In EUS in combination with TIC, sensitivity, specificity, and accuracy rose up to 95.8%, 92.6%, and 94.7%, respectively. CONCLUSIONS: Contrast-enhanced EUS with the dynamic quantitative analysis preparing TIC increased the diagnostic accuracy for pancreatic diseases.

Clinical oncology for pancreatic and biliary cancers: Advances and current limitations.

In the early 2000s, the main stream of endoscopic ultrasonography (EUS) changed from a mechanical scanning method to electronic radial or linear scanning methods. Subsequently, useful applications in trans-abdominal ultrasonography came within reach of EUS. In particular, contrast-enhanced EUS (CE-EUS) and EUS-elastography became cutting-edge diagnostic modalities for pancreatic disorders. Each type of pancreatic disorder has characteristic hemodynamics. CE-EUS uses color Doppler flow imaging and harmonic imaging to classify pancreatic lesions. EUS-elastography can assess tissue hardness by measuring its elasticity. This parameter appears to correlate with the malignant potential of the lesions. Tissue elasticity studies can provide information on both its pattern and distribution. The former is the conventional method of morphological diagnosis, but it is restricted to observations made in a region of interest (ROI). The latter is an unbiased analysis that can be performed by image analysis software and is theoretically constant, regardless of the ROI. Though EUS-fine needle aspiration (FNA) is also a very useful diagnostic tool, there are several limitations. Diagnostic EUS-FNA of pancreatic cystic lesions has marginal utility mainly due to low sensitivity. Therefore, in particular, endoscopists should keep this limitation in mind.

Organocatalytic asymmetric direct aldol reactions of trifluoroacetaldehyde ethyl hemiacetal with aromatic methyl ketones.

The organocatalytic asymmetric direct aldol reaction of trifluoroacetaldehyde ethyl hemiacetal with aromatic methyl ketones in the presence of a catalytic amount of (S)-5-(pyrrolidin-2-yl)-1H-tetrazole in dichloroethane at 40 °C proceeds smoothly to produce (R)-4,4,4-trifluoro-1-aryl-3-hydroxy-1-butanones in high yields with up to 90% ee.

Usefulness of EUS combined with contrast-enhancement in the differential diagnosis of malignant versus benign and preoperative localization of pancreatic endocrine tumors.

BACKGROUND: Pancreatic endocrine tumors (PETs) develop in relatively few patients, but they are often difficult to diagnose because of their small size and various clinical symptoms. OBJECTIVE: The aim of this study was to investigate the usefulness of EUS combined with contrast enhancement (CE-EUS) in the preoperative localization of PETs and the differentiation between malignant and benign PETs. DESIGN AND SETTING: Single-center retrospective study. PATIENTS: Sixty-two pathologically certified PETs of 41 patients who underwent EUS, multiphasic multidetector computed tomography (MDCT), and transabdominal US at our institute since 2001. INTERVENTIONS: Intravenous injection of US contrast media. MAIN OUTCOME MEASUREMENTS: Comparison of EUS, MDCT, and US in the preoperative identification of PETs, and the characteristic findings of EUS with malignancy. RESULTS: EUS showed high sensitivity (95.1%) in identifying PETs compared with MDCT (80.6%) and US (45.2%). Multivariable logistic regression analysis showed that heterogeneous ultrasonographic texture was the most significant factor for malignancy (OR = 53.33; 95% CI, 10.79-263.58). Most heterogeneous hypoechoic areas and anechoic areas corresponded to hemorrhage or necrosis on pathologic examination. They were identified as filling defects in CE-EUS and were more clearly recognized than in conventional EUS. LIMITATIONS: Retrospective study. CONCLUSION: EUS has higher sensitivity in preoperative localization of PETs compared with MDCT and US. The characteristics of EUS and CE-EUS findings in malignant PETs were clarified, and they will improve the diagnostic accuracy of PETs.