Hiroki Maeda

Usefulness of contrast-enhanced endoscopic sonography for discriminating mural nodules from mucous clots in intraductal papillary mucinous neoplasms: a single-center prospective study.

The aim of this study was to evaluate the ability of contrast‐enhanced endoscopic sonography for discrimination of mural nodules from mucous clots in intraductal papillary mucinous neoplasms of the pancreas.

Contrast-enhanced endoscopic ultrasonography can predict a higher malignant potential of gastrointestinal stromal tumors by visualizing large newly formed vessels

The aim of this study was to elucidate the histologic and clinical implications of detection of intratumoral vessels on contrast‐enhanced endoscopic ultrasonography (CE‐EUS) in gastrointestinal stromal tumors (GISTs).

Tumor vessel depiction with contrast-enhanced endoscopic ultrasonography predicts efficacy of chemotherapy in pancreatic cancer.

Objectives Contrast-enhanced endoscopic ultrasonography (CE-EUS) is a new imaging modality for pancreatic lesions. The aim of this study was to evaluate if CE-EUS is useful for predicting treatment efficacy before pancreatic cancer chemotherapy by assessing intratumoral vessel flow. Methods Thirty-nine patients with unresectable advanced pancreatic cancer underwent CE-EUS before chemotherapy. The patients were divided into 2 groups according to the intratumoral vessel flow observed with CE-EUS: vessel sign–positive and vessel sign–negative groups. Patient prognosis was investigated according to presence or absence of the vessel sign. Results Two patients were excluded due to poor visualization of CE-EUS images; therefore, 37 patients were analyzed. Contrast-enhanced EUS revealed positive vessel sign in 20 patients, whereas it revealed negative vessel sign in 17 patients. Both progression-free survival and overall survival were significantly longer in the positive- versus negative vessel sign groups (P = 0.037 and P = 0.027, respectively). Multivariate analysis demonstrated that the positive vessel sign was an independent factor associated with longer overall survival (hazard ratio, 0.22; 95% confidence interval, 0.08–0.53). Conclusions Evaluation of intratumoral vessel flow by CE-EUS could be useful for predicting efficacy of chemotherapy in patients with pancreatic cancer. Contrast-enhanced EUS could be used before chemotherapy for inoperable pancreatic cancer.

Contrast-Enhanced Endoscopic Ultrasonography for Pancreatic Tumors

Objectives. To investigate the usefulness of contrast-enhanced endoscopic ultrasonography (CE-EUS) for histological differentiation of pancreatic tumors. Methods. CE-EUS was performed for consecutive patients having a pancreatic solid lesion, and tumors were classified into three vascular patterns (hypervascular, isovascular, and hypovascular) at two time phases (early-phase and late-phase). Correlation between vascular patterns and histopathology of resected pancreatic cancer (PC) tissues was ascertained. Results. The final diagnoses of 147 examined tumors were PC (n = 109), inflammatory mass (n = 11), autoimmune pancreatitis (n = 9), neuroendocrine tumor (n = 8), and others (n = 10). In late-phase images, 104 of 109 PCs had the hypovascular pattern, for a diagnostic sensitivity and specificity of 94% and 71%, respectively. Of 28 resected PCs, 10 had isovascular, and 18 hypovascular, patterns on the early-phase image. Early-phase isovascular PCs were more likely to be differentiated than were early-phase hypovascular PCs (6 well and 4 moderately differentiated versus 3 well, 14 moderately, and 1 poorly differentiated, P = 0.028). Immunostaining revealed that hypovascular areas of early-phase images reflected heterogeneous tumor cells with fibrous tissue, necrosis, and few vessels. Conclusion. CE-EUS could be useful for distinguishing PC from other solid pancreatic lesions and for histological differentiation of PCs.

A case of chronic pancreatitis in which endoscopic ultrasonography was effective in the diagnosis of a pseudoaneurysm

Endoscopic ultrasonography (EUS) was performed on a patient being treated for chronic pancreatitis because a submucosal tumor was observed in the stomach during gastrointestinal endoscopy. As internal pulsatile blood flow on Doppler was present, the diagnosis of an aneurysm was made. The pseudoaneurysm of the left gastric artery was embolized with histoacryl and lipiodol and the splenic artery was embolized with coils at the location of the pseudoaneurysm to prevent hemorrhage. Follow up EUS confirmed the cessation of blood flow from the pseudoaneurysm. Clinicians encountering a gastric submucosal tumor-like protrusion in a patient with chronic pancreatitis should use EUS to investigate the possibility of a pseudoaneurysm, which must be treated as quickly as possible once identified.

Contrast Harmonic Sonographically Guided Radio Frequency Ablation for Spontaneous Ruptured Hepatocellular Carcinoma

Received January 19, 2005, from the Second Department of Internal Medicine, Wakayama Medical University, Wakayama, Japan (H.T., M.O., H.M., N.S., T.K., S.E., T.S., M.I., K.N., K.A., K.Y., Y.S., H.N., M.I.); and Department of Gastroenterology, University of Tokyo, Tokyo, Japan (M.F., N.Y., S.S.). Revision requested February 7, 2005. Revised manuscript accepted for publication March 1, 2005. Address correspondence to Hideyuki Tamai, MD, Second Department of Internal Medicine, Wakayama Medical University, 811-1 Kimiidera, Wakayama City, Wakayama 640-0012, Japan. Abbreviations CT, computed tomography; HCC, hepatocellular carcinoma; PEIT, percutaneous ethanol injection therapy; RFA, radio frequency ablation; S, segment; TAE, transcatheter arterial embolization ntraperitoneal bleeding due to a ruptured tumor is a serious complication in patients with hepatocellular carcinoma (HCC). According to data compiled by the Liver Cancer Study Group of Japan,1 ruptured HCC accounts for around 10% of deaths in these patients. Clinical features include the sudden onset of abdominal pain and distension and, if bleeding is massive, the presence of shock. Other causes of an acute abdominal emergency must be ruled out. Diagnostic imaging generally includes sonography, contrast computed tomography (CT), and angiography. In patients with ruptured HCC, prompt diagnosis and treatment is essential to avoid hepatocyte necrosis and secondary hepatic failure associated with shock and decreased hepatic perfusion due to bleeding. The underlying liver disease varies in such patients with ruptured HCC. Chronic hepatitis, cirrhosis, or both may be present, and the severity of hepatic dysfunction as well as the size, number, and progression of the neoplastic lesions present varies from case to case. A common feature is the presence of a responsible lesion on or protruding from the surface of the liver. If hemostasis can be achieved early after HCC rupture, then overall prognosis depends on the patient’s liver function and degree of tumor progression. Although there is a risk of intraperitoneal seeding, long-term survival is possible if the tumor can be completely resected by hepatectomy. One study has already reported a good 5-year survival rate after resection of ruptured and nonruptured HCC.2 In another study, rather than performing emergency surgery, Marini et al3 used transcatheter arterial embolization (TAE) to control bleeding; in those patients who could then undergo surgery, elective hepatectomy was associated with long-term survival. Treatment of ruptured HCC involves more than just hemostasis. Subsequent therapy is important, and, whenever possible, complete resection should be performed after bleeding has been controlled.

Rapid On-Site Evaluation by Endosonographers during Endoscopic Ultrasonography-Guided Fine-Needle Aspiration for Diagnosis of Gastrointestinal Stromal Tumors

Background/Aims Endoscopic ultrasonography-guided fine-needle aspiration (EUS-FNA) has been used to diagnose gastrointestinal submucosal tumors (SMTs). Although rapid on-site evaluation (ROSE) has been reported to improve the diagnostic accuracy of EUS-FNA for pancreatic lesions, on-site cytopathologists are not routinely available. Given this background, the usefulness of ROSE by endosonographers themselves for pancreatic tumors has also been reported. However, ROSE by endosonographers for diagnosis of SMT has not been reported. The aim of this study was to evaluate the diagnostic accuracy of EUS-FNA with ROSE by endosonographers for SMT, focusing on diagnosis of gastrointestinal stromal tumor (GIST), compared with that of EUS-FNA alone. Methods Twenty-two consecutive patients who underwent EUS-FNA with ROSE by endosonographers for SMT followed by surgical resection were identified. Ten historical control subjects who underwent EUS-FNA without ROSE were used for comparison. Results The overall diagnostic accuracy for SMT was significantly higher in cases with than without ROSE (100% vs. 80%, p=0.03). The number of needle passes by FNA with ROSE by endosonographers tended to be fewer, although accuracy was increased (3.3±1.3 vs. 5.9±3.8, p=0.06). Conclusions ROSE by endosonographers during EUS-FNA for SMT is useful for definitive diagnosis, particularly for GIST.

The Wire-Grasping Method as a New Technique for Forceps Biopsy of Biliary Strictures: A Prospective Randomized Controlled Study of Effectiveness

Background/Aims Transpapillary forceps biopsy is an effective diagnostic technique in patients with biliary stricture. This prospective study aimed to determine the usefulness of the wire-grasping method as a new technique for forceps biopsy. Methods Consecutive patients with biliary stricture or irregularities of the bile duct wall were randomly allocated to either the direct or wire-grasping method group. In the wire-grasping method, forceps in the duodenum grasps a guide-wire placed into the bile duct beforehand, and then, the forceps are pushed through the papilla without endoscopic sphincterotomy. In the direct method, forceps are directly pushed into the bile duct alongside a guide-wire. The primary endpoint was the success rate of obtaining specimens suitable for adequate pathological examination. Results In total, 32 patients were enrolled, and 28 (14 in each group) were eligible for analysis. The success rate was significantly higher using the wire-grasping method than the direct method (100% vs 50%, p=0.016). Sensitivity and accuracy for the diagnosis of cancer were comparable in patients with the successful procurement of biopsy specimens between the two methods (91% vs 83% and 93% vs 86%, respectively). Conclusions The wire-grasping method is useful for diagnosing patients with biliary stricture or irregularities of the bile duct wall.

Mo1518 An Evaluation of Risk Factors for Inadequate Cytology Using Contrast-Enhanced Harmonic Endoscopic Ultrasound in Endoscopic Ultrasound-Guided Fine Needle Aspiration of Suspected Pancreatic Malignancy

An Evaluation of Risk Factors for Inadequate Cytology Using Contrast-Enhanced Harmonic Endoscopic Ultrasound in Endoscopic Ultrasound-Guided Fine Needle Aspiration of Suspected Pancreatic Malignancy Masahiro Itonaga*, Kazuki Ueda, Hiroko Terada, Takashi Tamura, Yasunobu Yamashita, Hiroki Maeda, Takao Maekita, Mikitaka Iguchi, Hideyuki Tamai, Jun Kato, Masao Ichinose Second Department of Internal Medicine, Wakayama Medical University, Wakayama City, Japan [OBJECTIVES] Contrast-enhanced harmonic endoscopic ultrasound(CH-EUS) is useful for differential diagnosis of pancreatic mass lesions, but risk factors for inadequate cytology using this modality in endoscopic ultrasound-guided fine needle aspiration(EUS-FNA) remain unclear. The present study aimed to evaluate the role of CH-EUS in EUS-FNA. [METHODS] Generally, CH-EUS is evaluated in the perfusion phase (60-90 s after contrast agent infusion), but we performed evaluations in the early phase (10-30s after contrast agent infusion) and categorized into two patterns: Pattern A, homogeneous enhancement; and Pattern B, heterogeneous enhancement with partial hypoenhancement. We selected typical Pattern A and Pattern B cases of pancreatic ductal adenocarcinoma that had undergone surgery and performed histopathological examinations with hematoxylin and eosin staining and immunohistochemical staining. Compared with Pattern A, the Pattern B case showed necrotic or fibrous lesions and fewer vessels. The Pattern A case showed tumor cells homogeneously, but the Pattern B case showed few tumor cells in the necrotic or fibrous regions and tumor cells were distributed heterogeneously. We thus hypothesized that accuracy of EUS-FNA would differ between Patterns A and B. From January 2009 to July 2012, a total of 61 patients with suspected pancreatic malignancy were included. After CH-EUS was performed, we performed EUSFNA at the center of each mass. Risk factors for inadequate cytology were evaluated retrospectively. [RESULTS] Male:female ratio was 36:25, mean ( standard deviation) age was 68.8 8.96 years, mean lesion size was 37.6 15.3 cm, head:body or tail ratio was 28:33; 19G/22G ratio was 37/24; number of passes was 2.77 1.28 and Pattern A:B ratio was 23:38. FNA was successfully performed in all cases and adequate samples for histological examination were obtained in 53 of the 61 cases (86.9%). Only Pattern B was identified as a significant risk factor for inadequate cytology (p 0.02) using the 2-test and Student’s t-test. [CONCLUSION] As expected, accuracy in EUS-FNA differed significantly between Patterns A and B. We expect CH-EUS to improve the diagnostic value of EUS-FNA if regions of hypoenhancement on CH-EUS are avoided.

Common Bile Duct Dilatation With Stones Indicates Requirement for Early Drainage in Patients With or Without Cholangitis

Background Some patients with common bile duct (CBD) stones develop cholangitis requiring drainage, while others do not. The aims of this study were to elucidate the clinical differences among patients with CBD stones who required and did not require emergent drainage, and to identify risk factors for the development of cholangitis requiring emergent drainage in patients with silent CBD stones. Methods Clinical characteristics of consecutive patients with CBD stones who underwent endoscopic removal of stones or biliary drainage were analyzed retrospectively. Results Of 101 patients analyzed, 32 had moderate or severe cholangitis as the indication for emergent drainage, and the remaining 69 did not. Patients who required emergent drainage were more likely to have gallstones (P = 0.029), dilated CBD (> 10 mm) (P = 0.004) and larger CBD stones (P = 0.019). By multivariate analysis, CBD dilation was the only significant differentiating clinical characteristic of the patients who required emergent drainage (OR = 3.75, 95% CI: 1.41-9.96, P = 0.008). Of the 35 patients with silent bile duct stones, eight required emergent endoscopic drainage during the waiting period. CBD dilation was also the only significant risk factor for the development of moderate or severe cholangitis among patients with silent bile duct stones (OR = 10.18, 95% CI: 1.09-94.73, P = 0.042). Conclusions Dilated CBD (> 10 mm) was the only risk factor identified for requirement of early drainage in patients with CBD stones. Those who have silent CBD stones with CBD dilatation should undergo early drainage.