Manabu Sen-yo

UNILATERAL VERSUS BILATERAL DRAINAGE USING SELF-EXPANDABLE METALLIC STENT FOR UNRESECTABLE HILAR BILIARY OBSTRUCTION

Background:  There is no consensus on the choice of either unilateral or bilateral drainage in stent placement for patients with unresectable hilar biliary obstruction. The aim of the present study was to clarify which drainage method is superior.

Bench-top testing of suction forces generated through endoscopic ultrasound-guided aspiration needles

Adequate needle size and tissue acquisition techniques for endoscopic ultrasound‐guided fine needle aspiration (EUS‐FNA) need further elucidation. Moreover, the actual negative pressure and suction forces of FNA needles remain unknown. We evaluated the suction forces of 19‐gauge, 22‐gauge, and 25‐gauge conventional FNA needles and side hole aspiration needles using conventional negative pressure and the slow pull technique.

Clinical impact of endoscopic papillectomy for benign–malignant borderline lesions of the major duodenal papilla

Background and purposeThe present study retrospectively analyzed the clinical impact of endoscopic papillectomy on the selection of a treatment strategy for patients with benign–malignant borderline lesions of the major duodenal papilla.Patients and methodsBetween November 1995 and July 2009, 28 patients were selected for endoscopic papillectomy. The clinical impact of endoscopic papillectomy was assessed. Snare resection was performed in a radical fashion.ResultsAn endoscopic papillectomy was technically feasible in all patients. En bloc excision was achieved in 22 cases (79%). The final histopathological diagnoses of the endoscopic specimen were 17 adenoma (61%), 7 carcinoma in adenoma (25%), and 4 adenocarcinoma (14%). Two out of the four adenocarcinoma cases were referred for surgery. The other two patients with negative margins have not experienced recurrences during the follow-up period. A residual tumor was detected in 1 out of 17 cases (6%) of adenoma and 2 out of 7 cases (29%) of carcinoma in adenoma.ConclusionsEndoscopic papillectomy is therefore considered to be an effective treatment for patients with a benign–malignant borderline lesion of the major duodenal papilla. This method also has an important clinical impact because it provides an accurate diagnosis, aids in the selection of an appropriate treatment strategy, and reduces unnecessary surgery.

Successful retrieval of an impacted mechanical lithotripsy basket: a case report.

We report the successful retrieval of an impacted mechanical lithotripsy basket. In a patient with two large common bile duct stones, the basket with the entrapped stone was impacted within the mid‐common bile duct. We then attempted to use another mechanical lithotripter; however the central wire of the basket fractured at the handle portion. Grasping a few wires of the impacted basket with rat‐tooth forceps allowed the wires of the basket to slip away from the stone. The present report describes the safe and effective use of rat‐tooth forceps in the management of an impacted lithotripter basket.

GENETIC DIAGNOSIS OF PANCREATIC CANCER USING SPECIMENS OBTAINED BY EUS-FNA

We review the current situation concerning molecular biological analysis in respect of pancreatic cancer, using specimens obtained by endoscopic ultrasound‐guided fine‐needle aspiration (EUS‐FNA). K‐ras, p53, p16, DPC4/SMAD4, telomerase activity are used for discrimination between tumor‐forming pancreatitis and pancreatic cancer. Examination of heat shock protein (HSP) 27, ribonucleotide reductase, and other factors are examined in order to test the sensitivity to Gemcitabin. Comparative genomic hybridization analysis for pancreatic cancer specimens obtained by EUS‐FNA was reported to be useful for evaluate the biological characteristics of pancreatic cancer before treatment. It is expected that the genetic diagnosis using EUS‐FNA specimens will not only positively contribute to improving the diagnostic performance, but it will also provide valuable information for carrying out tailor‐made treatment.

Utility of the Anterior Oblique-Viewing Endoscope and the Double-Balloon Enteroscope for Endoscopic Retrograde Cholangiopancreatography in Patients with Billroth II Gastrectomy

Background/Purpose. The difficulties of endoscopic retrograde cholangiopancreatography in patients with Billroth II gastrectomy have been reported. We evaluated the usefulness of an anterior oblique-viewing endoscope and a double-balloon enteroscope for endoscopic retrograde cholangiopancreatography in such patients. Methods. From January 2003 to December 2011, 65 patients with Billroth II gastrectomy were enrolled in this study. An anterior oblique-viewing endoscope was used for all patients. From February 2007, a double-balloon enteroscope was used for the failed cases. The success rate of procedures was compared with those in 20 patients with Billroth II gastrectomy using forward-viewing endoscope or side-viewing endoscope from March 1996 to July 2002 as historical controls. Results. In all patients in whom the papilla was reached (60/65), selective cannulation was achieved. The success rate of selective cannulation and accomplishment of planned procedures in the anterior oblique-viewing endoscope group were both significantly higher than that in the control group (100% versus 70.1%, 100 versus 58.8%, resp.). A double-balloon enteroscope was used in 2 patients, and the papilla could be reached and the planned procedures completed. Conclusions. An anterior oblique-viewing endoscope and double-balloon enteroscope appear to be useful in performing endoscopic retrograde cholangiopancreatography in patients with Billroth II gastrectomy.

Efficacy of contrast-enhanced harmonic endoscopic ultrasonography in the diagnosis of pancreatic ductal carcinoma.

Background/Aims: Distinguishing pancreatic ductal carcinoma (DC) from other pancreatic masses remains challenging. This study aims at evaluating the efficacy of contrast-enhanced harmonic endoscopic ultrasonography (CEH-EUS) in the diagnosis of DC. Patients and Methods: Forty-nine patients with solid pancreatic mass lesions underwent CEH-EUS. EUS (B-mode) was used to evaluate the inner echoes, distributions, and borders of the masses. The vascular patterns of the masses were evaluated with CEH-EUS at 30–50 s (early phase) and 70–90 s (late phase) after the administration of Sonazoid®. Results: The final diagnoses included DCs (37), mass-forming pancreatitis (6), endocrine neoplasms (3), a solid pseudopapillary neoplasm (1), a metastatic carcinoma (1), and an acinar cell carcinoma (1). The sensitivity, specificity, and accuracy of the diagnoses of DC in hypoechoic masses using EUS (B-mode) were 89.2%, 16.7%, and 71.4%, respectively. The sensitivity, specificity, and accuracy for the diagnosis of DC in hypovascular masses using CEH-EUS were 73.0%, 91.7%, and 77.6% in the early phase and 83.8%, 91.7%, and 85.7% in the late phase, respectively. Conclusions: CEH-EUS for the diagnosis of DC is superior to EUS. CEH-EUS in the late phase was particularly efficacious in the diagnosis of DC.

Su1471 Clinical Observation Is Possible for Branch Duct Type Intraductal Papillary Mucinous Neoplasms With Mural Nodules ≤6mm

Introduction: The presence of mural nodule (MN) is an important factor for the management of branch duct type intraductal papillary mucinous neoplasm (BD-IPMN). International consensus guidelines 2012 recommend clinical follow-up to BD-IPMN without MNs. However, it is not clear whether BD-IPMNs with MNs need surgical treatment regardless of the height of MNs. Aim: To compare the pathological and follow-up outcomes between BDIPMNs with MNs ≤6mm in height (MN+) and those without MNs (MN-). Methods: The patients who were diagnosed as BD-IPMNs with MNs ≤6mm or without MNs since April 2004 to December 2013 were retrospectively analyzed. Inclusion criteria were the obtaining of contrast enhanced CT and EUS at initial diagnosis, and surgical resection in our center or follow-up with annual/semi-annual CT/MRCP. The cyst size and main pancreatic duct (MPD) diameter were measured by CT/MRCP, while MN height was measured by EUS. Tumor progression during follow-up was defined as follows; increased cyst size ≥10mm; increased MPD diameter ≥10mm; new development of MN or increased MN height ≥2mm. Evaluation points: 1) pathological diagnosis of resected BD-IPMN, 2) follow-up outcomes Results: Among 656 patients of BD-IPMNs diagnosed in our center, MN height was evaluated as less than or equal to 6mm in 511(78%; MN+ 50, MN352). After initial diagnosis, 17(3%; MN+ 8, MN9) of them underwent immediate resection and 385(75%; MN+ 42, MN343) of them received regular follow-up, who were eligible for this analysis. The median cyst size and MPD diameter were 20(10-70) mm and 3(2-12) mm, respectively. The median height of MNs in MN+ were 3(1-6) mm. 1) The pathological diagnosis of the patients with MNwere all low/intermediate-grade dysplasia (LID), while those of the patients with MN+ were LID in 5, high-grade dysplasia (HD) in 2, and invasive carcinoma (IC) in 1. There were no significant differences in pathological diagnosis between MN+ and MN(p=0.17, chi-square test). 2) During a median follow-up period of 3.4(0.5-10.6) years, 49(13%; MN+ 9, MN40) patients exhibited tumor progression. The 5-years cumulative tumor progression rate was higher in MN+ than those in MN(MN+ 19% vs MN9%; p<0.01, Log-rank test). Among 49 patients with tumor progression, 11(22%; MN+ 4, MN7) patients underwent surgical resection, whose pathological diagnosis were LID in 6(MN+ 2, MN4), HD in 3(MN+ 1, MN2), and IC with minimal invasion in 2(MN+ 1, MN1). The other 38 patients continued to be followed during a median period of 0.6(0.0-4.2) years. Meanwhile, concomitant pancreatic ductal adenocarcinoma (PDAC) was appeared in 9(2%; MN+ 1, MN8) patients. Conclusion: Although tumor progression rate was higher, BD-IPMN with MNs ≤6mm in height on EUS could be managed conservatively. However, careful attention should be paid to the development of PDAC during follow-up.