DIAGNOSTIC UTILITY OF PERORAL CHOLANGIOSCOPY AND TRANSPAPILLARY INTRADUCTAL ULTRASONOGRAPHY FOR BILE DUCT CARCINOMA

Recently, new diagnostic procedures such as video peroral cholangioscopy (POCS) and transpapillary intraductal ultrasonography (IDUS) have been available for diagnosis of biliary diseases. These new modalities are especially useful for diagnosis of minute bile duct lesions on cholangiogram and correct diagnosis of lateral extension of bile duct carcinoma. In this paper, showing some effective cases of POCS and IDUS, we present our diagnostic approach for bile duct carcinoma and discuss the future prospects of POCS and IDUS.     

THE ROLE OF PERORAL CHOLANGIOSCOPY FOR BILE DUCT LESIONS

We reviewed the current status of peroral cholangioscopy under duodenoscopic assistance, which allows direct visualization of the bile duct. Direct visual assessment may be a useful adjunct to endoscopic retrograde cholangiopancreatography (ERCP) for distinguishing malignant from benign bile duct lesions. Several clinical studies suggest the efficacy of peroral cholangioscopy for various bile duct lesions. However, solely cholangioscopic examination may be insufficient to confirm accurate differential diagnosis between benign and malignant strictures or tumor extension of bile duct carcinoma. Directed tissue acquisition in biliary strictures by using peroral cholangioscopy is another application that has not been properly studied because of the limited maneuverability of the long babyscope. Further improvement of suitable instruments and cholangioscopes are needed.     

ROLE OF PERORAL CHOLANGIOSCOPY IN THE PREOPERATIVE DIAGNOSIS OF MALIGNANT MIDDLE and LOWER BILE DUCT CANCERS: A PRELIMINARY STUDY USING 10 FR PLASTIC STENT

To date, peroral cholangioscopy (POCS) with working channel for biopsy is a less than an essential means for endoscopic diagnosis of bile duct lesions. One of these reasons is that the durability of the baby scope is much improved, too delicate for use on tough lesions. Furthermore, in operable cases, it has a major disadvantage in that we cannot observe the proximal site of stricture. In this study, we introduced new methods to observe and perform the biopsy at proximal site of stricture using 10Fr plastic stent. After this method, we performed observation of proximal site of stricture without dilation and could diagnose precise incision line preoperatively in all cases. Importantly, all procedures were done within one week from the first endoscopic retrograde cholangiopancreatography (ERCP). Although further investigation and development of baby scopes are necessary, POCS using 10Fr plastic stent will make it possible to evaluate the hepatic site of spreading cancer in patients with middle or lower bile duct cancer.     

PERORAL CHOLANGIOSCOPY: AN IMPROVED PROCEDURE

Cholangioscopy provides direct visual assessment of the bile ducts, tissue sampling, and therapeutic interventions. Delineation of intraductal lesions equivocal with direct cholangiography, differentiation between malignant and benign biliary strictures, and assessment of longitudinal extent of cholangiocarcinoma are major indicators for diagnostic cholangioscopy. Peroral cholangioscopy is readily performed at an initial endoscopic retrograde cholangiopancreatography. Owing to substantial refinement in terms of image quality and technical feasibility achieved with the development of a new video cholangioscope, peroral cholangioscopy has become a powerful tool. However, compared with percutaneous cholangioscopy, there remain several disadvantages in peroral cholangioscopy: less favorable maneuverability, small instrumental channel, and limited therapeutic instrumentations. With further advances in endoscopic functions and increasing availability of suitable instruments, peroral cholangioscopy, because of its less invasiveness, will become mandatory for diagnostic and therapeutic biliary endoscopy.     

TWO CASES OF MUCIN‐PRODUCING CHOLANGIOCARCINOMA DIAGNOSED BY PERORAL CHOLANGIOSCOPY

Mucin‐producing cholangiocarcinoma, which excretes excessive amounts of mucin into the biliary tract and causes obstructive jaundice and cholangitis due to the mucin retention, is rare. In this paper, we report two cases of this disease, which were demonstrated by peroral cholangioscopy (POCS). The radiologic features of these tumors show the diffuse dilatation of the bile ducts demonstrated by computed tomography (CT) and ultrasonography (US), the amorphous filling defects in the dilated bile ducts revealed by cholangiography. Their endoscopic features are mucin flowing out from the papilla of Vater during endoscopic retrograde cholangiography (ERC), and the papillary tumor with contiguous superficial spread in the bile ducts observed by cholangioscopy, although removal of mucin in the biliary tract is sometimes necessary before cholangioscopy in order to examine the lesion sufficiently. According to the previous reports, prognosis after curative resection of these tumors is better than that of ordinary type of cholangiocarcinoma. Therefore, it is important to examine the tumor extension in the bile ducts by cholangioscopy, although a selection of route inserting cholangioscope is controversial.     

A CASE WITH GALLBLADDER CANCER DIAGNOSED BY PERORAL CHOLECYSTOSCOPY (POCCS) AFTER LITHOTRIPSY IN THE COMMON BILE DUCT STONES

A 76‐year‐old woman was admitted for treatment of obstructive jaundice. An abdominal computed tomography revealed common bile duct stones and gallstones in addition to gallbladder wall thickness. The endoscopic retrograde cholangiopancreatography (ERCP) also revealed common bile duct stones, gallstones, and irregular imaging of gallbladder wall. After lithotripsy in the bile duct completely, we observed inside the gallbladder by peroral cholecystoscopy (POCCS). POCCS findings and biopsy under direct vision showed papillary adenocarcinoma were observed in body of the gallbladder.     

CLINICAL EVALUATION OF PERORAL CHOLANGIOSCOPY FOR BILIARY DISEASE USING NARROW BAND IMAGING

Regarding peroral cholangioscopy (POCS) for biliary disease, due to the recent appearance of a video cholangioscope that can obtain high‐quality images, it is possible to observe subtle changes of the biliary mucosa. In addition to the conventional observation method using POCS, the biliary mucosa with also observed with narrow band imaging (NBI) in one case of chronic cholangitis and four cases of extra hepatic bile duct tumor (three surgical cases). In the conventional observation method, the vessels in the surface layer of the biliary mucosa could be observed more clearly using NBI. In one case in which a tumor was observed, the irregularity of the biliary mucosa became clear on NBI, and the vessels inside a papillary tumor could also be easily observed. In another case of bile duct tumor, the conventional observation method showed a region in the proximity of the tumor where the vessels could not be seen clearly, but they could be seen clearly on NBI. In all of the cases, the bile juice was seen as red on NBI, which disturbed the observation. With POCS using NBI, it was possible to observe the vessels and irregularities in the surface layer of the biliary mucosa more clearly than with conventional observation methods.     

ENDOSCOPIC OBSERVATION OF MUCOSAL SPREAD LESION OF CHOLANGIOCARCINOMA USING PERORAL CHOLANGIOSCOPY WITH NARROW BAND IMAGING

A 69‐year‐old man was admitted to Toho University Omori Medical Center complaining of icterus. Abdominal computed tomography, magnetic resonance cholangiopancreatography and endoscopic retrograde cholangiopancreatography were suspicious of cholangioma of inferior bile duct. Peroral cholangioscopy using narrow band imaging (NBI) was performed and it was possible to diagnose the mucosal spread lesions of cholangioma. Histological findings reflected the endoscopic findings. Mucosal spread lesions of cholangiocarcinoma were successfully diagnosed using the CHF‐B260 for NBI.     

DIRECT PERORAL CHOLANGIOSCOPY AND PANCREATOSCOPY FOR DIAGNOSIS OF A PANCREATOBILIARY FISTULA CAUSED BY AN INTRADUCTAL PAPILLARY MUCINOUS NEOPLASM OF THE PANCREAS: A CASE REPORT

Here, we report a case of a pancreatobiliary (PB) fistula caused by an intraductal papillary mucinous neoplasm (IPMN) of the pancreas. The PB fistula was suspected after endoscopic retrograde cholangiopancreatography (ERCP) and diagnosed after direct visualization with a direct peroral cholangioscopy and pancreatoscopy by using an ultra‐slim endoscope. No previous reports exist on the precise diagnosis of a PB fistula with direct peroral cholangioscopy and pancreatoscopy. In our case report, a 69‐year‐old man underwent an ERCP because of a pancreatic head mass and biliary tract obstruction. During ERCP, a fistula between the common bile duct (CBD) and main pancreatic duct (MPD) was suspected. After endoscopic sphincterotomy, we examined both the CBD and MPD with an ultra‐slim videoendoscope (GIF‐N260; Olympus Optical Co, Tokyo, Japan) under direct visualization and biopsy of the mass. The analysis of the biopsy specimen confirmed this mass to be an IPMN of the pancreas. When we examined the CBD, one fistula with copious mucin secretion was identified at the distal CBD. In conclusion, direct peroral cholangioscopy and pancreatoscopy using the ultra‐slim endoscope is an efficient tool for diagnosis of PB fistula and pancreatic IPMN.     

LIMITATIONS OF PERORAL CHOLANGIOSCOPY IN THE DIAGNOSIS OF BILIARY TUMORS

In patients with carcinoma of the bile duct, a primary tumor with tumor spread along the bile duct is frequently shown as a stricture of the bile duct with ductal irregularity and rigidity on ERCP. In patients in whom histological diagnosis is necessary, larger caliber peroral cholangioscopes with a larger working channel should be chosen because they have the advantage of simultaneous biopsy diagnosis. However, peroral cholangioscopy (POCS) has limitations to inspect mucosal tumor spread along the upstream ducts due to the tight stricture, to obtain sufficient biopsy material for confirming the diagnosis, and to identify submucosal tumor spread. With further improvement of techniques, the combined use of POCS with biopsy under direct vision and intraductal ultrasonography (IDUS) is expected to be the best way in the diagnosis of biliary tumors.     

ENDOSCOPIC PAPILLARY LARGE BALLOON DILATION AFTER ENDOSCOPIC SPHINCTEROTOMY FOR TREATMENT OF LARGE COMMON BILE DUCT STONE

The extraction of large common bile duct (CBD) stones after an endoscopic sphincterotomy is successful in most cases. However, the procedure often requires a prolonged time and repeated trials, therefore, subsequent occurrence of procedure‐related complications are not uncommon. The purpose of the present paper was to investigate the utility of a combined endoscopic papillary large balloon dilation (EPLBD) preceded by a mid‐incision endoscopic sphincterotomy for the removal of large CBD stones. Stone removal was surprisingly effective with EPLBD in patients with large CBD stones. Occurrence of major complication, such as pancreatitis, bleeding, and perforation, was not observed in any patients who were treated with EPLBD. EPLBD also can be safely carried out on patients with anatomic alteration, such as a periampullary diverticulum, and on patients who have undergone a Billroth II operation. EPLBD is a landmark method of removing a large CBD stone, the impact of which is comparable to that of the introduction of endoscopic mechanical lithotripsy. However, further investigation is required to address the applications and potential outcomes of this procedure. Also, procedure guidelines should be established to avoid major complications.     

COVERED WALLSTENT FOR PALLIATION OF MALIGNANT COMMON BILE DUCT STRICTURE: PROSPECTIVE MULTICENTER EVALUATION

Background: Occlusion due to tumor ingrowth is a major drawback in self‐expandable metallic stents. Covering the stent is a probable solution to prevent tumor ingrowth. A manufactured covered self‐expandable metallic stent, Covered Wallstent, has become commercially available. We evaluated the Covered Wallstent in a prospective uncontrolled multicenter setting. Methods: Between October 2001 and October 2003, 97 patients with common bile duct strictures deemed unfit for surgical resection underwent placement of a single Covered Wallstent, and were followed prospectively until April 2004. Results: Placement of the stent was successful in all the patients attempted. As a procedure‐related complication, acute pancreatitis developed in four patients, in one of whom obstruction of the pancreatic duct orifice with the stent body seemed to be a major cause. The 30‐day mortality was 9.3% (nine patients). Stent occlusion occurred in 22 patients as a late (greater than 30 days) complication, due to either tumor overgrowth (14 patients) or encrustation (eight patients). Distal migration of the stent was demonstrated in two other patients. No stent occlusions due to tumor ingrowth were observed. Patency rates of the stent for 3‐, 6‐, and 12‐month periods were, respectively, 90.7, 82.5, and 45.9%. Conclusions: The present results in a large series suggest that placement of the Covered Wallstent is feasible and effective in the palliation of patients with malignant common bile duct strictures. The Covered Wallstent seems to be reliable in eliminating tumor ingrowth. The role of stent covering in promoting stent function should be examined in a prospective comparative study between covered‐ and uncovered Wallstents.     

INTRADUCTAL ULTRASONOGRAPHY FOR THE STAGING OF BILE DUCT CARCINOMA

Intraductal ultrasonography is useful in the staging of extrahepatic bile duct cancer including tumor depth infiltration, pancreatic parenchymal invasion, portal vein invasion, and right hepatic artery invasion. However, it has limitations in assessing lymph node metastases. The assessment of longitudinal cancer extension along the bile duct is a promising aspect of this area. However, a thickening of the bile duct wall may represent either inflammatory changes that may result from mechanical irritation by a biliary drainage catheter or other factors, or the longitudinal extension of the cancer.     

INFLAMMATORY PROTRUDING LESION IN THE INTRAHEPATIC BILIARY DUCT DIAGNOSED ON NARROW BAND IMAGING–VIDEOCHOLANGIOSCOPY

A 66‐year‐old woman who had a repeated history of cholangitis since undergoing choledocho‐jejunostomy for post‐cholecystectomy common bile duct stricture, was referred to Kyoto University Hospital for further examination of the stricture of left intrahepatic biliary duct (IHBD). Endoscopic retrograde cholangiography (ERC) showed obstruction of the left IHBD with slightly protruding lesion. Peroral cholangioscopy (POCS) with narrow band imaging (NBI) demonstrated that a protruding lesion with papillary surface had neither tumor vessels on the surface of the tumor nor microvessel in each papillary projection. Biopsy presented only inflammation. Pathological analysis of the resected left lobe also showed only inflammatory change. NBI‐videocholangioscopy appears to be useful for diagnosing biliary disease by evaluating the tumor vessels including microvessel in papillary projection.     

OPTIMUM NUMBER OF PERCUTANEOUS TRANSHEPATIC CHOLANGIOSCOPY‐GUIDED BIOPSIES FOR HISTOLOGIC DIAGNOSIS OF BILE DUCT CARCINOMA

Background: Percutaneous transhepatic cholangioscopy (PTCS)‐guided biopsy is used for the diagnosis of bile duct carcinoma, but the number of biopsy specimens required for diagnosis is unclear. The aim of this study was to clarify whether multiple PTCS‐guided biopsies are needed for accurate histologic diagnosis. Methods: We examined the relationships between size of the first biopsy specimen, endoscopic, cholangiographic, and pathologic features, and the presence of carcinoma in the first biopsy specimen of the primary lesion in 27 bile duct carcinomas. Results: Twenty‐six of 27 carcinomas (96%) were histologically diagnosed by PTCS‐guided biopsy; 20 (74%) were detected in the first biopsy specimen, six in the second or third biopsy specimen, and one was not detected in four biopsy specimens. Carcinomas with papillogranular mucosa by endoscopy, convex margins by cholangiography, or macroscopic types (except for sclerosing type) were detected on the first biopsy specimen more frequently than were others (15/15 vs 5/12, P <0.001; 13/13 vs 7/14, P <0.01; and 15/16 vs 5/11, P <0.01, respectively). There was no relationship between positivity for carcinoma and size of the first biopsy specimen, vascular dilatation by endoscopy, or histologic type. With the combination of preoperative endoscopy and cholangiography, main lesions with papillogranular mucosa and/or convex margins were proven to be carcinoma on the first biopsy specimen significantly more frequently than were others (17/17 vs 3/10, P <0.0001). Conclusion: If the main lesion contains neither papillogranular mucosa nor a convex margin, multiple PTCS‐guided biopsies should be performed in order to increase the sensitivity for diagnosing bile duct carcinoma.     

鼠胆管结扎性肝损伤时肾神经与钠瀦留的关系

将动物分为４组：对照组；单纯肾神经去除组；单纯胆管结扎组；胆管结扎＋双肾神经去除组。术后１６天，观察各组血浆肾素活性及肾对钠的代谢作用。结果发现，与对照组相比，双肾神经去除组各指标间无显著变化，胆管结扎鼠血浆肾素活性显著升高，钠代谢呈显著正平衡（＋６７２±２４．３％），显著高于其它３组（Ｐ＜０．０１），而胆管结扎＋双肾神经去除鼠钠平衡代谢无显著变化，提示：肾神经在胆管结扎鼠钠　留中发挥重要作用。     

磁共振胆胰管成像对老年性胆总管扩张患者诊断价值

目的老年性胆总管扩张患者磁共振胆胰管成像（magnetic resonance cholangiopancreatography，MRCP）的诊断和鉴别诊断价值评估。方法回顾性分析197例老年性胆总管扩张患者MRCP检查及临床诊断与治疗结果进行比较。结果MRCP诊断为胆总管下端结石68例，急性胆囊炎，胆囊结石伴胆总管扩张57例，胆囊切除术后改变38例，胆囊颈管结石22例，胆道系统肿瘤7例，胰腺占位性病变5例，诊断符合率99．5％结论MRCP在老年性胆总管扩张的病因诊断和鉴别诊断中有重要价值。     

RISK MANAGEMENT FOR ENDOSCOPIC TREATMENT FOR COMMON BILE DUCT STONES: ENDOSCOPIC SPHINCTEROTOMY AND ENDOSCOPIC PAPILLARY BALLOON DILATION

Currently, endoscopic treatment for common bile duct stones is widely performed all over the world. Endoscopic sphincterotomy (EST) and endoscopic papillary balloon dilation (EPBD) are representative treatments of this modality in Japan. Both of them are much more convenient and much less invasive than surgical operation. These two procedures are also recognized as being relatively safe, but it is also a fact that serious complications may still occur at a certain rate. Bleeding, pancreatitis and duodenal perforation can occur in association with EST, and pancreatitis is the most important issue related to EPBD. To reduce the risk, these procedures should be performed only under the appropriate indications and in an appropriate manner. In addition, several special medications and treatments before and/or after the procedure might also be useful in reducing the risks associated with it.     

老年肝门部胆管癌的诊治特点

目的探讨老年肝门部胆管癌的诊治特点。方法回顾性分析111例60岁以上肝门部胆管癌的临床资料及随访情况。结果43例行肿瘤根治性切除，10例行肿瘤姑息性切除，20例行手术胆道引流，38例行内镜置管或PTCD引流。行根治性或姑息性肿瘤切除的患者，减黄效果、生活质量改善及术后生存时间均明显优于其他方法。结论对老年肝门部胆管癌的手术治疗应持积极态度。     

INTRADUCTAL ULTRASONOGRAPHY IN THE DIAGNOSIS OF BILE DUCT STONES: WHEN AND WHOM?

Background and Aim: Biliary intraductal ultrasonography (IDUS) is highly sensitive in visualizing bile duct stones (BDS). Indications for IDUS, however, in cases of suspected BDS have not yet been established. The aim of the present study was to elucidate adequate indications for IDUS in cases that undergo endoscopic retrograde cholangiopancreatography (ERCP) due to suspected BDS. Methods: A total of 213 patients who were suspected of having BDS were included in this retrospective study. The patients were divided into two groups: Group A in which BDS was visualized by ERCP; and Group B in which BDS was demonstrated only by IDUS. Comparison between the groups was carried out. Results: ERCP successfully visualized BDS in 166 patients. Forty‐seven patients underwent IDUS, which revealed BDS and biliary sludge in 12 and eight patients, respectively. The diameter of the largest stone was 13 ± 6 mm in Group A and 5 ± 1 mm in Group B (P < 0.001). The sensitivity, specificity, and accuracy of ERCP in the diagnosis of BDS were 93%, 100%, and 94%, respectively. The sensitivity was influenced by the size of BDS: 100% in cases of stones ≥8 mm in size, but 74% in those with stones <8 mm. In cases with stones <8 mm, the sensitivity was significantly affected by the bile duct diameter (≥12 mm vs <12 mm, P < 0.05). Conclusion: When ERCP fails to visualize stones in patients with suspected BDS, IDUS is recommended, especially in those with a bile duct ≥12 mm in diameter.