Cholangiocarcinoma and intraductal sonography

Diagnosis of Cholangiocarcinoma

Cholangiocarcinoma (CCA), a tumor of the bile duct epithelium, is increasing in incidence. CCA remains a highly fatal malignancy because early diagnosis is difficult. Based on its anatomical location, CCA can be categorized into the following three groups: perihilar, intrahepatic, and extrahepatic. Patients with CCA complain of asymptomatic jaundice, weight loss, and right upper quadrant abdominal discomfort. Imaging modalities, including transabdominal ultrasound, computed tomography, and magnetic resonance imaging, play an important role in detecting tumors as well as guiding biopsy procedures and staging workups in CCA. Characteristically, extrahepatic CCA shows abrupt changes in ductal diameter with upstream ductal dilation. Endoscopic ultrasound (EUS) and endoscopic retrograde cholangiopancreatography (ERCP) are recommended as the next step in the evaluation of extrahepatic CCA. Tissue is obtained through EUS-FNA or ERCP (biopsy, brush cytology), and therapeutic intervention (such as stent insertion) is performed with ERCP. Moreover, several serum tumor markers (carbohydrate antigen 19-9 and carcinoembryonic antigen) can be useful in diagnosing CCA in some patients.

Novel biliopancreatic duct endoscope combining optical coherence tomography with intraductal US for exploring the bile duct: a diagnostic study in a porcine model

BACKGROUND AND AIMS

Existing biliopancreatic duct endoscopy is deficient in the examination of early biliary and pancreatic tumors. This study aimed to evaluate the usefulness and feasibility of a novel ultrafine, separable, biliopancreatic duct endoscopy device with dual modalities of intraductal US (IDUS) and optical coherence tomography (OCT) for the in vivo assessment of the biliopancreatic duct system during ERCP.

METHODS

Five Bama miniature pigs were selected to probe their common bile duct and branches by using this novel equipment during ERCP. The feasibility of the procedure was evaluated by clear, clinically interpretable images obtained by using spiral scanning with the pull-back method. The clinical usefulness of the novel product was evaluated by postoperative choledochoscopy and assessment of the animal's general condition.

RESULTS

One hundred forty-one pairs of images from 5 Bama miniature pigs were acquired. Visualization of the bile duct using both OCT and IDUS was characterized by a differentiated 3-layer architecture, whereas IDUS had poor clarity when compared with OCT. Postoperative choledochoscopy showed no local lesion in the bile duct wall, and the general condition of animals was normal.

CONCLUSIONS

This prospective evaluation indicated the feasibility and potential clinical value of the novel, ultrafine, separable biliopancreatic duct endoscopy device. The fusion of the 2 imaging modalities can shed light on the early diagnosis of biliary and pancreatic tumors. Further studies will be carried out to establish diagnosis criteria with the dual-modality imaging using an animal pathologic model and a human clinical study.

The Role of Endoscopy in the Diagnosis and Management of Cholangiocarcinoma

Cholangiocarcinomas (CCAs) are associated with poor overall survival, and majority of the tumors are unresectable at the time of diagnosis. Early diagnosis at a resectable stage is essential for improved outcomes. Noninvasive imaging plays an important role in evaluating patients with biliary obstruction, but is limited due to the lack of tissue sampling and in many cases due to the absence of a mass, especially for extrahepatic CCAs. Endoscopic diagnosis is needed in majority of patients with CCA and the diagnostic yield depends on the tumor location as well as the expertise and experience of the endoscopist. Endoscopic retrograde cholangiopancreatography and endoscopic ultrasound remain the most common endoscopic diagnostic tools although newer technologies including fluorescence in situ hybridization, single-operator cholangioscopy, confocal laser endomicroscopy, and intraductal ultrasound are being increasing used. Traditionally, the role of endoscopy has been mainly palliative and limited to biliary drainage in patients with obstructive jaundice, however, newer treatment options like photodynamic therapy and radiofrequency ablation have shown promise toward improved patient survival. Multidisciplinary approach that involves medical oncology, gastroenterology, radiology, and surgical oncology teams is imperative for improved outcomes. In this review, we will first review the diagnostic approach to CCAs including imaging and endoscopic methods followed by a discussion of different endoscopic techniques in management of patients after a diagnosis of CCA.

Preoperative evaluation of the longitudinal extent of borderline resectable hilar cholangiocarcinoma by intraductal ultrasonography

BACKGROUND AND AIM

In patients with hilar cholangiocarcinoma (HC), longitudinal tumor extent is important for curative resection. The purpose of this study was to evaluate the longitudinal extents of HC using transpapillary intraductal ultrasonography (IDUS) for optimal surgical planning.

METHODS

From July 2006 to April 2010, a total of 42 patients with borderline resectable HC were enrolled at Samsung Medical Center, a tertiary referral hospital in Seoul, Korea. All patients were evaluated using multi-detector computed tomography (MDCT), endoscopic retrograde cholangiopancreatography (ERCP) and IDUS. The new modified Bismuth Type (MBT) classification, in which the traditional Bismuth type IV stage is divided into stages IVa and IVb, was used to determine whether the tumor invaded the left lateral section. Among the subtypes of HC, the periductal infiltrative type (PDI) and intraductal papillary neoplasm of the bile duct (IPN-B) were compared. The accuracies of CT, ERCP, and IDUS were assessed through comparison with the postoperative histology findings.

RESULTS

A total of 42 patients were prospectively enrolled, and the tumor extent could be assessed histologically in 30 patients. The accuracies of CT, ERCP, and IDUS were 66.6%, 60%, and 90%, respectively. The accuracy of IDUS was 85.7% in 21 patients with PDI and 100% in nine patients with IPN-B.

CONCLUSIONS

Hilar cholangiocarcinoma staging based on IDUS findings was highly accurate. We therefore highly recommend using IDUS for optimal surgical planning in patients with borderline resectable HC.

Intraductal ultrasonography combined with percutaneous transhepatic cholangioscopy for the preoperative evaluation of longitudinal tumor extent in hilar cholangiocarcinoma

BACKGROUND AND AIM

In hilar cholangiocarcinoma, an accurate assessment of preoperative resectability is important to optimize surgical resection. We investigated the accuracy of the combination of intraductal ultrasonography (IDUS) and percutaneous transhepatic cholangioscopy (PTCS) for evaluating longitudinal extent in hilar cholangiocarcinoma.

METHODS

Patients diagnosed with hilar cholangiocarcinoma underwent multidetector computed tomography (MDCT) and magnetic resonance cholangiography (MRC) for tumor staging and Bismuth type. Percutaneous transhepatic biliary drainage was performed at the left or right bile duct of the liver section that was anticipated to be preserved in the surgical treatment. After tract dilation, PTCS with cholangioscope-directed biopsy and IDUS were sequentially performed to evaluate Bismuth type. Surgical treatment was executed according to tumor staging and longitudinal tumor extent. Postoperative histological Bismuth types were compared to preoperative Bismuth types based on MDCT, MRC, PTCS with biopsy, and IDUS.

RESULTS

From June 2006 to November 2008, 25 patients with hilar cholangiocarcinoma were enrolled, with 20 of these patients evaluable. The accuracy of MDCT, MRC, PTCS with biopsy, and IDUS for the evaluation of Bismuth type was 80%, 84.2%, 90%, and 85.0%, respectively, in 20 patients, and 82.4%, 82.4%, 94.1%, and 88.2%, respectively, in 18 patients with Bismuth type IIIa, IIIb, or IV cancer. The accuracy of the combination of IDUS and PTCS with biopsy was 95% in 20 patients, and 100% in 18 with Bismuth type IIIa, IIIb, or IV cancer.

CONCLUSIONS

The combination of IDUS and PTCS with biopsy was highly accurate for assessing Bismuth type and may help in the identification of an optimal surgical plan for the treatment of hilar cholangiocarcinoma, especially in Bismuth type IIIa, IIIb, or IV.

Differential diagnosis and treatment of biliary strictures

Biliary tract strictures present both diagnostic and therapeutic challenges to clinicians. Advances in imaging and endoscopic techniques have improved our ability to differentiate between benign and malignant lesions. Intraductal ultrasonography (IDUS), using an endoscopic approach, has the potential to aid in separating benign and malignant biliary lesions. In a series of 93 patients, a majority of whom had cancer, we found that IDUS had a sensitivity and specificity of 89.7% and 84%, respectively, for diagnosing biliary strictures. However, benign strictures associated with untreated autoimmune pancreatitis and/or the intrapancreatic portion of the distal common bile duct could not be easily distinguished from malignant strictures. Direct visualization of biliary mucosa using a percutaneous transhepatic endoscopic approach also helps separate benign from malignant biliary strictures. Further, the ability to obtain multiple directed biopsies using a percutaneous approach also increases diagnostic accuracy. A final advantage of the percutaneous approach is that once a suitable sized tract has been established, biliary strictures and stents can be placed. IDUS and percutaneous biliary endoscopy are promising new modalities for the diagnosis and treatment of biliary strictures.

Inflammation and carcinogenesis of the biliary tract: update on endoscopic treatment

Both diagnosis and treatment of cholangiocarcinoma are suboptimal. From the former standpoint, fluorescence in situ hybridization, direct cholangioscopy, endocystoscopy, and optical coherence tomography are just a few of the myriad technologies being studied or employed to improve diagnostic yield. From the latter standpoint, most series suggest that fewer than 1 third of patients are resectable for cure, although liver transplantation has increasingly been used in a subset of cholangiocarcinoma patients with extrahepatic disease. Palliation has included chemotherapy which is of dubious value in most series. Instead, a majority of therapies have addressed mechanisms to improve biliary drainage to delay and preclude hepatic failure and minimize the risk of cholangitis. Although the latter has been accomplished with surgery and attempted with external beam irradiation and brachytherapy, percutaneous and/or endoscopic drainage are the most commonly employed methods in widespread use. There are prospective, randomized studies that suggest that bilateral stenting is associated with improved outcomes in bifurcation lesions if plastic stents are placed, that percutaneous transhepatic biliary drainage is more successful than endoscopic stenting in Klatskin tumors, that self-expandable biliary stents have prolonged patency compared with plastic prostheses, and that, if approached with computed tomography and magnetic resonance imaging guidance to preclude contamination of the contralateral undrained system, outcomes are comparable in patients treated with unilateral as opposed to bilateral self-expandable metal stents. There is a single prospective, randomized study suggesting that patients treated with endoscopic or percutaneous stenting in conjunction with photodynamic therapy have prolonged survival compared with stent placement alone.

Evaluation of normal bile duct and cholangitis by intraductal ultrasonography

BACKGROUND

The intraductal ultrasonographic findings of normal bile duct and cholangitis were examined.

METHODS

We studied 9 autopsy cases and evaluated the clinical records of 76 patients who had been subjected to papillotomy for bile duct stones removal retrospectively.

RESULT

In vitro study: Under a low pressure, the bile duct wall was thick, and the inner surface and outer contour were irregular. The wall became thinner, and the inner surface and outer contour became smooth as the pressure was increased. The thickness was 0.68 +/- 0.12 mm (mean +/- SD) all along the duct at all pressure, and 0.55 +/- 0.12 mm at a pressure above 15 cm H(2)O. The internal echo was homogenous regardless of the internal pressure used. In vivo study: We could evaluate in 70 patients (92.1%). The wall was 1.30 +/- 0.77 mm thick. There was no relationship between the severity of cholangitis and the wall thickness. The irregular inner surface, heterogeneous internal echo, and irregular outer contour correlated with the severity of cholangitis.

CONCLUSION

The normal bile duct wall was between 0.31 and 0.79 mm thick, the inner and outer surfaces were smooth, and internal echo was homogenous. An irregular inner surface, heterogeneous internal echo and an irregular outer contour were important findings of severe cholangitis.

EUS-guided FNA of proximal biliary strictures after negative ERCP brush cytology results

BACKGROUND

Accurate nonoperative diagnosis of proximal biliary strictures (PBSs) is often difficult.

OBJECTIVE

To report our experience with EUS-guided FNA (EUS-FNA) of PBSs following negative or unsuccessful results with brush cytology during ERCP.

DESIGN

Retrospective cohort study.

SETTING

Single, tertiary referral hospital in Indianapolis, Indiana.

PATIENTS

Consecutive subjects from January 2001 to November 2004 who underwent EUS-FNA of a PBS documented by ERCP.

INTERVENTIONS

EUS-FNA of PBS.

MAIN OUTCOME MEASURES

Performance of EUS-FNA, with the final diagnosis determined by surgical pathology study or the results of EUS-FNA and follow-up.

RESULTS

A total of 291 biliary strictures undergoing EUS were identified. Of these, 26 (9%) had PBSs and 2 were excluded. EUS-FNA was not attempted in 1 because no mass was visualized. The second had a PBS seen on magnetic resonance cholangiopancreatography, but no ERCP was performed. Twenty-four patients (14 men; mean age, 68 years) underwent EUS-FNA of a PBS following ERCP brush cytology studies that were either negative/nondiagnostic (20) or unable to be performed (4). EUS visualized a mass in 23 (96%) patients, including 13 in whom previous imaging detected no lesion. EUS-FNA (median, 4 passes; range, 1-11) demonstrated malignancy in 17 of 24 (71%) patients with findings showing adenocarcinoma (15), lymphoma (2), atypical cytology (3), or benign cells (4). No complications were noted. Pathology results from 8 of 24 (33%) patients who underwent surgery showed hilar cholangiocarcinoma (6), gallbladder cancer (1), and a benign, inflammatory stricture (1). The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of EUS-FNA were 77% (95% confidence interval [CI], 54%-92%), 100% (95% CI, 15%-100%), 100% (95% CI, 83%-100%), 29% (95% CI, 4%-71%), and 79% (95% CI, 58%-93%), respectively.

LIMITATIONS

Histopathologic correlation of EUS-FNA findings was limited to 8 of 24 (33%) patients who underwent surgery.

CONCLUSIONS

EUS-FNA is a sensitive method for the diagnosis of PBSs following negative results or unsuccessful ERCP brush cytology. The low negative predictive value does not permit reliable exclusion of malignancy following a negative biopsy.