Dilation of both pancreatic duct and the common bile duct on computed tomography and magnetic resonance imaging scans in patients with or without obstructive jaundice

Biliary Duct Dilatation: AJR Expert Panel Narrative Review

Biliary duct dilatation is a common incidental finding in practice, but it is unlikely to indicate biliary obstruction in the absence of clinical symptoms or elevated levels on liver function tests (LFTs). However, the clinical presentation may be nonspecific, and LFTs may either be unavailable or difficult to interpret. The goal of this AJR Expert Panel Narrative Review is to highlight a series of topics fundamental to the management of biliary duct dilatation, providing consensus recommendations in a question-and-answer format. We start by covering a basic approach to interpreting LFT results, the strengths and weaknesses of the biliary imaging modalities, and how and where to measure the extrahepatic bile duct. Next, we define the criteria for biliary duct dilatation, including patients with prior cholecystectomy and advanced age, and discuss when and whether biliary duct dilatation can be attributed to papillary stenosis or sphincter of Oddi dysfunction. Subsequently, we discuss two conditions in which the duct is pathologically dilated but not obstructed: congenital cystic dilatation (i.e., choledochal cyst) and intraductal papillary neoplasm of the bile duct. Finally, we provide guidance regarding when to recommend obtaining additional imaging or testing, such as endoscopic ultrasound or ERCP, and include a discussion of future directions in biliary imaging.

Clinical Significance and Resource Burden of Double Duct Sign in Non-jaundiced Patients

Aim The study aims to determine the incidence of malignancy at presentation and subsequent risk of malignancy (at 12 months follow-up) in a cohort of patients with double duct sign (DDS) on cross-sectional imaging but no visible stigmata of jaundice. The study also correlates malignancy with liver enzyme dysfunction and estimates the resource burden incurred during the investigation of these patients. Methods A search for the key term "double duct sign" was undertaken in the radiological database of a tertiary hepatopancreatobiliary (HPB) centre between March 2017 and March 2022. Radiological reports, clinic letters, blood results, and multidisciplinary team meeting (MDT) outcomes were reviewed during this period and at one year. The national tariff payment system was reviewed to identify tariffs for different investigations required for the cohort and to calculate the total cost incurred. Results Ninety-seven patients with DDS were identified. Sixty-four patients (66%) had a normal bilirubin (0-21 µmol/L) at presentation and were included in the analysis. Seven patients (10.9%) were diagnosed with malignant peri-ampullary tumours, and 21 (32.8%) were diagnosed with benign diseases. In 34 patients (53%) with DDS, the underlying cause remained uncharacterised. Most patients had mild abnormalities of liver enzymes, but two patients (4.3%) were diagnosed with malignant peri-ampullary tumours despite having normal serological values. Patients who had a benign diagnosis and/or who had cancer excluded without a definitive diagnosis did not go on to develop a malignancy at 12 months follow-up. However, in those patients where the underlying aetiology could not be characterised, extended surveillance was required with a total of 80 MDT discussions and multiple surveillance scans (103 CT and 65 MRI scans). Twenty-six patients underwent endoscopic ultrasound (EUS) with three patients requiring more than one EUS examination (29 investigations in total). The cost of these investigations was £38,926.89. Conclusion This study confirms that DDS even in patients without clinical jaundice or with normal liver enzymes requires careful investigation to exclude malignancy despite the resource burden this entails. This supports previously reported results in the literature, and despite the increased use of cross-sectional imaging, DDS remains a clinically significant finding. Large cohort risk stratification studies would be useful to determine clinical urgency and allow the appropriate allocation of resources.

Incidental double duct sign: Should we be worried? Results from a long-term follow-up study

Backgrounds/Aims

Double duct sign (DDS) (dilated common bile and pancreatic duct) is synonymous with pancreatic head/peri-ampullary tumor (PHPAT). There is limited evidence on whether incidental DDS (I-DDS) is associated with an increased risk of malignancy. This study aimed to evaluate 5-year outcomes of I-DDS.

Methods

Patients were categorized according to their risk of malignancy. 'Low-risk' patients, including those with I-DDS between 2010 and 2015, were analyzed in this study. The primary outcome was incidence of PHPAT within five years of identification of DDS. Histology results from endoscopic ultrasound-guided biopsy were considered diagnostic. Secondary outcomes were incidence of benign causes, extent of follow-up investigations, and clinical indicators of malignancy in patients with DDS.

Results

Among 103 patients with DDS, 20 had I-DDS. Subsequent follow-up of these 20 patients found no patient with PHPAT, two (10%) patients with chronic pancreatitis, and 18 (90%) patients with no cause found. The median follow-up duration for 'low-risk' patients was 7.3 years (range, 6-11 years). The mean number of follow-up investigations per patient was two (range, 0-9). Investigations included computed tomography (n = 27), magnetic resonance cholangiopancreatography (n = 23), endoscopy (n = 16), and ultrasound (n = 14). Patients with jaundice were more likely to have malignancy (p < 0.01). Those with abdominal pain were more likely to have a benign cause (p < 0.01). Hyperbilirubinemia and/or deranged liver enzymes and raised CA19-9 were more likely to be associated with PHPAT (p < 0.01).

Conclusions

Patients with I-DDS have a low risk of developing PHPAT within five years.

Neuroendocrine Tumor of the Ampulla of Vater: A Case Report

Neuroendocrine tumors (NETs) of the ampulla of Vater are extremely rare. Here, we discuss the clinical presentation, diagnostic challenges, and treatment options of a recently experienced case of NET of the ampulla of Vater in light of the literature. A 56-year-old woman presented with recurrent upper abdominal pain. Ultrasonography (USG) of the whole abdomen showed multiple gallstones along with a dilated common bile duct (CBD). For evaluating the dilated CBD, a magnetic resonance cholangiopancreatography was performed, which revealed the double-duct sign. Subsequently, an upper gastrointestinal endoscopy showed a bulged-out ampulla of the Vater. Biopsy and histopathological examination of the growth yielded the diagnosis of adenocarcinoma. A Whipple procedure was performed. Macroscopically, a 2 cm growth was noted involving the ampulla of Vater, and microscopic findings were consistent with a well-differentiated NET, grade 1 (low grade). The diagnosis was further confirmed by immunohistochemical staining (pan-cytokeratin positive, synaptophysin positive, and focally chromogranin positive). Her postoperative course was uneventful except for delayed gastric emptying. A detailed evaluation and a high index of suspicion are required for the diagnosis of this rare tumor. Treatment is relatively easier after a proper diagnosis.

Clinical characteristics, risk factors and diagnostic outcomes of patients presented with indeterminate biliary stricture: A multicenter study

Background and aim

Indeterminate biliary stricture (IBS) is a frequently encountered clinical problem. In this study, we aimed to highlight the clinical characteristics, risk factors and diagnostic outcomes of patients presented with indeterminate biliary stricture.

Method

A Retrospective multicenter study included all patients diagnosed with IBS in the participating centers between 2017 and 2021. Data regarding IBS such as presentations, patient characteristics, diagnostic and therapeutic modalities were collected from the patients' records and then were analyzed.

Results

Data of 315 patients with IBS were retrospectively collected from 7 medical centers with mean age: 62.6 ± 11 years, females: 40.3% and smokers: 44.8%. For diagnosing stricture; Magnetic resonance imaging/Magnetic resonance cholangiopancreatography (MRI/MRCP) was the most frequently requested imaging modality in all patients, Contrast enhanced computerized tomography (CECT) in 85% and endoscopic ultrasound (EUS) in 23.8%. Tissue diagnosis of cholangiocarcinoma was achieved in 14% only. The used therapeutic modalities were endoscopic retrograde cholangiopancreatography (ERCP)/stenting in 70.5%, percutaneous trans-hepatic biliary drainage (PTD): 17.8%, EUS guided drainage: 0.3%, and surgical resection in 8%. The most frequent type of strictures was distal stricture in 181 patients, perihilar in 128 and intrahepatic in 6. Distal strictures had significant male predominance, with higher role for EUS for diagnosis and higher role for ERCP/stenting for drainage, while in the perihilar strictures, there was higher role for CECT and MRI/MRCP for diagnosis and more frequent use of PTD for drainage.

Conclusion

Indeterminate biliary stricture is a challenging clinical problem with lack of tissue diagnosis in most of cases mandates an urgent consensus diagnostic and treatment guidelines.

Biliary Tree Diagnostics: Advances in Endoscopic Imaging and Tissue Sampling

The diagnostic approach to the biliary tree disorders can be challenging, especially for biliary strictures. Albeit the great diagnostic impact of endoscopic retrograde cholangiopancreatography (ERCP) which allows one to obtain fluoroscopic imaging and tissue sampling through brush cytology and/or forceps biopsy, a considerable proportion of cases remain indeterminate, leading to the risk of under/over treated patients. In the last two decades, several endoscopic techniques have been introduced in clinical practice, shrinking cases of uncertainties and improving diagnostic accuracy. The aim of this review is to discuss recent advances and emerging technologies applied to the management of biliary tree disorders through peroral endoscopy procedures.

Adenomatous neoplasia in the papilla of Vater endoscopic and/or surgical resection?

BACKGROUND

Adenomatous neoplasia in the papilla of Vater needs to be resected in order not to progress. It can be challenging to distinguish between early ampullary malignant lesions and non-invasive adenomas, due to the overlap in symptoms and radiological findings. This retrospective study describes the different findings and treatment decisions taken prior to endoscopic and/or surgical resection of ampullary adenomatous lesions.

MATERIALS AND METHODS

Patients treated with endoscopic and/or surgical resection for suspected or verified ampullary adenomatous neoplasia, between January 2006 and July 2018, where pre-interventional cross-sectional imaging could not discern an obvious invasive, malignant tumor, were included. Findings were compared against the final diagnosis of the histopathological analysis on the resected specimen.

RESULTS

In total, 172 met the inclusion criteria. Patients were treated with either surgical resection (n = 96), endoscopic papillectomy (EP) (n = 55) or both (n = 21). The final diagnosis was in 48% ampullary adenocarcinoma, and the remaining had either ampullary adenoma (38%) or non-neoplastic lesions (14%). In patients where symptoms and cross-sectional imaging were suspicious for malignancy, but with no tissue samples that confirmed neoplasia prior to surgical resection, only 47% had adenocarcinoma. The remaining had either adenoma (9%) or non-neoplastic lesions (44%). Adenocarcinoma was revealed in 27% of the patients where endoscopic biopsies had shown adenoma. Patients with adenoma, treated with EP, were cured in 59%. However, 28% were after EP sent for further surgery due to ductal invasion or a finding of adenocarcinoma.

CONCLUSIONS

In patients with a suspicion of ampullary neoplasia on imaging, attempts should be made to get endoscopic tissue samples before deciding on a treatment strategy. If biopsies show ampullary adenoma, patients should be considered for EP, unless there are clear radiologic or endoscopic signs of malignancy. Patients with adenocarcinoma on endoscopic biopsies should undergo surgical resection.

Diagnostic performance of EUS in non-jaundiced patients with an incidental finding of double duct sign on cross-sectional imaging: A systematic review and meta-analysis

BACKGROUND/OBJECTIVES

Dilatation of the pancreatic duct and common bile duct, known as double duct sign (DDS), suggests sinister pathology at the periampullary region. Non-jaundiced patients with incidental DDS and otherwise normal cross-sectional imaging present a diagnostic dilemma to the multidisciplinary team (MDT). The primary aim of this review was to assess the diagnostic yield of endoscopic ultrasound (EUS) in detecting causal pathology in this patient population.

METHODS

A systematic literature search (Medline, EMBASE, Google Scholar, Cochrane database and PROSPERO) was performed to identify original studies that reported EUS findings in patients with incidental DDS. Primary outcome was detection of a periampullary tumour. Secondary outcome was detection of benign causal pathology. Meta-analysis was used to calculate an absolute measure (pooled proportion) of pathology detection.

RESULTS

Four studies (177 patients) were included. EUS detection rate for a periampullary tumour was 5% (95% CI, 0-10%) including both adenocarcinomas and adenomas. EUS detection rate for benign causal pathology was 22% (95% CI, 10-34%), the most common being chronic pancreatitis CONCLUSION: Non-jaundiced patients with incidental DDS on cross-sectional imaging have a 5% risk of a periampullary tumour that can be detected by EUS.

What should be known prior to performing EUS?

Direct referral of patients for EUS – instead of preprocedural consultation with the endosonographer – has become standard practice (like for other endoscopic procedures) as it is time- and cost-effective. To ensure appropriate indications and safe examinations, the endosonographer should carefully consider what information is needed before accepting the referral. This includes important clinical data regarding relevant comorbidities, the fitness of the patient to consent and undergo the procedure, and the anticoagulation status. In addition, relevant findings from other imaging methods to clarify the clinical question may be necessary. Appropriate knowledge and management of the patients’ anticoagulation and antiplatelet therapy, antibiotic prophylaxis, and sedation issues can avoid unnecessary delays and unsafe procedures. Insisting on optimal preparation, appropriate indications, and clear clinical referral questions will increase the quality of the outcomes of EUS. In this paper, important practical issues regarding EUS preparations are raised and discussed from different points of view.

Indeterminate biliary strictures: a simplified approach

Pre-operative evaluation of biliary strictures remains challenging. The dilemma that exists is how to balance the risk of failing to detect malignancy and the potential morbidity caused by unnecessary surgery in patients with benign etiologies. With emerging novel diagnostic modalities, this study aims to assess the efficacy of diagnostic techniques and facilitate a clinical approach to indeterminate biliary strictures. Areas covered: Conventional imaging modalities are crucial in identifying the location of a stricture and are helpful for choosing further diagnostic modalities. Utilization of endoscopic techniques, including endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic ultrasound (EUS), is key in establishing a diagnosis. The emergence of novel diagnostic modalities, such as fluorescence in-situ hybridization (FISH), peroral cholangioscopy (POC), intraductal endoscopic ultrasound (IDUS) and confocal laser endomicroscopy (CLE), enhance the diagnostic yield in the evaluation of indeterminate biliary strictures. Expert commentary: More reliable and validated visual criteria for differentiating malignancy from benign biliary conditions, utilizing advanced imaging modalities such as POC and CLE, need to be established. It is of significance to further evaluate these novel diagnostic modalities through ongoing trials and to develop a diagnostic algorithm that reconciles cost-effectiveness with diagnostic accuracy.

Simultaneous Courvoisier’s and double duct signs

Presence of Courvoisier’s or double duct signs in a jaundiced patient is suggestive of malignant obstruction of the pancreaticobiliary ductal system. The oncologic impact of the simultaneous occurrence of these signs on the survival of patients with periampullary cancer is unknown. We report a case of obstructive jaundice secondary to an ampullary cancer demonstrating the Courvoisier’s sign on clinical examination and a double duct sign on imaging. The patient underwent a pancreaticoduodenectomy which confirmed an ampullary adenocarcinoma.

Diagnostic Value and Interreader Agreement of the Pancreaticolienal Gap in Pancreatic Cancer on MDCT

OBJECTIVE

The aim of this retrospective study was to evaluate the diagnostic value and measure interreader agreement of the pancreaticolienal gap (PLG) in the assessment of imaging features of pancreatic carcinoma (PC) on contrast-enhanced multi-detector computed tomography (CE-MDCT).

MATERIALS AND METHODS

CE-MDCT studies in the portal venous phase were retrospectively reviewed for 66 patients with PC. The age- and gender-matched control group comprised 103 healthy individuals. Three radiologists with different levels of experience independently measured the PLG (the minimum distance of the pancreatic tail to the nearest border of the spleen) in the axial plane. The interreader agreement of the PLG and the receiver operating characteristic (ROC) curve was used to calculate the accuracy of the technique.

RESULTS

While the control group (n = 103) showed a median PLG of 3 mm (Range: 0 - 39mm) the PC patients had a significantly larger PLG of 15mm (Range: 0 - 53mm)(p < 0.0001). A ROC curve demonstrated a cutoff-value of >12 mm for PC, with a sensitivity of 58.2% (95% CI = 45.5-70.1), specificity of 84.0% (95% CI = 75.6-90.4) and an area under the ROC curve of 0.714 (95% CI = 0.641 to 0.780). The mean interreader agreement showed correlation coefficient r of 0.9159. The extent of the PLG did not correlate with tumor stage but did correlate with pancreatic density (fatty involution) and age, the density decreased by 4.1 HU and the PLG increased by 0.8 mm within every 10 y.

CONCLUSION

The significant interreader agreement supports the use of the PLG as a characterizing feature of pancreatic cancer independent of the tumor stage on an axial plane. The increase in the PLG with age may represent physiological atrophy of the pancreatic tail.

Advanced endoscopic imaging of indeterminate biliary strictures

Endoscopic evaluation of indeterminate biliary strictures (IDBSs) has evolved considerably since the development of flexible fiberoptic endoscopes over 50 years ago. Endoscopic retrograde cholangiography pancreatography (ERCP) was introduced nearly a decade later and has since become the mainstay of therapy for relieving obstruction of the biliary tract. However, longstanding methods of ERCP-guided tissue acquisition (i.e., biliary brushings for cytology and intraductal forceps biopsy for histology) have demonstrated disappointing performance characteristics in distinguishing malignant from benign etiologies of IDBSs. The limitations of these methods have thus helped drive the search for novel techniques to enhance the evaluation of IDBSs and thereby improve diagnosis and clinical care. These modalities include, but are not limited to, endoscopic ultrasound, intraductal ultrasound, cholangioscopy, confocal endomicroscopy, and optical coherence tomography. In this review, we discuss established and emerging options in the evaluation of IDBSs.

Double-Duct Sign in the Clinical Context

OBJECTIVES

Double-duct sign (combined dilatation of the common bile duct and pancreatic duct) is an infrequently encountered finding in cross-sectional radiological imaging of the pancreatobiliary system. This sign is commonly deemed to signify on ominous pathology and suggests the presence of pancreatic or biliary malignancy.

METHODS

We aim to correlate double-duct sign discovered on magnetic resonance cholangiopancreatogram (MRCP) in the clinical context. We retrospectively analyzed MRCP database over a period of 4 years, January 2010 to December 2013. Follow-up information was available for a median of 27 months (range, 12-42 months)

RESULTS

The commonest cause of double-duct sign was choledocholithiasis followed closely by pancreatobiliary malignancy. Patients with jaundice in the context of double-duct sign had a higher incidence of malignancy (48%). None of the anicteric patients were found to have malignancy (P = 0.002).

CONCLUSIONS

In patients with MRCP evidence of double-duct sign, the absence of jaundice makes a malignant etiology unlikely. Conversely, in jaundiced patients, a malignant cause is much more likely. Figures from larger series are needed to support this conclusion.

Biliary strictures: diagnostic considerations and approach

Biliary strictures present a diagnostic challenge, especially when no etiology can be ascertained after laboratory evaluation, abdominal imaging and endoscopic retrograde cholangiopancreatography (ERCP) sampling. These strictures were traditionally classified as indeterminate strictures, although with advances in endoscopic techniques and better understanding of hepato-biliary pathology, more are being correctly diagnosed. The implications of missing a malignancy in patients with biliary strictures—and hence delaying surgery—are grave but a significant number of patients (up to 20%) undergoing surgery for suspected biliary malignancy can have benign pathology. The diagnostic approach to these patients involves detailed history and physical examination and depends on the presence or absence of jaundice, level of obstruction, and presence or absence of a mass lesion. While abdominal imaging helps to find the level of obstruction and provides a ‘road map' for further endoscopic investigations, tissue diagnosis is usually needed to make decisions on management. Initially ERCP was the only modality to investigate these strictures but now, with the development of endoscopic ultrasound with fine needle aspiration and the availability of newer techniques such as intraductal ultrasound, single-operator cholangioscopy and confocal laser endomicroscopy, the diagnostic approach to biliary strictures has changed significantly. In this review, we will focus on the decision-making process for patients with biliary strictures and discuss the key decision points that should dictate further diagnostic investigations at each step.

Double-duct sign in the era of endoscopic ultrasound: the prevalence of occult pancreaticobiliary malignancy

BACKGROUND AND AIM

Simultaneous dilatation of the common bile duct and pancreatic duct, "double-duct sign" (DDS), is an ominous finding concerning for pancreaticobiliary malignancy. Little evidence exists to guide the initial evaluation and subsequent follow-up for patients with DDS in the absence of jaundice or focal mass noted on computed tomography (CT)/ magnetic resonance imaging (MRI). Endoscopic ultrasound (EUS) is often recommended in the evaluation of such patients, however, the prevalence of malignancy remains unclear. We sought to determine the prevalence of pancreaticobiliary neoplasm in this patient group on initial EUS evaluation and on subsequent clinical follow-up.

METHODS

We performed a retrospective analysis of a prospective database at a tertiary-care academic medical center between 2010 and 2012. Eighty-two patients were identified who underwent EUS evaluation for DDS without evidence of a mass on CT/MRI and without jaundice.

RESULTS

Sixty-eight of 82 patients had confirmed DDS on EUS with biductal dilation. Six (9 %) of 68 patients were found to have a mass lesion on EUS. In these patients, final diagnoses were pancreatic carcinoma (n = 4), ampullary carcinoma (n = 1) and ampullary adenoma (n = 1). In the 62 patients without evidence of a focal mass on initial EUS, the most common diagnoses were benign ductal dilation (n = 42), chronic pancreatitis (n = 9) and choledocholithiasis (n = 8). Fifty-eight (94 %) of 62 patients had documented median follow-up of 13 months, and none developed subsequent evidence of previously unrecognized malignancy.

CONCLUSIONS

The presence of double-duct sign on EUS in patients without jaundice or mass lesion on CT/MRI is most frequently associated with benign conditions. When a mass is not detected on EUS, subsequent evidence of malignancy is unlikely.

Endoscopic ultrasound in patients with normal liver blood tests and unexplained dilatation of common bile duct and or pancreatic duct

OBJECTIVE

To determine the yield of endoscopic ultrasound (EUS) in the investigation of patients with normal liver function tests (LFTs) and unexplained dilatation of common bile duct (CBD) and/or pancreatic duct (PD), following CT and/or magnetic resonance cholangiopancreatography.

MATERIALS AND METHODS

Consecutive patients undergoing linear EUS between January 2007 and August 2011 for the indication of dilated CBD and/or PD, normal LFT, and nondiagnostic cross-sectional imaging formed the study group. The study was performed as a retrospective analysis of prospectively collected data.

RESULTS

During the study period, 83 patients (CBD and PD dilatation n = 38, PD dilatation n = 5, CBD dilatation n = 40) met the inclusion criteria and underwent EUS. Five (13.1%) of the CBD and PD groups had a new finding, which in one (2.6%) case was causal. In this group, men were significantly more likely to have a new finding (p = 0.012). Eight (20%) of the CBD group had a new finding, which in seven (17.5%) cases was causal. In the CBD group, cholecystectomy was significantly (p = 0.005) more common in those without a finding. Three (60%) of the PD group had a finding on EUS, all of which were causal, including a case of pancreatic malignancy.

CONCLUSION

There is a significant yield from EUS in individuals with isolated PD dilatation and isolated CBD dilatation. Previous cholecystectomy is significantly associated with a negative EUS in the group with isolated CBD dilatation. The yield in those with CBD and PD dilatation was low and a finding was more likely in males.