Differentiation of infiltrative cholangiocarcinoma from benign common bile duct stricture using three-dimensional dynamic contrast-enhanced MRI with MRCP

MicroRNAs as Bile-based biomarkers in pancreaticobiliary cancers (MIRABILE): a cohort study

BACKGROUND

Biliary obstruction can be due to both malignant and benign pancreaticobiliary disease. Currently, there are no biomarkers that can accurately help make this distinction. MicroRNAs (miRNAs) are stable molecules in tissue and biofluids that are commonly deregulated in cancer. The MIRABILE study aimed to identify miRNAs in bile that can differentiate malignant from benign pancreaticobiliary disease.

MATERIALS AND METHODS

There were 111 patients recruited prospectively at endoscopic retrograde cholangiopancreatography (ERCP) or percutaneous transhepatic cholangiography (PTC) for obstructive jaundice, and bile was aspirated for cell-free RNA (cfRNA) extraction and analysis. In a discovery cohort of 78 patients (27 with pancreatic ductal adenocarcinoma (PDAC), 14 cholangiocarcinoma (CCA), 37 benign disease), cfRNA was subjected to small-RNA sequencing. LASSO regression was used to define bile miRNA signatures, and NormFinder to identify endogenous controls. In a second cohort of 87 patients (34 PDAC, 14 CCA, 39 benign disease), RT-qPCR was used for validation.

RESULTS

LASSO regression identified 14 differentially-expressed bile miRNAs of which 6 were selected for validation. When comparing malignant and benign pancreaticobiliary disease, bile miR-340 and miR-182 were validated and significantly differentially expressed ( P <0.05 and P <0.001, respectively). This generated an AUC of 0.79 (95% CI: 0.70-0.88, sensitivity 65%; specificity 82%) in predicting malignant disease.

CONCLUSION

Bile collected during biliary drainage contains miRNAs able to differentiate benign from malignant pancreaticobiliary diseases in patients with obstructive jaundice. These bile miRNAs have the potential to increase diagnostic accuracy.

Cholangiocarcinoma imaging: from diagnosis to response assessment

Cholangiocarcinoma (CCA), a highly aggressive primary liver cancer arising from the bile duct epithelium, represents a substantial proportion of hepatobiliary malignancies, posing formidable challenges in diagnosis and treatment. Notably, the global incidence of intrahepatic CCA has seen a rise, necessitating a critical examination of diagnostic and management strategies, especially due to presence of close imaging mimics such as hepatocellular carcinoma (HCC) and combined hepatocellular carcinoma-cholangiocarcinoma (cHCC-CCA). Hence, it is imperative to understand the role of various imaging modalities such as ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI), elucidating their strengths, and limitations in diagnostic precision and staging accuracy. Beyond conventional approaches, there is emerging significance of functional imaging tools including positron emission tomography (PET)-CT and diffusion-weighted (DW)-MRI, providing pivotal insights into diagnosis, therapeutic assessment, and prognostic evaluation. This comprehensive review explores the risk factors, classification, clinical features, and role of imaging in the holistic spectrum of diagnosis, staging, management, and restaging for CCA, hence serving as a valuable resource for radiologists evaluating CCA.

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.

Imaging mimickers of cholangiocarcinoma: a pictorial review

Cholangiocarcinoma (CCA) is the second most common primary hepatobiliary malignancy and presents as three separate morphological subtypes; namely mass-forming, periductal-infiltrating, and intraductal-growing patterns. Each of these subtypes have distinct imaging characteristics, as well as a variety of benign and malignant mimics, making accurate diagnosis of CCA on imaging challenging. Whilst histopathological examination is required to arrive at a definitive diagnosis, it is still important for radiologists to be cognizant of these entities and provide reasonable differential diagnoses, as these potentially have a large impact on patient management. This pictorial essay illustrates the three morphological subtypes of CCA, as well as some important mimics for each subtype, that are encountered in clinical practice.

Diagnostic Accuracy of Magnetic Resonance Cholangiopancreatography to Detect Benign and Malignant Biliary Strictures

Background:

Magnetic resonance cholangiopancreatography (MRCP) is a noninvasive method to detect pancreaticobiliary strictures. In this study, we aimed to evaluate the diagnostic performance of MRCP and detect sensitive and specific radiologic features in distinguishing malignant and benign pathologies.

Materials and Methods:

In this study, 50 patients with biliary obstruction and a confirmed diagnosis using histopathology were included. The pathologies were evaluated using MRCP which were categorized into malignant and benign strictures. The etiology of strictures was detected using histopathology and endoscopic retrograde cholangiopancreatography. The diagnostic performance of MRCP was calculated using SPSS software. P < 0.05 was considered statistically significant.

Results:

Of 50 patients, 23 patients (46%) had malignant strictures based on MRCP and histopathology. The sensitivity and specificity of MRCP to detect malignancy were 95.7% and 96.3%, respectively. The most sensitive MRCP features to detect malignancy were upstream biliary duct dilation, abrupt tapering, and the presence of a solid mass with sensitivity 100%, 95.7%, and 78.2%, respectively. The malignancy rate was significantly higher in the strictures with length >11.5 mm or wall thickness >2.75 mm (P < 0.05).

Conclusion:

MRCP is a sensitive method to differentiate malignant lesions from benign pathologies. A long and thick stricture with the presence of a solid mass, upstream biliary duct dilation, and abrupt tapering is highly suggestive of malignancy.

MRCP Combined With CT Promotes the Differentiation of Benign and Malignant Distal Bile Duct Strictures

Objective

To determine whether contrast-enhanced computed tomography (CT) can promote the identification of malignant and benign distal biliary strictures (DBSs) compared to the use of magnetic resonance cholangiopancreatography (MRCP) alone and to identify imaging findings of malignant DBSs.

Materials and Methods

A total of 168 consecutive patients with confirmed DBSs were reviewed. MRCP alone and MRCP combined with CT images were blindly analyzed by two radiologists (e.g., stricture pattern, margins), and malignant or benign DBSs were identified based on surgical findings, endoscopy findings, or follow-up. The diagnostic accuracy of the two reviewers using MRCP alone and MRCP combined with CT were evaluated. MRCP and CT features of malignant and benign DBSs were compared using multiple logistic regression analysis to identify independent malignant risk factors.

Results

MRCP combined with CT examination could improve the diagnostic accuracy, which increased from 70.2% to 81.5% in Doctor A and from 85.1% to 89.3% in Doctor B. The multiple logistic regression model revealed that stricture length [odds ratio (OR) 1.070, P=0.016], angle of the DBS (OR 1.061, P<0.001), double duct sign (OR 4.312, P=0.003) and low density in the arterial phase (OR 0.319, P=0.018) were associated with malignant DBS. A scoring model incorporating these four factors was established; at a threshold value of 1.75, and the sensitivity and specificity for the detection of malignant DBSs were 73.5 and 85.9%, respectively.

Conclusions

Compared to the use of MRCP alone, MRCP combined with contrast-enhanced CT can improve the accuracy of DBS diagnosis. The scoring model accurately predicts malignant DBSs and helps make treatment decisions.

Feasibility of magnetic resonance imaging-based radiomics features for preoperative prediction of extrahepatic cholangiocarcinoma stage

AIM

The aim of this study is to develop and test radiomics models based on magnetic resonance imaging (MRI) to preoperatively and respectively predict the T stage, perineural invasion, and microvascular invasion of extrahepatic cholangiocarcinoma (eCCA) through a non-invasive approach.

METHODS

This research included 101 eCCA patients (29-83 years; 45 females and 56 males) between August 2011 and December 2019. Radiomics features were retrospectively extracted from T1-weighted imaging, T2-weighted imaging, diffusion-weighted imaging, and apparent diffusion coefficient map using MaZda software. The region of interest was manually delineated in the largest section on four MRI images as ground truth while keeping 1-2 mm margin to tumor border, respectively. Pretreatment, dimension reduction method, and classifiers were used to establish radiomics signatures for assessing three pathological characteristics of eCCA. Finally, independent training and testing datasets were used to assess radiomics signature performance based on receiver operating characteristic curve analysis, accuracy, precision, sensitivity, and specificity.

RESULTS

This study extracted 1208 radiomics features from four MRI images of each patient. The best performing radiomics signatures for assessing the T stage, perineural invasion, and microvascular invasion were respectively produced by L1_normalization + linear discriminant analysis (LDA) + logistic regression, Box_Cox transformer + LDA + K-nearest neighbor, and L2_normalization + LDA + AdaBoost. The area under the curve values of the radiomics signatures for predicting the training and testing cohorts in each subgroup were respectively 1 and 0.962 (T stage), 1 and 1 (both perineural invasion and microvascular invasion).

CONCLUSION

These proposed radiomic models based on MR images had powerful performance and high potential in predicting T stage, perineural, and microvascular invasion of eCCA.

REPORTING GUIDELINES/RESEARCH DESIGN

Prognostic study.

Imaging of Ampullary and Periampullary Conditions

The ampulla of Vater is formed by the union of the pancreatic duct and the common bile duct and is also known as hepatopancreatic ampulla or hepatopancreatic duct. The ampulla is surrounded by a muscular valve known as the sphincter of Oddi, which controls the flow of bile and pancreatic juices into the duodenum in response to food. The ampulla is also an important embryological landmark as it marks the anatomical transition from foregut to the midgut. Because of this, it is a watershed zone where the blood supply changes from the celiac axis to the superior mesenteric artery. Radiologic evaluation of the ampulla and the periampullary region is challenging because it requires an understanding of the embryology, the normal appearance, and different anatomic variants. Also, a wide variety of pathologies can occur in this region. The purpose of this review is to present the normal anatomy of the ampulla and the periampullary region on different imaging modalities and to summarize the imaging features of the common variants, and benign and malignant ampullary and periampullary conditions. Understanding of the normal anatomical appearance and variants along with the knowledge of common pathologic conditions affecting the ampulla and periampullary conditions can help radiologists in making accurate diagnosis resulting in optimum patient care.

Italian Clinical Practice Guidelines on Cholangiocarcinoma - Part I: Classification, diagnosis and staging

Cholangiocarcinoma (CCA) is the second most common primary liver cancer, characterized by a poor prognosis and resistance to chemotherapeutics. The progressive increase in CCA incidence and mortality registered worldwide in the last two decades and the need to clarify various aspects of clinical management have prompted the Italian Association for the Study of the Liver (AISF) to commission the drafting of dedicated guidelines in collaboration with a group of Italian scientific societies. These guidelines have been formulated in accordance with the Italian National Institute of Health indications and developed by following the GRADE method and related advancements.

Non-neoplastic cholangiopathies: an algorithmic approach

Cholangiopathies are chronic diseases that affect the bile ducts, comprising a heterogeneous group of progressive and potentially fatal entities. The diagnosis of these diseases is a great challenge for radiologists because of the overlapping of their clinical, biochemical, and imaging findings. Nevertheless, identifying the precise etiology is crucial, given that the therapeutic options are distinct and influence the prognosis of the patient. The purpose of this review article is to discuss some of the non-neoplastic causes of cholangiopathies and to provide a useful diagnostic algorithm.

Challenging biliary strictures: pathophysiological features, differential diagnosis, diagnostic algorithms, and new clinically relevant biomarkers - part 1

It is frequently challenging to make the correct diagnosis in patients with biliary strictures. This is particularly important as errors may have disastrous consequences. Benign-appearing strictures treated with stents may later be revealed to be malignant and unnecessary surgery for benign strictures carries a high morbidity rate. In the first part of the review, the essential information that clinicians need to know about diseases responsible for biliary strictures is presented, with a focus on the most recent data. Then, the characteristics and pitfalls of the methods used to make the diagnosis are summarized. These include serum biomarkers, imaging studies, and endoscopic modalities. As tissue diagnosis is the only 100% specific tool, it is described in detail, including techniques for tissue acquisition and their yields, how to prepare samples, and what to expect from the pathologist. Tricks to increase diagnostic yields are described. Clues are then presented for the differential diagnosis between primary and secondary sclerosing cholangitis, IgG4-related sclerosing cholangitis, cholangiocarcinoma, pancreatic cancer, autoimmune pancreatitis, and less frequent diseases. Finally, algorithms that will help to achieve the correct diagnosis are proposed.

Preoperative magnetic resonance cholangiopancreatography before planned laparoscopic cholecystectomy: is it necessary?

Background:

The most feared complication of laparoscopic cholecystectomy (LC) is biliary tract injuries (BTI). We conducted a prospective study to evaluate the role of preoperative magnetic resonance cholangiopancreatography (MRCP) in describing the biliary tract anatomy and to investigate its potential benefit to prevent BTI.

Materials and Methods:

From January 2012 to December 2016, 402 patients who underwent LC with preoperative MRCP were prospectively included. Routine intraoperative cholangiography was not performed. Patients' characteristics, preoperative diagnosis, biliary anatomy, conversion to laparotomy, and the incidence of BTI were analyzed.

Results:

Preoperative MRCP was performed prospectively in 402 patients. LC was indicated for cholecystitis and pancreatitis, respectively, in 119 (29.6%) and 53 (13.2%) patients. One hundred and five (26%) patients had anatomical variations of biliary tract. Three BTI (0.75%) occurred with a major BTI (Strasberg E) and two bile leakage from the cystic stump (Strasberg A). For these 3 patients, biliary anatomy was modal on MRCP. No BTI occurred in patients presenting “dangerous” biliary anatomical variations.

Conclusion:

MRCP could be a valuable tool to study preoperatively the biliary anatomy and to recognize “dangerous” anatomical variations. Subsequent BTI might be avoided. Further randomized trials should be designed to assess its real value as a routine investigation before LC.

Serum cell-free DNA methylation of OPCML and HOXD9 as a biomarker that may aid in differential diagnosis between cholangiocarcinoma and other biliary diseases

BACKGROUND

Cholangiocarcinoma (CCA) is a fatal cancer of the bile duct epithelial cell lining. The misdiagnosis of CCA and other biliary diseases may occur due to the similarity of clinical manifestations and blood tests resulting in inappropriate or delayed treatment. Thus, an accurate and less-invasive method for differentiating CCA from other biliary diseases is inevitable.

METHODS

We quantified methylation of OPCML, HOXA9, and HOXD9 in serum cell-free DNA (cfDNA) of CCA patients and other biliary diseases using methylation-sensitive high-resolution melting (MS-HRM). Their potency as differential biomarkers between CCA and other biliary diseases was also evaluated by using receiver operating characteristic (ROC) curves.

RESULTS

The significant difference of methylation levels of OPCML and HOXD9 was observed in serum cfDNA of CCA compared to other biliary diseases. Assessment of serum cfDNA methylation of OPCML and HOXD9 as differential biomarkers of CCA and other biliary diseases showed the area under curve (AUC) of 0.850 (0.759-0.941) for OPCML which sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were 80.00%, 90.00%, 88.88%, 81.81%, and 85.00%, respectively. The AUC of HOXD9 was 0.789 (0.686-0.892) with sensitivity, specificity, PPV, NPV, and accuracy of 67.50%, 90.00%, 87.09%, 73.46%, and 78.75%, respectively. The combined marker between OPCML and HOXD9 showed sensitivity, specificity, PPV, and NPV of 62.50%, 100%, 100%, and 72.72%, respectively, which may be helpful to prevent a misdiagnosis between CCA and other biliary diseases.

CONCLUSIONS

Our findings suggest the application of serum cfDNA methylation of OPCML and HOXD9 for differential diagnosis of CCA and other biliary diseases due to its less invasiveness and clinically practical method which may benefit the patients by preventing the misdiagnosis of CCA and avoiding unnecessary surgical intervention.

Role of MRCP in Differentiation of Benign and Malignant Causes of Biliary Obstruction

BACKGROUND

Differentiation of the benign and malignant etiology of biliary obstruction is difficult. We studied the diagnostic accuracy of MRCP (Magnetic Resonance Cholangio-pancreatography) in differentiating between benign and malignant causes of biliary obstruction.

AIM

To evaluate the role of Magnetic Resonance Cholangio-Pancreatography in differentiating benign from malignant causes of biliary obstruction using surgical, ERCP or histopathological findings as gold standard.

MATERIALS AND METHODS

Seventy five patients with clinical and laboratory finding suggestive of biliary obstruction underwent MRI/MRCP. The final diagnosis was based on either surgical findings, histopathology of resected specimen or ERCP findings. Diagnostic effectivity of MRCP was calculated which included sensitivity, specificity and accuracy. Statistical analysis was done by using chi-square test and p value was calculated.

RESULTS

Out of 75 cases, there were 54 benign and 21 malignant cases. Mean age of patients with malignant obstruction was more than benign with slight male preponderance. The diagnostic accuracy of MRCP in differentiating benign from malignant biliary obstructive diseases in correlation with surgical, ERCP and histopathological outcome was 93.3%, sensitivity 85.7%, specificity 96.3%. It was found that irregular, asymmetric and long segment narrowing was more common in malignant stricture.

CONCLUSIONS

MRCP is the investigation of choice for suspected choledocholithiasis, choledochal cyst and primary sclerosing cholangitis. A benign stricture can be differentiated from a malignant one if it shows regular, symmetric and short segment narrowing. Irregular, asymmetric and long segment narrowing was more commonly found in malignant stricture.

Use of Imaging for GI Cancers

GI cancers are a heterogeneous group of neoplasms that differ in their biologic and physical behaviors depending on the organ of origin, location within the organ, and degree of differentiation. As a result, evaluation of these tumors is complex, requiring integration of information from a patient's clinical history, physical examination, laboratory data, and imaging. With advances in anatomic and functional imaging techniques, we now have tools for assessing patients with these tumors at diagnosis, staging, and treatment assessment. It is difficult for a single imaging modality to provide all the necessary information for a given GI tumor. However, well-chosen combinations of available imaging modalities based on the indications, strength, and limitations of the modalities will provide optimal evaluation of patients with these malignancies.

Radiological diagnosis in cholangiocarcinoma: Application of computed tomography, magnetic resonance imaging, and positron emission tomography

The purpose of radiological imaging in patients with suspected or known cholangiocarcinoma (CCA) is tumour detection, lesion characterization and assessment of resectability. Different imaging modalities are implemented complementary in the diagnostic work-up. Non-invasive imaging should be performed prior to invasive biliary procedures in order to avoid false positive results. For assessment of intraparenchymal tumour extension and evaluation of biliary and vascular invasion, MRI including MRCP and CT are the primarily used imaging modalities. The role of PET remains controversial with few studies showing benefit with the detection of unexpected metastatic spread, the differentiation between benign and malignant biliary strictures, and for discriminating post therapeutic changes and recurrent CCA.