MRI combined with MR cholangiopancreatography versus helical CT in the evaluation of patients with suspected periampullary tumors: a prospective comparative study

Differentiation of malignant from benign ampullary strictures: A prediction nomogram based on MR imaging and clinical findings

PURPOSE

To construct a predictive nomogram based on contrast-enhanced magnetic resonance imaging (MRI) and clinical findings for differentiating malignant from benign ampullary strictures.

METHOD

In this retrospective study, 76 patients with ampullary strictures (51 benign and 25 malignant) who underwent contrast-enhanced MRI were enrolled. Imaging findings were evaluated independently by two abdominal radiologists who reached consensus. Clinical findings were also collected. Significant findings for malignant ampullary strictures were assessed by univariable and multivariable logistic regression analyses. Based on the results of multivariable analysis, a nomogram to differentiate malignant from benign ampullary strictures was developed and internally validated.

RESULTS

In multivariable analysis, presence of an ampullary mass (odds ratio [OR]: 8.42, p = 0.047), bulging ampulla (OR: 8.32, p = 0.033), diffusion restriction of the ampulla (OR: 42.76, p = 0.004) on MRI, and jaundice (OR: 12.41, p = 0.019) were significant predictors of malignant ampullary strictures. A predictive nomogram was constructed using these findings. Among them, diffusion restriction of the ampulla showed the highest OR and predictor score on the nomogram. The calibration plots for internal validation achieved strong agreement between the predicted probabilities and the actual rates of malignant ampullary strictures.

CONCLUSION

A combination of significant contrast-enhanced MRI and clinical findings of ampullary mass, bulging ampulla, diffusion restriction of the ampulla, and jaundice may be useful in the prediction of malignant ampullary stricture.

Diagnostic value of endoscopic ultrasonography in periampullary duodenal tumours

Introduction

The objective of this study was to investigate the diagnostic value of endoscopic ultrasonography (EUS) for tumours around the duodenal ampullary.

Patients and Methods

A retrospective analysis was performed on cases diagnosed and treated in our hospital from October 2016 to August 2021 due to the lesions around the duodenal ampulla. All patients received EUS, abdominal enhanced computed tomography (CT) and magnetic resonance imaging combined with magnetic resonance cholangiopancreatography (MRI-MRCP). Pathological diagnosis was used to verify the accuracy of the imaging findings. The detection rates of periampullary tumours by EUS, abdominal enhanced CT and MRI-MRCP were determined and compared.

Results

A total of 86 patients were included in this study. According to the pathological diagnosis, the detection rate of EUS was 87% (36/41) for periampullary tumour lesions with a tumour diameter <1 cm, which was significantly higher than that of MRI-MRCP (59%, 24/41) (P = 0.003) and CT (44%, 18/41) (P < 0.001). For periampullary tumour lesions with a tumour diameter ≥1 cm, the detection rate of MRI-MRCP was 93% (42/45), which was significantly higher than that of EUS (78%, 35/45) (P = 0.036) and CT (76%, 34/45) (P = 0.02).

Conclusions

EUS can accurately detect tumour lesions around the ampullary part of the duodenum with minimal gas interference. For periampullary tumour lesions <1 cm, EUS has better diagnostic accuracy than abdominal-enhanced CT and MRI-MRCP. In addition, a biopsy of the lesion can be performed at the same time during the EUS examination. Therefore, EUS has an important clinical significance and value in the diagnosis of duodenal periampullary tumours.

Evaluation of Imaging Findings of Pancreatobiliary and Intestinal Type Periampullary Carcinomas with 3.0T MRI

RATIONALE AND OBJECTIVES

The aim of this study was to differentiate pancreatobiliary and intestinal type periampullary carcinomas using dynamic contrast MRI and MRCP (Magnetic Resonance Cholangiopancreatography) with diffusion-weighted imaging (DWI) MATERIALS AND METHODS: MRI and MRCP images of 70 patients with pathologically proven periampullary adenocarcinoma were included. MRCP image features, extra-ampullary features, enhancement patterns, and apparent diffusion coefficient (ADC) values derived from b-values of 1000 s/mm² were evaluated by two radiologists independently. The interclass correlation coefficient (ICC) or Cohen's kappa statistic was used to evaluate the interobserver agreement.

RESULTS

51 patients were diagnosed with pancreatobiliary type carcinomas, and 19 with intestinal type. In the pancreatobiliary subtype, the distal wall of the common bile duct was usually irregular (p = 0.047). Although the progressive enhancement pattern was evident in the pancreatobiliary type, an oval filling defect in the distal common bile duct was found to be more common in the intestinal type (p<0.001). The pancreatic duct cut-off sign (p<0.001), gastroduodenal artery involvement (p <0,001), and lymphadenopathy (p<0.05) were mostly observed in pancreatobiliary carcinomas. The ADCmin, ADCmean, and ADCmax values of the pancreatobiliary type carcinomas were all lower compared to the intestinal type carcinomas (p <0.05).

CONCLUSION

The oval filling defect seen in MRI and MRCP examinations suggests intestinal type, whereas the progressive contrasting pattern of the masses with irregular narrowing in the distal margin of the common bile duct, the pancreatic duct cut-off sign, gastroduodenal artery involvement, lymphadenopathy, and low ADC values indicate pancreatobiliary type carcinomas.

Differentiating between benign and malignant ampullary strictures: a prediction model using a nomogram based on CT imaging and clinical findings

OBJECTIVES

To construct a predictive nomogram for differentiating malignant from benign ampullary strictures using contrast-enhanced computed tomography (CT) findings combined with clinical findings.

METHODS

In this retrospective study, 152 patients with ampullary stricture (98 benign and 54 malignant) who underwent contrast-enhanced CT were included. Various imaging findings of the ampulla, bile duct, main pancreatic duct, and periampullary area were evaluated and clinical findings including the presence of jaundice, carbohydrate antigen 19-9 level, and history of cholecystectomy were collected. Among them, statistically significant findings were identified using univariable and multivariable logistic regression analyses. A nomogram was constructed to differentiate benign and malignant ampullary strictures and was internally validated.

RESULTS

Multivariable analysis revealed that jaundice (odds ratio [OR]: 17.33, p < 0.001), presence of an ampullary mass (OR: 24.40, p < 0.001), non-similar enhancement of the ampulla to the duodenum (OR: 31.96, p = 0.003), and proportional dilatation of the bile duct (OR: 7.98, p = 0.001) were independent significant factors for predicting the malignant ampullary stricture, and were used to construct a nomogram. Among them, non-similar enhancement of the ampulla to the duodenum showed the highest OR and predictor point on the nomogram. The calibration plots showed excellent agreement between the predicted probabilities and the actual rates of malignant ampullary strictures, on internal validation.

CONCLUSIONS

Combination of clinical and imaging findings could aid in predicting malignant ampullary strictures using significant findings of jaundice, presence of ampullary mass, non-similar enhancement of the ampulla to the duodenum, and proportional dilatation of the bile duct.

KEY POINTS

• The presence of jaundice, ampullary mass, non-similar enhancement of the ampulla, and proportional bile duct dilatation were significant findings for predicting malignant ampullary strictures. • Non-similar enhancement of the ampulla to the duodenum was a significant feature with the highest odds ratio for differentiating benign and malignant ampullary strictures. • The nomogram constructed using contrast-enhanced computed tomography imaging and clinical findings could aid in predicting malignant ampullary strictures.

Korean clinical practice guideline for pancreatic cancer 2021: A summary of evidence-based, multi-disciplinary diagnostic and therapeutic approaches

Pancreatic cancer is the eighth most common cancer and the fifth most common cause of cancer-related death in Korea. To enable standardization of management and facilitate improvements in outcome, a total of 53 multi-disciplinary experts in gastroenterology, surgery, medical oncology, radiation oncology, radiology, nuclear medicine, and pathology in Korea developed new recommendations that integrate the most up-to-date, evidence-based research findings and expert opinions. Recommendations were made on imaging diagnosis, endoscopic management, surgery, radiotherapy, palliative chemotherapy, and specific management procedures, including neoadjuvant treatment or adjuvant treatment for patients with resectable, borderline resectable, and locally advanced unresectable pancreatic cancer. This is the English version of the Korean clinical practice guideline for pancreatic cancer 2021. This guideline includes 20 clinical questions and 32 statements. This guideline represents the most standard guideline for the diagnosis and treatment of patients with pancreatic ductal adenocarcinoma in adults at this time in Korea. The authors believe that this guideline will provide useful and informative advice.

Indian College of Radiology and Imaging Evidence-Based Guidelines for Percutaneous Image-Guided Biliary Procedures

Percutaneous biliary interventions are among the commonly performed nonvascular radiological interventions. Most common of these interventions is the percutaneous transhepatic biliary drainage for malignant biliary obstruction. Other biliary procedures performed include percutaneous cholecystostomy, biliary stenting, drainage for bile leaks, and various procedures like balloon dilatation, stenting, and large-bore catheter drainage for bilioenteric or post-transplant anastomotic strictures. Although these procedures are being performed for ages, no standard guidelines have been formulated. This article attempts at preparing guidelines for performing various percutaneous image-guided biliary procedures along with discussion on the published evidence in this field.

Combining endoscopic ultrasound and tumor markers improves the diagnostic yield on the etiology of common bile duct dilation secondary to periampullary pathologies

Background

Unexplained common bile duct (CBD) dilatation may be caused by many etiologies, such as periampullary tumors, a pancreatic neoplasm, choledocholithiasis or an inflammatory stenosis. The aim of this study is to evaluate the diagnostic yield of endoscopic ultrasonography (EUS) in patients with unexplained CBD dilatation, in combination with tumor markers, liver chemistry, symptoms, surgical history and whether there is dilatation of the pancreatic duct (PD).

Methods

From January 2016 to July 2017, 115 patients were referred for EUS in our center for CBD dilatation of an unknown etiology. A treatment plan is made based on the EUS result combined with the other clinical information. The final diagnosis is determined by surgical histology or follow-up of at least 3 months.

Results

The sensitivity, specificity and accuracy of EUS for patients with choledocholithiasis were 100.0% (10/10), 100.0% (105/105) and 100.0% (115/115), respectively. The sensitivity, specificity and accuracy of EUS for patients with periampullary tumor were 86.5% (32/37), 89.7% (70/78) and 88.7% (102/115), respectively. The sensitivity, specificity and accuracy of EUS for patients with inflammatory stenosis were 88.2% (60/68), 89.4% (42/47) and 88.7% (102/115), respectively. The overall accuracy of EUS for diagnosing an undetermined etiology for CBD dilatation was 88.7% (102/115) and was higher than the accuracy of ultrasound (US) (64.1%), computed tomography (CT) (66.2%), magnetic resonance imaging (MRI) (67.0%) or PET-CT (66.0%). The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of EUS combined with tumor markers for patients with malignant dilatation of CBD were 91.9% (34/37), 97.4% (76/78), 94.4% (34/36), 96.2% (76/79) and 95.7% (110/115), respectively. PD dilation (P=0.026) and weight loss (P=0.035) had significant predictive values of malignancy.

Conclusions

EUS is an effective diagnostic tool for determining the etiology of a CBD dilatation, and offers meaningful information for guiding a treatment plan. EUS used in conjunction with tumor markers has high yield in differentiating benign and malignant CBD dilatation. More attention should be paid to patients with PD dilation or weight loss to prevent misdiagnosis of malignant CBD dilation.

Combination of CEUS and MRI for the diagnosis of periampullary space-occupying lesions: a retrospective analysis

Background

The value of magnetic resonance imaging (MRI), contrast-enhanced ultrasound (CEUS), and the combination of CEUS and MRI (CCWM) for the diagnosis of periampullary space-occupying lesions (PSOL) was investigated.

Methods

A total of 102 patients diagnosed with PSOLs by surgery or biopsy were recruited retrospectively. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of MRI, CEUS, and CCWM were analyzed.

Results

MRI, CEUS, and CCWM allowed for the accurate detection of 91.17, 92.15, and 99.01% of PSOLs, respectively. The specificity, PPV, and accuracy of CCWM were significantly different from MRI and CEUS (p < 0.05). However, there the sensitivity and NPV were not significantly different among the three diagnostic technologies. In addition, the specificity, PPV, and accuracy were not significantly different between MRI and CEUS (all p > 0.05).

Conclusions

CCWM is valuable for differentiating benign and malignant PSOL, which provides important guiding significances for the clinic.

Ultrasound diagnosis of pancreatic solid tumors

INTRODUCTION

Advances and widespread use of various diagnostic imaging modalities have dramatically improved our ability to visualize and diagnose pancreatic diseases. In particular, ultrasonography in pancreatic diseases plays an important role from screening to diagnosis as a simple and safe examination method.

METHODS

The basic scanning method of transabdominal pancreatic ultrasonography, characterization, and differential diagnosis by ultrasonography including contrast-enhanced ultrasonography (CEUS) for solid pancreatic tumors are reviewed with reference to various papers.

RESULTS

In recent years, the ability to visualize and diagnose pancreatic mass lesions has been dramatically improved with advances in ultrasound equipment. In particular, CEUS using an ultrasound contrast agent has made it possible to evaluate hemodynamics in organs or lesions as well as in the flow signal of arterial blood vessels, and it has played an important role not only in diagnosis of the presence of a lesion but also in the qualitative diagnosis. The enhancement behavior and pattern with CEUS of pancreatic solid tumors is shown in text and Fig. 9. Moreover, the flow chart for diagnosing pancreatic solid tumors with CEUS classifying the enhancement behavior and pattern for pancreatic solid tumors on CEUS is shown (Fig. 10). In meta-analyses, the pooled sensitivity in the differential diagnosis of pancreatic adenocarcinomas and other pancreatic focal masses with CEUS was 86-90%, and the pooled specificity was 75-88%.

CONCLUSION

CEUS is a minimally invasive and useful diagnostic method that can be used to make a simple and quick qualitative diagnosis of pancreatic diseases. CEUS provides a lot of information important for diagnosis, and has led to changes in the conventional diagnostic systems in pancreatic diseases.

The clinical value of secretin-enhanced MRCP in the functional and morphological assessment of pancreatic diseases

Secretin-enhanced magnetic resonance cholangiopancreatography (S-MRCP) provides a non-invasive way, with which, to evaluate pancreatic duct (PD) anatomy and exocrine pancreatic function. S-MRCP can be added to the routine pancreas MR examination in equivocal cases. Moreover, it can detect subtle PD involvement, allowing diagnosis of early, rather than end-stage, pancreatic diseases. Although S-MRCP is a valuable non-invasive diagnostic method, it is only performed in a few centres due to relative high cost. Furthermore, less familiarity with its indications, the examination technique, and image interpretation also contribute to its limited use. Thus, the purpose of this article is to explain secretin's mechanism of action, the examination technique, the clinically relevant indications, the advantages, and limitations. Finally, we will focus on image analysis and its role in achieving an early and accurate diagnosis of specific pancreatic and PD diseases.

Preoperative Evaluation of Malignant Perihilar Biliary Obstruction: Negative-Contrast CT Cholangiopancreatography and CT Angiography Versus MRCP and MR Angiography

OBJECTIVE

The purpose of this study was to compare negative-contrast CT cholangiopancreatography (CTCP) and CT angiography (CTA) with MRCP and MR angiography (MRA) for the preoperative evaluation of malignant perihilar biliary obstruction.

MATERIALS AND METHODS

Twenty-one patients with pathologically proven malignant perihilar biliary obstructions who had undergone both CT and MRI examinations were reviewed retrospectively. Two reviewers independently analyzed the two image sets-the negative-contrast CTCP and CTA images (i.e., CT set) and the MRCP and MRA images (i.e., MRI set)-in preoperatively evaluating the classification of malignant perihilar biliary obstruction, hepatic artery and portal vein invasion, nodal metastasis, and organ spread. The results were compared with surgical and pathologic records.

RESULTS

For the classification of malignant perihilar biliary obstruction on the two image sets, the accuracy was not statistically significant (p = 1.000 for reviewer 1 and p = 0.500 for reviewer 2). For the evaluation of portal vein invasion, nodal metastasis, and organ spread, the accuracies were also not statistically significantly different (p = 0.335, 0.339, and 0.781 for reviewer 1; and p = 0.403, 0.495, and 0.325 for reviewer 2, respectively). In the assessment of hepatic artery status, the accuracy was statistically significant (p = 0.046 for reviewer 1 and p = 0.036 for reviewer 2).

CONCLUSION

Compared with the MRI set, the CT set provides equivalent performance in assessing the classification of malignant perihilar biliary obstruction, portal vein involvement, nodal metastasis, and organ spread, but has higher accuracy in assessing arterial invasion.

Differentiation of pancreatobiliary-type from intestinal-type periampullary carcinomas using 3.0T MRI

PURPOSE

To differentiate pancreatobiliary-type from intestinal-type periampullary carcinomas using combined magnetic resonance cholangiopancreatography (MRCP), contrast-enhanced MRI, and diffusion-weighted imaging (DWI).

MATERIALS AND METHODS

MRI (3.0T) results of 41 patients with pathologically confirmed periampullary carcinoma were retrospectively assessed. Two radiologists, blinded to histologic type of each tumor, evaluated image findings independently. MRCP image features, enhancement pattern, and apparent diffusion coefficient (ADC) values were analyzed. Independent-sample t-test, chi-square, or Fisher's exact test were used to determine differential image findings between the pancreatobiliary-type and the intestinal-type group. Cohen's κ statistic or interclass correlation coefficient (ICC) were used to evaluate interobserver agreement between two observers. Univariate and multiple logistic regression analysis were performed to identify MRI features with predictive values.

RESULTS

On the basis of hematoxylin-eosin staining, 27 patients were classified as having pancreatobiliary-type carcinomas, and 14 patients the intestinal type. The pancreatobiliary-type carcinomas more commonly showed progressive enhancement than the intestinal type (P = 0.003). The minimum ADC (ADCmin ) value of the pancreatobiliary-type group ([0.95 ± 0.21] × 10(-3) mm(2) /s) was significantly lower than the intestinal-type group ([1.10 ± 0.25] × 10(-3) mm(2) /s) (P = 0.047). For interobserver agreement, the κ values and ICCs for all parameters exceeded 0.8, indicating almost perfect agreement. At multiple logistic regression analysis, the enhancement pattern was the only significant independent predictor (P = 0.011, odds ratio [OR] = 0.105). When the enhancement pattern and ADCmin were used in combination, we could identify 70.4% of pancreatobiliary-type and 78.6% of intestinal-type carcinomas.

CONCLUSION

Progressive enhancement and low ADCmin values suggest a pancreatobiliary-type periampullary carcinoma.

Diagnostic Accuracy of MRCP as Compared to Ultrasound/CT in Patients with Obstructive Jaundice

BACKGROUND

The expanding spectrum of therapeutic options for patients with surgical jaundice makes it necessary for the radiologist to precisely assess the etiology, location, level and extent of disease.

AIM

To compare the diagnostic accuracy of Magnetic Resonance Cholangiopancreatography (MRCP) with Ultrasound and Computed Tomography (CT) in evaluation of patients with obstructive jaundice taking direct cholangiographies (ERCP and PTC), hystologic tests and anatomo-pathological findings after surgical intervention as gold standard.

SETTINGS AND DESIGN

This prospective study included 50 patients who were referred to the radiology department with clinical features of biliary obstructive disease.

MATERIALS AND METHODS

Initial ultrasonography (USG) evaluation was followed by Computed tomography (CT) and Magnetic Resonance Cholangiopancreatography (MRCP);however in cases of benign pathologies where USG findings were unequivocal Computed tomography (CT )was not done to avoid unnecessary radiation exposure. The results were read by radiologists blinded to other imaging findings. The characteristic Endoscopic Retrograde Cholangiopancreatography (ERCP) features/ histopathological diagnosis / surgical findings (as applicable) were considered as final.

RESULTS

Diagnostic accuracy of MRCP (98%) in the diagnosis of benign and malignant diseases was relatively high (98% and 98%) as compared to CT (82.86% and 91.43% in benign and malignant respectively) and USG (88% and 88%). In the diagnosis of benign diseases MRCP was 100% sensitive compared to ultrasound (80.77%), which was more sensitive than CT scan (54.55%).In the diagnosis of malignant diseases, MRCP was more sensitive (95.83%) as compared to CT scan (91.67%), which was more sensitive than ultrasonography (79.17%).

CONCLUSION

Ultrasound as a screening modality is useful to confirm or exclude biliary dilatation and to choose patients for MRCP examination. MRCP is an important non invasive imaging investigation in the pre operative evaluation of patients with obstructive jaundice.

Magnetic resonance evaluations of biliary malignancy and condition at high-risk for biliary malignancy: Current status

Tumors of the biliary tree are relatively rare; but their incidence is rising worldwide. There are several known risk factors for bile duct cancers, and these are seem to be associated with chronic inflammation of the biliary epithelium. Herein, 2 risk factors have been discussed, primary sclerosing cholangitis and reflux of pancreatic juice into the bile duct, as seen in such as an abnormal union of the pancreatic-biliary junction because magnetic resonance imaging (MRI) is used widely and effectively in the diagnosis of these diseases. When biliary disease is suspected, MRI can often help differentiate between benignity and malignancy, stage tumors, select surgical candidates and guide surgical planning. MRI has many advantages over other modalities. Therefore, MRI is a reliable noninvasive imaging tool for diagnosis and pre-surgical evaluation of bile duct tumors. Nowadays remarkable technical advances in magnetic resonance technology have expanded the clinical applications of MRI in case of biliary diseases. In this article, it is also discussed how recent developments in MRI contributes to the diagnosis of the bile duct cancer and the evaluation of patients with risk factors affecting bile duct cancer.

Added value of diffusion-weighted MR imaging in the diagnosis of ampullary carcinoma

PURPOSE

To evaluate the added value of diffusion-weighted magnetic resonance (MR) imaging in diagnostic performance of conventional MR imaging for diagnosis of ampullary carcinoma.

MATERIALS AND METHODS

This retrospective study was institutional review board approved, and informed consent was waived. Twenty-three patients with malignant ampullary obstruction and 39 patients with benign ampullary obstruction were included. Qualitative (signal intensity and enhancement pattern) and quantitative (apparent diffusion coefficient [ADC]) analyses were conducted for visible or expected locations of duodenal papillae. Two observers independently reviewed conventional MR images and subsequently reviewed combined conventional and diffusion-weighted MR images. A five-point scale for likelihood of ampullary carcinoma was used. Fisher exact test and Mann-Whitney U test were used for comparing groups, and diagnostic performance (receiver operating characteristic [ROC] curve analysis), accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were evaluated.

RESULTS

Visible or expected duodenal papillae in benign group showed isointensity (27-38 of 39, 69%-97%) and similar enhancement pattern (27 of 39, 69%) to that of normal duodenal wall more frequently than in malignant group (seven to 18 of 23 [30%-78%] and three of 23 [13%], respectively) on conventional MR images (P < .05). On diffusion-weighted images, 21 of 23 (91%) ampullary carcinomas showed hyperintensity, whereas all benign cases showed isointensity compared with normal duodenal wall (P < .001). Mean ADC of ampullary carcinomas (1.23 × 10(-3) mm(2)/sec) was significantly lower than that of benign group (1.69 × 10(-3) mm(2)/sec) (P < .001). Diagnostic performance (area under ROC curve [Az]) of both observers improved significantly after additional review of diffusion-weighted images; Az improved from 0.923 to 0.992 (P = .029) for observer 1 and from 0.910 to 0.992 (P = .025) for observer 2. In addition, diagnostic accuracy, sensitivity, specificity, PPV, and NPV of combined conventional and diffusion-weighted MR images were higher than those of conventional MR images alone.

CONCLUSION

Addition of diffusion-weighted imaging to conventional MR imaging improves detection of ampullary carcinoma when compared with conventional MR imaging alone.

Diffusion-weighted MR imaging for the differentiation of malignant from benign strictures in the periampullary region

OBJECTIVES

To investigate the value of DWI for differentiating malignant from benign strictures in the periampullary region.

METHODS

We retrospectively analysed data from 78 patients who had undergone magnetic resonance cholangiopanreatography (MRCP) and diffusion-weighted imaging (DWI), in whom biliary strictures in the periampullary region were suspected. Twenty-two malignant and 56 benign lesions were included. One radiologist compared the signal intensity of malignant and benign periampullary lesions on DWI using b = 500 and 800 s/mm(2). The signal intensity of bile was also compared, and an optimal b value was determined for periampullary lesions. Two other radiologists reviewed MRCP alone and combined DWI and MRCP for the possibility of malignant periampullary lesions. Diagnostic accuracy was calculated for each reviewer by receiver operating characteristic (ROC) curve analysis.

RESULTS

Malignant periampullary lesions more frequently appeared hyperintense than benign lesions on DWI using the two b values (P < 0.001). Bile more frequently appeared hyperintense on DWI using b = 500 s/mm(2) (87.2 %) than b = 800 s/mm(2) (24.4 %). Therefore, b = 800 s/mm(2) was determined as the preferred sequence. Diagnostic accuracy for malignant periampullary lesions improved for both reviewers after adding DWI; from 0.714 to 0.924 (P = 0.006, for reviewer 1) and from 0.714 to 0.919 (P = 0.007, reviewer 2).

CONCLUSIONS

Combined DWI with MRCP can improve the diagnostic accuracy for differentiating malignant from benign strictures in the periampullary region.

KEY POINTS

• Diffusion-weighted magnetic resonance imaging provides yet more information about hepatobiliary structures. • Diffusion-weighted imaging (DWI) has now been applied to the biliary tree. • Most periampullary carcinomas appear hyperintense on high b value DWI. • DWI can help differentiate between malignant and benign periampullary lesions.

Ductal adenocarcinoma of the pancreatic head: A focus on current diagnostic and surgical concepts

Complete surgical resection still remains the only possibility of curing pancreatic cancer, however, only 10% of patients undergo curative surgery. Pancreatic resection currently remains the only method of curing patients, and has a 5-year overall survival rate between 7%-34% compared to a median survival of 3-11 mo for unresected cancer. Pancreatic surgery is a technically demanding procedure requiring highly standardized surgical techniques. Nevertheless, even in experienced hands, perioperative morbidity rates (delayed gastric emptying, pancreatic fistula etc.) are as high as 50%. Different strategies to reduce postoperative morbidity, such as different techniques of gastroenteric reconstruction (pancreatico-jejunostomy vs pancreatico-gastrostomy), intraoperative placement of a pancreatic main duct stent or temporary sealing of the main pancreatic duct with fibrin glue have not led to a significant improvement in clinical outcome. The perioperative application of somatostatin or its analogues may decrease the incidence of pancreatic fistulas in cases with soft pancreatic tissue and a small main pancreatic duct (< 3 mm). The positive effects of external pancreatic main duct drainage and antecolic gastrointestinal reconstruction have been observed to decrease the rate of pancreatic fistulas and delayed gastric emptying, respectively. Currently, the concept of extended radical lymphadenectomy has been found to be associated with higher perioperative morbidity, but without any positive impact on overall survival. However, there is growing evidence that portal vein resections can be performed with acceptable low perioperative morbidity and mortality but does not achieve a cure.

Bilirubin levels predict malignancy in patients with obstructive jaundice

BACKGROUND

Differentiating between benign and malignant causes of obstructive jaundice can be challenging, even with the advanced imaging and endoscopic techniques currently available. In patients with obstructive jaundice, the predictive accuracy of bilirubin levels at presentation was examined in order to determine whether such data could be used to differentiate between malignant and benign disease.

METHODS

A total of 1,026 patients with obstructive jaundice were identified. Patients were divided into benign and malignant groups. The benign patients were subgrouped into those with choledocholithiasis and those with inflammatory strictures of the biliary tree. Bilirubin levels at presentation and other demographic data were obtained from case records.

RESULTS

Area under the curve (AUC) values for bilirubin as a predictor of malignancy were highly significant for all benign presentations and for those with benign biliary strictures (AUC: 0.8 for both groups; P < 0.001). A bilirubin level > 100 µmol/l was determined to provide the optimum sensitivity and specificity for malignancy in all patients and in those without choledocholithiasis (71.9% and 86.9%, 71.9% and 88.0%, respectively). The application of a bilirubin level > 250 µmol/l achieved specificities of 97.1% and 98.0% in each subgroup of patients, respectively.

CONCLUSIONS

In patients with obstructive jaundice, bilirubin levels in isolation represent an important tool for discriminating between benign and malignant underlying causes.

Advances in diagnosis, treatment and palliation of pancreatic carcinoma: 1990-2010

Several advances in genetics, diagnosis and palliation of pancreatic cancer (PC) have occurred in the last decades. A multidisciplinary approach to this disease is therefore recommended. PC is relatively common as it is the fourth leading cause of cancer related mortality. Most patients present with obstructive jaundice, epigastric or back pain, weight loss and anorexia. Despite improvements in diagnostic modalities, the majority of cases are still detected in advanced stages. The only curative treatment for PC remains surgical resection. No more than 20% of patients are candidates for surgery at the time of diagnosis and survival remains quite poor as adjuvant therapies are not very effective. A small percentage of patients with borderline non-resectable PC might benefit from neo-adjuvant chemoradiation therapy enabling them to undergo resection; however, randomized controlled studies are needed to prove the benefits of this strategy. Patients with unresectable PC benefit from palliative interventions such as biliary decompression and celiac plexus block. Further clinical trials to evaluate new chemo and radiation protocols as well as identification of genetic markers for PC are needed to improve the overall survival of patients affected by PC, as the current overall 5-year survival rate of patients affected by PC is still less than 5%. The aim of this article is to review the most recent high quality literature on this topic.

Differentiation of benign and malignant ampullary obstructions on MR imaging

OBJECTIVE

To define diagnostic criteria for differentiating malignant ampullary carcinoma from benign ampullary obstruction on MR imaging.

MATERIALS AND METHODS

Nineteen patients with ampullary carcinoma and 22 patients with benign ampullary obstruction were enrolled. At the first session, two radiologists independently evaluated specific imaging findings, and then reached consensus decisions. At the second session, another two radiologists, who were informed about useful differentiation criteria based on the results from the first session, reviewed images and determined the causes of ampullary obstruction. Sensitivity and specificity were calculated for each interpretation session, and the Cohen κ statistic was used to evaluate interobserver agreement.

RESULTS

Findings of the presence of an ampullary mass (P<0.001), papillary bulging (P<0.001), irregular (P=0.021) and asymmetric (P<0.001) common bile duct (CBD) narrowing, and proportional biliary dilatation (P<0.001) were more commonly seen in patients with an ampullary carcinoma. The sensitivity and specificity of the first session were 84.2% and 86.4% after consensus. The sensitivity increased to 100% for both the readers at the second session, while the specificity decreased to 63.6% and 59.1%, respectively.

CONCLUSIONS

Identification of an ampullary mass, papillary bulging, irregular and asymmetric narrowing of the CBD, or proportional biliary dilatation may improve the diagnosis of ampullary carcinoma in patients with ampullary obstruction.

Comparison between multislice CT and MR imaging in the diagnostic evaluation of patients with pancreatic masses

PURPOSE

This study compared the results of multislice computed tomography (MSCT) and high-field magnetic resonance imaging (MRI) in the diagnostic evaluation of pancreatic masses.

MATERIALS AND METHODS

Forty patients with clinical and ultrasonographic evidence of pancreatic masses underwent MSCT and MRI. The majority of patients (31/40, 78%) had proven malignant pancreatic tumours (24 ductal adenocarcinoma, six mucinous cystadenocarcinoma, one intraductal papillary mucinous carcinoma), whereas the remaining patients (9/40, 22%) were found to have benign lesions (eight chronic pancreatitis, one serous cystadenoma). Results of the imaging studies were compared with biopsy (n=33) and/or histology (n=7) findings to calculate sensitivity, specificity, accuracy and positive (PPV) and negative (NPV) predictive value for correct identification of tumours and evaluation of resectability of malignancies.

RESULTS

Both for tumour identification and resectability, MSCT and MRI had comparable diagnostic accuracy, with no statistically significant differences between them. Tumour identification CT/MRI: accuracy 98/98%, sensitivity 100/100%, specificity 88/88%, PPV 97/97%, NPV 100/100%; tumour resectability CT/MRI: accuracy 94/90%, sensitivity 92/88%, specificity 100/100%, PPV 100/100%, NPV 78/70%.

CONCLUSIONS

MRI represents a valid diagnostic alternative to CT in the evaluation of patients with pancreatic masses, both for correct identification and characterisation of primary lesions and to establish resectability in the case of malignancies. New high-field MRI equipment allows optimal imaging quality with good contrast resolution in evaluating the upper abdomen.

Palliation of malignant obstructive jaundice

Peri-ampullary and hepatic malignancies will frequently present with obstructive jaundice. For unresectable tumors, effective and lasting decompression of the biliary tree is essential to improve quality of life and survival. An overview of present treatment modalities for palliation of obstructive jaundice is provided, including a systematic review of the English literature regarding the optimum choice of palliation.

The integration of chemoradiation in the care of patient with localized pancreatic cancer

The use of chemoradiation for patients with localized pancreatic cancer is controversial. Although some randomized trials have indicated that chemoradiation improves the median survival of patients with locally advanced as well as resected pancreatic cancer, other more recent trials have called into question the role of chemoradiation and have supported the use of chemotherapy. In the adjuvant setting, the high local tumor recurrence/persistence rate in all trials probably reflects the inclusion of patients with incompletely resected tumors, whose prognosis is similar to the prognosis of patients with locally advanced who do not undergo resection, making these trials difficult to interpret. More precise clinical staging and selection of patients appropriate for surgical resection is an important goal. The keys to the successful integration of radiotherapy in the care of patients with localized pancreatic cancer are selection, sequencing and smaller treatment volumes. A strategy of initial chemotherapy followed by consolidation with a well-tolerated chemoradiation regimen both in the adjuvant and locally advanced settings maximizes benefits of both treatment options, which are in fact complementary. Herein, we discuss the rationale for this approach as well as the ongoing investigation of novel radiation approaches designed to enhance outcome through the molecular and physical targeting of disease as well as the investigation of neoadjuvant chemoradiation in radiographically resectable and borderline resectable pancreatic cancer.

Preoperative evaluation of bile duct cancer: MRI combined with MR cholangiopancreatography versus MDCT with direct cholangiography

OBJECTIVE

The purpose of this study was to compare the performance of MRI combined with MR cholangiopancreatography (MRCP) with that of MDCT combined with direct cholangiography in the evaluation of the tumor extent and resectability of bile duct cancer with surgical and pathologic findings as the reference standard.

MATERIALS AND METHODS

From January 2003 to March 2006, 27 patients (18 men, nine women; mean age, 60.8 years; range, 43-80 years) with surgically proven hilar cholangiocarcinoma or common bile duct (CBD) cancer who had undergone preoperative 2D and 3D MRCP with gadolinium-enhanced MRI and triple-phase MDCT with direct cholangiography (ERCP or percutaneous transhepatic cholangiography) were included in this retrospective study. Two experienced radiologists independently reviewed the two image sets. These readers evaluated the longitudinal extent of the tumor for involvement of the secondary confluence of both intrahepatic ducts and the intrapancreatic CBD, vascular involvement of the tumor, lymph node metastasis, and tumor resectability. The radiologists' performance was evaluated by calculation of sensitivity, specificity, and overall accuracy. Correlation was made with the resected specimens or findings at surgical exploration.

RESULTS

For each reviewer, the overall accuracy rates for predicting involvement of the bilateral secondary biliary confluences and the intrapancreatic CBD were 90.7% and 87.0% for MRI with MRCP and 85.1% and 87.0% for MDCT with direct cholangiography. The differences were not statistically significant for either image set for either reviewer (p > 0.05). In the assessment of vascular involvement, lymph node metastasis, and tumor resectability, the readers' diagnostic performance using MRI with MRCP was similar to that with MDCT with direct cholangiography (p > 0.05).

CONCLUSION

In the diagnosis of bile duct cancer with a noninvasive procedure, the information regarding tumor extent and resectability obtained with contrast-enhanced MRI combined with MRCP is comparable with that obtained with MDCT with direct cholangiography.

Contrast-enhanced MRI combined with MR cholangiopancreatography for the evaluation of patients with biliary strictures: differentiation of malignant from benign bile duct strictures

PURPOSE

To determine imaging criteria for the combined use of contrast-enhanced (CE)-MRI and MR cholangiopancreatography (MRCP) to differentiate malignant from benign biliary strictures.

MATERIALS AND METHODS

A total of 44 patients with biliary stricture who had undergone unenhanced, MRCP, and dynamic MRI were identified from radiological and surgical databases. Two radiologists analyzed MR features for asymmetry, luminal irregularity, abrupt narrowing, outer margin, signal intensity (SI) on T2-weighted (T2W) images, and hyperenhancement relative to liver parenchyma during portal phase. The wall thickness and length of the narrowed segment were measured. MR findings relevant as predictors were identified using a Chi-square or Fisher's exact test and the odds ratio (OR).

RESULTS

The presence of hyperenhancement relative to liver parenchyma, length > 12 mm, wall thickness > 3 mm, indistinct outer margin, luminal irregularity, and asymmetry of strictured bile duct were significant factors for malignancy (P < 0.05). Malignant strictures were significantly thicker (5.0 +/- 2.0 mm) and longer (27.0 +/- 13.6 mm) than benign strictures. When any three or more of these six criteria were used in combination, we could identify 100% of malignant strictures and 87.0% of benign strictures.

CONCLUSION

The combined use of CE-MRI and MRCP helped to define the criteria for differentiating malignant from benign biliary strictures in our data.

Pancreatic imaging: current and emerging technologies

This review discusses the current imaging modalities for the diagnosis and staging of solid and cystic pancreatic lesions and for the assessment of acute and chronic pancreatitis, and the future role of emerging technologies in the management of pancreatic diseases. Multidetector row spiral computed tomography is superior to conventional single-detector row spiral computed tomography in the detection and staging of pancreatic adenocarcinoma. Positron emission tomography is a sensitive but relatively nonspecific diagnostic modality. Positron emission tomography-computed tomography fusion may improve the staging accuracy for pancreatic cancer. Echo-enhanced ultrasound may have an emerging role in evaluating pancreatic masses. Endoscopic ultrasound with fine needle aspiration for cytology is the single best method for diagnosis and staging of nonmetastatic pancreatic cancer with a high accuracy for determining tumor resectability. In acute pancreatitis, a modification of the standard computed tomography severity index, which places greater emphasis on extrapancreatic complications, has shown superior correlation with various patient outcome measures. Endoscopic retrograde cholangiopancreatography is still the test of choice for morphological evaluation of chronic pancreatitis, whereas magnetic resonance cholangiopancreatography offers a noninvasive alternative in selected patients. Endoscopic ultrasound can be useful for detecting early chronic pancreatitis. Secretin-stimulated imaging techniques may eventually provide a noninvasive method of reliably assessing pancreatic exocrine function.