Gadobutrol-enhanced, three-dimensional, dynamic MR imaging with MR cholangiography for the preoperative evaluation of bile duct cancer. Invest Radiol. 2010;45:217-224. [PMID: 20195160 DOI: 10.1097/rli.0b013e3181d2eeb1]

Preoperative CT and MRI assessment of the longitudinal tumor extent of extrahepatic bile duct cancer after biliary drainage

PURPOSE

To examine the diagnostic performance for the longitudinal extent of extrahepatic bile duct (EHD) cancer on computed tomography (CT) after biliary drainage (BD) and investigate the appropriate timing of magnetic resonance imaging (MRI) acquisition.

METHODS

This retrospective study included patients who underwent curative-intent surgery for EHD cancer and CT pre- and post-BD between November 2005 and June 2021. The biliary segment-wise longitudinal tumor extent was evaluated according to the 2019 Korean Society of Abdominal Radiology consensus recommendations, with pre-BD CT, post-BD CT, and both pre- and post-BD CT. The performance for tumor detectability was compared using generalized estimating equation (GEE) method. When preoperative MRI was performed, patients were divided into two subgroups according to the timing of MRI with respect to BD, and the performance of MRI obtained pre- and post-BD was compared.

RESULTS

In 105 patients (mean age: 67 ± 8 years; 74 men and 31 women), the performance for tumor detectability was superior using both CT scans compared with using post-BD CT alone (reader 1: sensitivity, 72.6% vs. 64.6%, P < 0.001; specificity, 96.9% vs. 94.8%, P = 0.063; reader 2: sensitivity, 77.2% vs. 72.9%, P = 0.126; specificity, 97.5% vs. 94.2%, P = 0.003), and it was comparable with using pre-BD CT alone. In biliary segments with a catheter, higher sensitivity and specificity were observed using both CT scans than using post-BD CT (reader 1: sensitivity, 74.4% vs. 67.5%, P = 0.006; specificity, 92.4% vs. 88.0%, P = 0.068; reader 2: sensitivity, 80.5% vs. 74.4%, P = 0.013; specificity, 94.3% vs. 88.0%, P = 0.016). Post-BD MRI (n = 30) exhibited a comparable performance to pre-BD MRI (n = 55) (reader 1: sensitivity, 77.9% vs. 75.0%, P = 0.605; specificity, 97.2% vs. 94.9%, P = 0.256; reader 2: sensitivity, 73.2% vs. 72.6%, P = 0.926; specificity, 98.4% vs. 94.9%, P = 0.068).

CONCLUSION

Pre-BD CT provided better diagnostic performance in the preoperative evaluation of EHD cancer. The longitudinal tumor extent could be accurately assessed with post-BD MRI, which was similar to pre-BD MRI.

CLINICAL SIGNIFICANCE

The acquisition of pre-BD CT could be beneficial for the preoperative evaluation of EHD cancer when BD is planned. Post-BD MRI would not be significantly affected by BD in terms of the diagnostic performance of the longitudinal tumor extent.

Practice guidelines for managing extrahepatic biliary tract cancers

Backgrounds/Aims

Reported incidence of extrahepatic bile duct cancer is higher in Asians than in Western populations. Korea, in particular, is one of the countries with the highest incidence rates of extrahepatic bile duct cancer in the world. Although research and innovative therapeutic modalities for extrahepatic bile duct cancer are emerging, clinical guidelines are currently unavailable in Korea. The Korean Society of Hepato-Biliary-Pancreatic Surgery in collaboration with related societies (Korean Pancreatic and Biliary Surgery Society, Korean Society of Abdominal Radiology, Korean Society of Medical Oncology, Korean Society of Radiation Oncology, Korean Society of Pathologists, and Korean Society of Nuclear Medicine) decided to establish clinical guideline for extrahepatic bile duct cancer in June 2021.

Methods

Contents of the guidelines were developed through subgroup meetings for each key question and a preliminary draft was finalized through a Clinical Guidelines Committee workshop.

Results

In November 2021, the finalized draft was presented for public scrutiny during a formal hearing.

Conclusions

The extrahepatic guideline committee believed that this guideline could be helpful in the treatment of patients.

Clinical Efficacy of Gadobutrol: Review of Over 25 Years of Use Exceeding 100 Million Administrations

BACKGROUND

Gadobutrol has been administered more than 100 million times worldwide, since February 1998, that is, over the last 25 years. Numerous clinical studies in a broad range of indications document the long-term experience with gadobutrol.

OBJECTIVE

The aim of this study was to provide a literature-based overview on gadobutrol's efficacy in 9 approved indications and use in children.

MATERIALS AND METHODS

Efficacy results in patients of all age groups including sensitivity, specificity, accuracy, and positive/negative predictive values were identified by a systematic literature search on Embase until December 31, 2022. Nine approved indications were considered: central nervous system (CNS), magnetic resonance angiography (MRA), breast, heart, prostate, kidney, liver, musculoskeletal, whole body, and various indications in children.

RESULTS

Sixty-five publications (10 phase III, 2 phase IV, 53 investigator-initiated studies) reported diagnostic efficacy results obtained from 7806 patients including 271 children, at 369 centers worldwide. Indication-specific sensitivity ranges were 59%-98% (CNS), 53%-100% (MRA), 80%-100% (breast), 64%-90% (heart), 64%-96% (prostate), 71-85 (kidney), 79%-100% (liver), 53%-98% (musculoskeletal), and 78%-100% (children). Indication-specific specificity ranges were 75%-100% (CNS), 64%-99% (MRA), 58%-98% (breast), and 47%-100% (heart).

CONCLUSIONS

The evaluated body of evidence, consisting of 65 studies with 7806 patients, including 271 children and 7535 adults, showed that gadobutrol is an efficacious magnetic resonance imaging contrast agent for all age groups in various approved indications throughout the whole body.

British Society of Gastroenterology guidelines for the diagnosis and management of cholangiocarcinoma

These guidelines for the diagnosis and management of cholangiocarcinoma (CCA) were commissioned by the British Society of Gastroenterology liver section. The guideline writing committee included a multidisciplinary team of experts from various specialties involved in the management of CCA, as well as patient/public representatives from AMMF (the Cholangiocarcinoma Charity) and PSC Support. Quality of evidence is presented using the Appraisal of Guidelines for Research and Evaluation (AGREE II) format. The recommendations arising are to be used as guidance rather than as a strict protocol-based reference, as the management of patients with CCA is often complex and always requires individual patient-centred considerations.

Comparison Between Contrast-Enhanced Computed Tomography and Contrast-Enhanced Magnetic Resonance Imaging With Magnetic Resonance Cholangiopancreatography for Resectability Assessment in Extrahepatic Cholangiocarcinoma

OBJECTIVE

To compare the diagnostic performance and interobserver agreement between contrast-enhanced computed tomography (CECT) and contrast-enhanced magnetic resonance imaging (CE-MRI) with magnetic resonance cholangiopancreatography (MRCP) for evaluating the resectability in patients with extrahepatic cholangiocarcinoma (eCCA).

MATERIALS AND METHODS

This retrospective study included treatment-naïve patients with pathologically confirmed eCCA, who underwent both CECT and CE-MRI with MRCP using extracellular contrast media between January 2015 and December 2020. Among the 214 patients (146 males; mean age ± standard deviation, 68 ± 9 years) included, 121 (56.5%) had perihilar cholangiocarcinoma. R0 resection was achieved in 108 of the 153 (70.6%) patients who underwent curative-intent surgery. Four fellowship-trained radiologists independently reviewed the findings of both CECT and CE-MRI with MRCP to assess the local tumor extent and distant metastasis for determining resectability. The pooled area under the receiver operating characteristic curve (AUC), sensitivity, and specificity of CECT and CE-MRI with MRCP were compared using clinical, surgical, and pathological findings as reference standards. The interobserver agreement of resectability was evaluated using Fleiss kappa (κ).

RESULTS

No significant differences were observed between CECT and CE-MRI with MRCP in the pooled AUC (0.753 vs. 0.767), sensitivity (84.7% [366/432] vs. 90.3% [390/432]), and specificity (52.6% [223/424] vs. 51.4% [218/424]) (P > 0.05 for all). The AUC for determining resectability was higher when CECT and CE-MRI with MRCP were reviewed together than when CECT was reviewed alone in patients with discrepancies between the imaging modalities or with indeterminate resectability (0.798 [0.754-0.841] vs. 0.753 [0.697-0.808], P = 0.014). The interobserver agreement for overall resectability was fair for both CECT (κ = 0.323) and CE-MRI with MRCP (κ = 0.320), without a significant difference (P = 0.884).

CONCLUSION

CECT and CE-MRI with MRCP showed no significant differences in the diagnostic performance and interobserver agreement in determining the resectability in patients with eCCA.

Multidetector CT of Extrahepatic Bile Duct Cancer: Diagnostic Performance of Tumor Resectability and Interreader Agreement

Background In extrahepatic bile duct (EHD) cancer, accurate assessment of resectability is essential for curative surgery, but pertinent guidelines from the perspectives of radiologists are yet to be developed. Purpose To investigate the performance of multiphasic CT in the assessment of longitudinal tumor extent, vascular invasion, and resectability of EHD cancer according to the Korean Society of Abdominal Radiology consensus recommendation and to evaluate the interreader agreement. Materials and Methods This retrospective study included patients with EHD cancer who underwent multiphasic CT examinations with section thickness of 3 mm or less before surgery from January 2016 to December 2018. Four abdominal radiologists independently evaluated the overall and biliary segment-wise longitudinal tumor extent, the presence of hepatic artery and/or portal vein invasion, and the resectability according to the Korean Society of Abdominal Radiology recommendations. The diagnostic performance was assessed with sensitivity, specificity, accuracy, and area under the receiver operating characteristic curve. Interreader agreement was determined using κ statistics. Results A total of 112 patients (mean age ± SD, 61 years ± 11; 73 men) were evaluated. The accuracy of the overall longitudinal tumor extent assessment ranged from 56.3% (63 of 112 patients) to 74.1% (83 of 112 patients). The sensitivity for detecting secondary confluence involvement (n = 62) was lower than that for the primary confluence or intrapancreatic duct (n = 115; 38.5%-75% vs 72.1%-96.3%, respectively). Vascular invasion (n = 17) had moderate sensitivity (28.6%-71.4%) and high specificity (77.5%-99.0%). For predicting negative-margin (R0) resection (n = 85), the sensitivity and specificity ranged from 71.8% to 96.5% and from 11.1% to 66.7%, respectively, and the areas under the receiver operating characteristic curve ranged from 0.69 to 0.80. Interreader agreements for tumor extent, vascular invasion, and resectability had κ values of 0.65-0.89, 0.21-0.64, and 0.35-0.56, respectively. Conclusion For the preoperative evaluation of extrahepatic bile duct cancer, the Korean Society of Abdominal Radiology consensus recommendation enabled systematic assessment of longitudinal tumor extent and vascular invasion with acceptable performance in predicting negative-margin resection with use of multiphasic CT and with fair to good interreader agreement. © RSNA, 2022 Online supplemental material is available for this article.

Prediction of prognosis and resectability using MR imaging, clinical, and histopathological findings in patients with perihilar cholangiocarcinoma

PURPOSE

To predict poor overall survival (OS) and risk of residual tumor after surgery using MR imaging, clinical, and histopathological findings in perihilar cholangiocarcinoma.

METHODS

196 patients with perihilar cholangiocarcinoma who underwent preoperative MRI and curative-intent surgery were retrospectively included. MRI findings were assessed by two radiologists. Clinical characteristics and histopathological results such as serum carcinoembryonic antigen (CEA), carbohydrate antigen 19-9 (CA 19-9), T and N stage, and resection status, were also investigated. Cox regression analysis and the Kaplan-Meier method were used to identify prognostic factors for OS. We further analyzed the correlation between MRI features and residual tumors using logistic regression analysis.

RESULTS

The median OS was 25.0 ± 26.6 months. T stage (hazard ratio [HR] 6.26, p = 0.014), N stage (HR 1.86, p = 0.002), CA-19-9 >37 U/mL (HR 2.06, p < 0.001), enlarged LN on MRI (HR 1.69, p = 0.006), and residual tumor (HR 1.52, p = 0.034) were important predictors of poor survival. The 5-year OS of the complete resection group (n = 107) was significantly better than that of the residual tumor group (n = 89) (35.5% vs. 18.8%, p = 0.002). Additionally, peritumoral fat stranding (odds ratio[OR] 2.09, p = 0.027), Bismuth type III/IV (OR 1.95, p = 0.022), and common bile duct (CBD) involvement (OR 2.3, p = 0.008) on MRI were important predictors of residual tumors in univariate analyses. However, absence of peritumoral fat stranding was a significant independent predictor for complete resection (OR 1.99, p = 0.048) and showed the highest sensitivity, at 79.8%.

CONCLUSION

MR imaging, clinical and histopathological results are useful for predicting poor survival after surgery for perihilar cholangiocarcinoma. Furthermore, MRI findings, including peritumoral fat stranding, CBD involvement, and Bismuth type, are important for the prediction of residual tumors.

Abdominal Organ Enhancement in Dynamic MRI using 1 M Gadobutrol vs 0.5 M Meglumine Gadoterate in Liver of Hemangioma Patients

BACKGROUND

The utility of gadobutrol (GAD) which is higher r1 value contrast media for evaluating abdominal solid organ have not been fully evaluated.

OBJECTIVE

To compare the contrast enhancement of abdominal organs on dynamic MRI using 0.1 mmol/kg 1.0 M GAD or 0.5 M meglumine gadoterate (MG) in patients with a liver hemangioma.

METHODS

A phantom study was performed at different concentrations (0.05, 0.1, 0.3, 0.5, 0.7, 0.9, 1.0, 5.0 and 10 mmol/L) of GAD and MG. Sixty-two patients with a liver hemangioma were enrolled. Contrast media was injected at a rate of 2 mL/s followed by 40 mL of saline. Two arterial phases, a portal phase and an equilibrium phase were obtained. One certified radiologist set regions of interest on the abdominal aorta, liver, pancreas, spleen and the liver hemangioma. The relative enhancement ratio (RER) was calculated.

RESULTS

In the phantom study the signal intensity of both contrast media was similar at lower concentrations. However, the signal intensity of MG was higher at concentrations of more than 5.0 mmol/L. In the clinical study the RER of the abdominal viscera during the portal and equilibrium phases was higher with GAD. The hemangioma had a higher equilibrium phase enhancement with GAD. The aortic RER was equivalent during all phases and the liver RER during the 2nd arterial phase was higher with GAD. The arterial phase during GAD imaging might have been measured later than was optimal.

CONCLUSION

When the same injection protocol was used for an abdominal dynamic MRI, arterial phase imaging was late when GAD was used. The higher T1 relaxation value was significantly higher in the abdominal viscera during the portal and equilibrium phases, while the liver hemangioma also had significantly higher contrast enhancement during the equilibrium phase.

CLINICAL TRIAL REGISTRATION NUMBER

3186.

Assessment of Malignancy Potential in Intraductal Papillary Mucinous Neoplasms of the Pancreas on MDCT

RATIONALE AND OBJECTIVE

To assess the malignancy potential of intraduct papillary mucinous neoplasms (IPMNs) on multidetector-row computerized tomography according to the 2012 International Consensus Guidelines (ICG).

MATERIALS AND METHODS

This study retrospectively collected IPMNs confirmed by surgery from 2016 to 2019. The imaging findings of IPMNs were analyzed. IPMNs were classified as malignancy in the presence of high-grade dysplasia or invasive carcinoma and began in the presence of low- and intermediate-grade dysplasia.

RESULTS

A total of 207 patients (mean age: 63.7 ± 7.9 years) were included, and the prevalence of malignancy was 28.0% (58 of 207). According to the 2012 ICG, the imaging findings of IPMNs were divided into worrisome features (WFs) and high-risk stigmata (HRS). The malignancy of IPMN with only one WF was relatively low (1.4%, 3 of 207). In multivariate regression analyses, the independent factors of IPMNs were enhanced mural nodule ≥5 mm (odds ratio [OR] = 19.5, 95% confidence interval [CI] 6.8-55.4), abrupt change in the main pancreatic duct caliber with distal pancreatic atrophy (OR = 4.6, 95%CI 1.67-12.71), and thickened enhanced cyst walls (OR = 2.9, 95%CI 1.1-8.2). When the presence of more than two WFs or HRS (score ≥ 3) was regarded as indicating the malignancy potential of IPMNs on multidetector-row computerized tomography, the sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) were 89.7%, 75.8%, 79.7%, 59.1%, and 95.0%, respectively.

CONCLUSION

According to the ICG in 2012, patients with IPMNs with only one WF have a low risk for malignancy, and the presence of at least two WFs or any HRS (score ≥3) suggests malignant IPMNs.

Additional Value of Integrated 18F-FDG PET/MRI for Evaluating Biliary Tract Cancer: Comparison with Contrast-Enhanced CT

Objective

To evaluate the value of ¹⁸F-fluorodeoxyglucose PET/MRI added to contrast-enhanced CT (CECT) in initial staging, assessment of resectability, and postoperative follow-up of biliary tract cancer.

Materials and Methods

This retrospective study included 100 patients (initial workup [n = 65] and postoperative follow-up [n = 35]) who had undergone PET/MRI and CECT for bile duct or gallbladder lesions between January 2013 and March 2020. Two radiologists independently reviewed the CECT imaging set and CECT plus PET/MRI set to determine the likelihood of malignancy, local and overall resectability, and distant metastasis in the initial workup group, and local recurrence and distant metastasis in the follow-up group. Diagnostic performances of the two imaging sets were compared using clinical-surgical-pathologic findings as standards of reference.

Results

The diagnostic performance of CECT significantly improved after the addition of PET/MRI for liver metastasis (area under the receiver operating characteristic curve [A_z]: 0.77 vs. 0.91 [p = 0.027] for reviewer 1; 0.76 vs. 0.92 [p = 0.021] for reviewer 2), lymph node metastasis (0.73 vs. 0.92 [p = 0.004]; 0.81 vs. 0.92 [p = 0.023]), and overall resectability (0.79 vs. 0.92 [p = 0.007]; 0.82 vs. 0.94 [p = 0.021]) in the initial workup group. In the follow-up group, the diagnostic performance of CECT plus PET/MRI was significantly higher than that of CECT imaging for local recurrence (0.81 vs. 1.00 [p = 0.029]; 0.82 vs. 0.94 [p = 0.045]).

Conclusion

PET/MRI may add value to CECT in patients with biliary tract cancer both in the initial workup for staging and determination of overall resectability and in follow-up for local recurrence.

Current Status and Recent Update of Imaging Evaluation for Peri-Hilar Cholangiocarcinoma

간문주변부의 해부학적 복잡성으로 인해 간문주변부 담관암은 그 진단과 치료가 어려운 질환으로 알려져 있다. 간문주변부 담관암이 의심되는 환자에 있어서, 영상 검사는 이상 소견의 발견 및 감별 진단, 종양의 종축 침범 부위의 파악, 인접 혈관 침범과 원격 전이 유무의 파악, 그리고 최종적으로 수술적 절제 가능 유무의 평가에 있어 핵심적인 역할을 하고 있다. 이 종설에서는 간문주변부 담관암의 분류 및 종양의 평가를 위해 권고되는 표준 영상 검사의 기법과 간문주변부 담관암의 전형적인 영상 소견에 대해 기술할 예정이다. 종축 방향의 종양 침범 파악, 인접 혈관 침범 및 원격 전이 유무의 평가에 있어서 각 영상 검사 소견과 그 진단능에 대해 논의할 예정이다. 이후 전통적인 절제 가능성 평가의 개념에 대해 고찰하고, 최근의 경향을 소개한다.

Hindman NM, Arif-Tiwari H, Kamel IR, Al-Refaie WB, Bartel TB, Cash BD, Chernyak V, Goldstein A, Grajo JR, Horowitz JM, Kamaya A, McNamara MM, Porter KK, Srivastava PK, Zaheer A, Carucci LR. ACR Appropriateness Criteria® Jaundice

Jaundice is the end result of myriad causes, which makes the role of imaging in this setting particularly challenging. In the United States, the most common causes of all types of jaundice fall into four categories including hepatitis, alcoholic liver disease, blockage of the common bile duct by a gallstone or tumor, and toxic reaction to a drug or medicinal herb. Clinically, differentiating between the various potential etiologies of jaundice requires a detailed history, targeted physical examination, and pertinent laboratory studies, the results of which allow the physician to categorize the type of jaundice into mechanical or nonmechanical causes. Imaging modalities used to evaluate the jaundiced patient (all etiologies) include abdominal ultrasound (US), CT, MR cholangiopancreatography, endoscopic retrograde cholangiopancreatography and endoscopic US. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Radiologic Evaluation and Structured Reporting Form for Extrahepatic Bile Duct Cancer: 2019 Consensus Recommendations from the Korean Society of Abdominal Radiology

Radiologic imaging is important for evaluating extrahepatic bile duct (EHD) cancers; it is used for staging tumors and evaluating the suitability of surgical resection, as surgery may be contraindicated in some cases regardless of tumor stage. However, the published general recommendations for EHD cancer and recommendations guided by the perspectives of radiologists are limited. The Korean Society of Abdominal Radiology (KSAR) study group for EHD cancer developed key questions and corresponding recommendations for the radiologic evaluation of EHD cancer and organized them into 4 sections: nomenclature and definition, imaging technique, cancer evaluation, and tumor response. A structured reporting form was also developed to allow the progressive accumulation of standardized data, which will facilitate multicenter studies and contribute more evidence for the development of recommendations.

Progress in diagnosis and surgical treatment of perihilar cholangiocarcinoma

Cholangiocarcinomas are heterogeneous biliary tract tumors that cause devastating disease. Perihilar cholangiocarcinoma (PHC) is the most common type of biliary tract cancer and are associated with a high mortality. Diagnoses of PHC depend on the results of its clinical presentation, serum biomarkers and imaging techniques. Pre-operative managements including pre-operative biliary drainage (PBD) and portal vein embolization (PVE) could reduce mortality. The best chance of long-term survival and potential cure is surgical resection with negative surgical margin. Lymph node metastasis over N2 nodes precludes long-term survival. The benefit of concomitant vascular resection remains uncertain. Liver transplantation combined with neoadjuvant chemotherapy with radiotherapy is a promising option in highly selected patients with unresectable tumors. Herein, an overview is provided of developments in diagnosis, peri-operative management and surgical treatment among patients with PHCs.

The diagnostic accuracy of CT and MRI for the detection of lymph node metastases in gallbladder cancer: A systematic review and meta-analysis

BACKGROUND

Lymph node metastases (LNM) are an ominous prognostic factor in gallbladder cancer (GBC) and, when present, should preclude surgery. However, uncertainty remains regarding the optimal imaging modality for pre-operative detection of LNM and international guidelines vary in their recommendations. The purpose of this study was to systematically review the diagnostic accuracy of computed tomography (CT) versus magnetic resonance imaging (MRI) in the detection of LNM of GBC.

METHODS

A literature search of studies published until November 2017 concerning the diagnostic accuracy of CT or MRI regarding the detection of LNM in GBC was performed. Data extraction and risk of bias assessment was performed independently by two reviewers. The sensitivity of CT and MRI in the detection of LNM was reviewed. Additionally, estimated summary sensitivity, specificity and diagnostic accuracy of MRI were calculated in a patient based meta-analysis.

RESULTS

Nine studies including 292 patients were included for narrative synthesis and 5 studies including 158 patients were selected for meta-analysis. Sensitivity of CT ranged from 0.25 to 0.93. Estimated summary diagnostic accuracy parameters of MRI were as follows: sensitivity 0.75 (95% CI 0.6 - 0.85), specificity 0.83 (95% CI 0.74 - 0.90), LR + 4.52 (95% CI 2.55-6.48) and LR- 0.3 (95% CI 0.15 - 0.45). Small (<10 mm) LNM were most frequently undetected on pre-operative imaging. Due to a lack of data, no subgroup analysis comparing the diagnostic accuracy of CT versus MRI could be performed.

CONCLUSION

The value of current imaging strategies for the pre-operative assessment of nodal status in GBC remains unclear, especially regarding the detection of small LNM. Additional research is warranted in order to establish uniformity in international guidelines, improve pre-operative nodal staging and to prevent futile surgery.

Diagnostic accuracy of magnetic resonance, computed tomography and contrast enhanced ultrasound in radiological multimodality assessment of peribiliary liver metastases

PURPOSE

We compared diagnostic performance of Magnetic Resonance (MR), Computed Tomography (CT) and Ultrasound (US) with (CEUS) and without contrast medium to identify peribiliary metastasis.

METHODS

We identified 35 subjects with histological proven peribiliary metastases who underwent CEUS, CT and MR study. Four radiologists evaluated the presence of peribiliary lesions, using a 4-point confidence scale. Echogenicity, density and T1-Weigthed (T1-W), T2-W and Diffusion Weighted Imaging (DWI) signal intensity as well as the enhancement pattern during contrast studies on CEUS, CT and MR so as hepatobiliary-phase on MRI was assessed.

RESULTS

All lesions were detected by MR. CT detected 8 lesions, while US/CEUS detected one lesion. According to the site of the lesion, respect to the bile duct and hepatic parenchyma: 19 (54.3%) were periductal, 15 (42.8%) were intra-periductal and 1 (2.8%) was periductal-intrahepatic. According to the confidence scale MRI had the best diagnostic performance to assess the lesion. CT obtained lower diagnostic performance. There was no significant difference in MR signal intensity and contrast enhancement among all metastases (p>0.05). There was no significant difference in CT density and contrast enhancement among all metastases (p>0.05).

CONCLUSIONS

MRI is the method of choice for biliary tract tumors but it does not allow a correct differential diagnosis among different histological types of metastasis. The presence of biliary tree dilatation without hepatic lesions on CT and US/CEUS study may be an indirect sign of peribiliary metastases and for this reason the patient should be evaluated by MRI.

Preoperative Radiologic Evaluation of Cholangiocarcinoma

In patients with cholangiocarcinoma, surgical resection with curative intent is the only way to achieve cure. Since surgical resection of cholangiocarcinomas is technically demanding, determination of resectability and accurate preoperative staging are crucial. For these purposes, high quality imaging including multidetector computed tomography and magnetic resonance imaging with magnetic resonance cholangiopancreaticography, is mandatory. This article will present recent advances in imaging techniques for cholangiocarginomas, potential pitfalls in imaging evaluation, and a checklist for preoperative radiologic assessment of resectability in these patients with an emphasis on perihilar cholangiocarinoma.

Relationship between the surgical margin status, prognosis, and recurrence in extrahepatic bile duct cancer patients

PURPOSE

The purpose of this retrospective study was to evaluate the relationship between the surgical margin status of the bile duct and the prognosis and recurrence of extrahepatic bile duct (EHBD) cancer.

METHODS

The clinical data of 100 patients who underwent surgery for EHBD cancer between February 2002 and September 2014 were analyzed. The ductal margin status was classified into the following three categories: negative (D-N), positive with carcinoma in situ (D-CIS), and positive with invasive carcinoma (D-INV).

RESULTS

The number of patients with D-N, D-CIS, and D-INV was 69, 16, and 15, respectively. Local recurrence rates of patients with D-CIS (56.3 %) and D-INV (66.7 %) were significantly higher compared to those of patients with D-N (10.1 %; P < 0.001). D-CIS was a significant predictor of shorter recurrence-free survival (RFS). Lymph node metastasis (P = 0.037) and D-INV (P = 0.008) were independent predictors of shorter disease-specific survival (DSS). The prognostic relevance of the ductal margin status was high, particularly in patients without lymph node metastasis.

CONCLUSION

The surgical margin status of the bile duct was significantly associated with RFS, DSS, and the recurrence site.

Radiological Imaging for Assessing the Respectability of Hilar Cholangiocarcinoma: A Systematic Review and Meta-Analysis

Hilar cholangiocarcinoma (HCC) remains one of the most difficult tumors to stage and treat. The aim of the study was to assess the diagnostic efficiency of computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography/computer tomography (PET/CT) in evaluating the resectability of HCC. A systematic search was performed of the PubMed, EMBASE, and Cochrane databases. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy were calculated for individual studies and pooled data as well as test for heterogeneity and public bias. Our data showed that CT had the highest pooled sensitivity at 95% (95% CI: 91-97), whereas PET/CT had the highest pooled specificity at 81% (95% CI: 69-90). The area under the curve (AUC) of CT, MRI, and PET/CT was 0.9269, 0.9194, and 0.9218, respectively. In conclusion, CT is the most frequently used imaging modality to assess HCC resectability with a good sensitivity and specificity. MRI was generally comparable with that of CT and can be used as an alternative imaging technique. PET/CT appears to be the best technique in detecting lymph node and distant metastasis in HCC but has no clear role in helping to evaluate issues of local resectability.

Value of diffusion-weighted MRI for differentiating malignant from benign intraductal papillary mucinous neoplasms of the pancreas

OBJECTIVE

The purpose of this study was to evaluate whether the use of diffusion-weighted MRI (DWI) increases diagnostic accuracy in the differentiation of malignant from benign intraductal papillary mucinous neoplasms (IPMNs) of the pancreas over the accuracy of contrast-enhanced MRI with MRCP.

MATERIALS AND METHODS

A total of 61 patients with surgically resected IPMNs (19 malignant, 42 benign) who underwent gadoxetic acid-enhanced MRI, DWI, and MRCP were included. Two blinded observers evaluated two image sets, that is, conventional MRI with MRCP images versus combined conventional MRI with MRCP and DW images, and scored their confidence for malignancy of IPMNs. Qualitative analyses of the IPMNs were also conducted. Diagnostic performance (ROC curve analysis), accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were evaluated. The Fisher exact test was used to compare groups.

RESULTS

The diagnostic performance (area under the ROC curve [Az]) with respect to predicting malignancy of IPMNs improved significantly for both observers after additional review of DW images (p < 0.05). The diagnostic accuracy, sensitivity, specificity, PPV, and NPV of combined conventional and DW images were higher than those of conventional MR images alone. Diffusion restriction was more often present in malignant IPMNs (78.9%) than in benign IPMNs (16.7%) (p < 0.001) with excellent interobserver agreement (ĸ = 0.965).

CONCLUSION

Compared with conventional MRI alone, adding DWI to conventional MRI improves diagnostic accuracy with increased specificity for differentiating malignant from benign IPMNs of the pancreas.

MRI of cholangiocarcinoma

Cholangiocarcinomas are the second most common primary hepatobiliary tumors after hepatocellular carcinomas. They can be categorized either based on their location (intrahepatic/perihilar/extrahepatic distal) or their growth characteristics (mass-forming/periductal-infiltrating/intraductal) because they exhibit varied presentations and outcomes based on their location and or pattern of growth. The increased risk of cholangiocarcinoma in PSC necessitates close surveillance of these patients by means of imaging and laboratory measures; and because currently surgical resection is the only effective treatment for cholangiocarcinoma, the need for accurate pre-operative staging and assessment of resectability has emphasized the role of high quality imaging in management. Today magnetic resonance imaging (MRI) is the modality of choice for detection, pre-operative staging and surveillance of cholangiocarcinoma.

Comparison of different magnetic resonance cholangiography techniques in living liver donors including Gd-EOB-DTPA enhanced T1-weighted sequences

Objectives

Preoperative evaluation of potential living liver donors (PLLDs) includes the assessment of the biliary anatomy to avoid postoperative complications. Aim of this study was to compare T2-weighted (T2w) and Gd-EOB-DTPA enhanced T1-weighted (T1w) magnetic resonance cholangiography (MRC) techniques in the evaluation of PLLDs.

Materials and Methods

30 PLLDs underwent MRC on a 1.5 T Magnetom Avanto (Siemens, Erlangen, Germany) using (A) 2D T2w HASTE (Half Fourier Acquisition Single Shot Turbo Spin Echo) fat saturated (fs) in axial plane, (B) 2D T2w HASTE fs thick slices in coronal plane, (C) free breathing 3D T2w TSE (turbo spin echo) RESTORE (high-resolution navigator corrected) plus (D) maximum intensity projections (MIPs), (E) T2w SPACE (sampling perfection with application optimized contrasts using different flip angle evolutions) plus (F) MIPs and (G) T2w TSE BLADE as well as Gd-EOB-DTPA T1w images without (G) and with (H) inversion recovery. Contrast enhanced CT cholangiography served as reference imaging modality. Two independent reviewers evaluated the biliary tract anatomy on a 5-point scale subjectively and objectively. Data sets were compared using a Mann-Whitney-U-test. Kappa values were also calculated.

Results

Source images and maximum intensity projections of 3D T2w TSE sequences (RESTORE and SPACE) proved to be best for subjective and objective evaluation directly followed by 2D HASTE sequences. Interobserver variabilities were good to excellent (k = 0.622–0.804).

Conclusions

3D T2w sequences are essential for preoperative biliary tract evaluation in potential living liver donors. Furthermore, our results underline the value of different MRCP sequence types for the evaluation of the biliary anatomy in PLLDs including Gd-EOB-DTPA enhanced T1w MRC.

Imaging bile duct tumors: pathologic concepts, classification, and early tumor detection

Cholangiocarcinoma is the most common primary malignancy of the bile ducts which has several predisposing factors such as hepatolithiasis and primary sclerosing cholangitis, and can develop from precancerous conditions such as biliary intraepithelial neoplasia and intraductal papillary neoplasm of the bile duct. As surgical resection of early stage cholangiocarcinoma or precancerous lesions may provide better prognosis, early detection of those lesions is very important. Imaging studies play important roles in the diagnosis of bile duct tumors followed by appropriate management. Indeed, not only diagnosis of cholangiocarcinoma but also appropriate categorization of bile duct tumors based on their morphologic features and location on cross-sectional imaging studies, including computed tomography and magnetic resonance imaging, is important to predict their biologic behaviors, and choose relevant treatment strategies. We herein review the classification system of the bile duct tumors with their radiologic and pathologic findings as well as role of imaging in the early detection of bile duct tumors.

Imaging diagnosis of pancreatic cancer: A state-of-the-art review

Pancreatic cancer (PC) remains one of the deadliest cancers worldwide, and has a poor, five-year survival rate of 5%. Although complete surgical resection is the only curative therapy for pancreatic cancer, less than 20% of newly-diagnosed patients undergo surgical resection with a curative intent. Due to the lack of early symptoms and the tendency of pancreatic adenocarcinoma to invade adjacent structures or to metastasize at an early stage, many patients with pancreatic cancer already have advanced disease at the time of their diagnosis and, therefore, there is a high mortality rate. To improve the patient survival rate, early detection of PC is critical. The diagnosis of PC relies on computed tomography (CT) and/or magnetic resonance imaging (MRI) with magnetic resonance cholangiopancreatography (MRCP), or biopsy or fine-needle aspiration using endoscopic ultrasound (EUS). Although multi-detector row computed tomography currently has a major role in the evaluation of PC, MRI with MRCP facilitates better detection of tumors at an early stage by allowing a comprehensive analysis of the morphological changes of the pancreas parenchyma and pancreatic duct. The diagnosis could be improved using positron emission tomography techniques in special conditions in which CT and EUS are not completely diagnostic. It is essential for clinicians to understand the advantages and disadvantages of the various pancreatic imaging modalities in order to be able to make optimal treatment and management decisions. Our study investigates the current role and innovative techniques of pancreatic imaging focused on the detection of pancreatic cancer.

Preoperative staging of gallbladder carcinoma using biliary MR imaging

PURPOSE

To evaluate the performance of biliary MRI, including unenhanced imaging, gadolinium-enhanced (Gd-E) dynamic imaging, and MR cholangiography, for the preoperative staging of gallbladder cancer (GBC).

MATERIALS AND METHODS

Our institutional review board approved this retrospective study. Eighty-six, consecutive patients with surgically resected and pathologically confirmed GBCs and who underwent preoperative MRI, including unenhanced T1- and T2-weighted images, MR cholangiography, and dynamic imaging, were enrolled in this study. Two observers independently evaluated the biliary MR images regarding the T- and N-staging of GBCs and graded their diagnostic confidence for the staging using a 5-point scale. Receiver operating curve analysis was performed to evaluate the diagnostic performance of MR in the staging of GBC. Interobserver agreement was evaluated using kappa statistics.

RESULTS

The overall accuracy of T- and N-staging using biliary MRI was 84.9% and 77.9% for observer 1 and 69.8% and 74.4% for observer 2. There was good interobserver agreement regarding the T stage (k = 0.828). The Az (AUC: area under the curve) values of the diagnostic ability of MRI to differentiate ≥ T1b from ≤ T1a lesions, were 0.979 and 0.955 for both observers (P < 0.0001).

CONCLUSION

Biliary MRI with MR cholangiography allows moderately accurate preoperative T staging and N staging of GBCs. It also shows an excellent diagnostic ability for differentiating ≥ T1b lesions from ≤ T1a lesions, which can be helpful for preoperative planning.

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.

Hilar cholangiocarcinoma: value of adding DW imaging to gadoxetic acid-enhanced MR imaging with MR cholangiopancreatography for preoperative evaluation

PURPOSE

To assess the benefit of adding diffusion-weighted (DW) imaging to gadoxetic acid-enhanced magnetic resonance (MR) imaging and MR cholangiopancreatography in the preoperative evaluation of hilar cholangiocarcinoma.

MATERIALS AND METHODS

The institutional review board approved this retrospective study and waived the requirement for informed consent. The study included 52 patients (36 men, 16 women; mean age, 63.4 years) with surgically confirmed hilar cholangiocarcinoma who underwent gadoxetic acid-enhanced MR imaging and DW imaging at 3.0 T between August 2010 and December 2011. Two observers independently reviewed two image sets--a gadoxetic acid set, including images from MR cholangiopancreatography, and a combined gadoxetic acid set and DW imaging set--to evaluate the tumor involvement of each biliary confluence and vascular and liver invasion by using receiver operating characteristic (ROC) curve analysis.

RESULTS

For each observer, area under the ROC curve (Az) values for tumor involvement of the biliary confluence were 0.965 and 0.957 for the gadoxetic acid set and 0.980 and 0.975 for the combined set, respectively (P > .05). For detecting 105 biliary confluences with tumor involvement, the sensitivities with the combined set (97.1% [102 of 105] and 98.1% [103 of 105]) were higher than those with the gadoxetic acid set (91.4% [96 of 105] for both observers) (P = .029 and P = .016), although the specificities were similar with both image sets (P > .05). For the detection of liver invasion, the combined set (75.0% [15 of 20] for both observers) yielded better sensitivity than the gadoxetic acid set (50.0% [10 of 20] and 45.0% [nine of 20]) (P = .016 and P = .031). For evaluation of vascular invasion, the two image sets showed similar diagnostic performance.

CONCLUSION

In the preoperative evaluation of hilar cholangiocarcinoma, the addition of DW imaging to gadoxetic acid-enhanced MR imaging could improve sensitivity in the evaluation of tumor extent along the bile duct and liver invasion.

A historical overview of magnetic resonance imaging, focusing on technological innovations

Magnetic resonance imaging (MRI) has now been used clinically for more than 30 years. Today, MRI serves as the primary diagnostic modality for many clinical problems. In this article, historical developments in the field of MRI will be discussed with a focus on technological innovations. Topics include the initial discoveries in nuclear magnetic resonance that allowed for the advent of MRI as well as the development of whole-body, high field strength, and open MRI systems. Dedicated imaging coils, basic pulse sequences, contrast-enhanced, and functional imaging techniques will also be discussed in a historical context. This article describes important technological innovations in the field of MRI, together with their clinical applicability today, providing critical insights into future developments.

Gadoxetic acid-enhanced MRI with MR cholangiography for the preoperative evaluation of bile duct cancer

PURPOSE

To assess the diagnostic accuracy of gadoxetic acid-enhanced biliary MRI with MR cholangiography (MRC) in the preoperative evaluation of bile duct cancer (BDC) staging and resectability.

MATERIALS AND METHODS

Seventy-three patients with BDC who underwent gadoxetic acid-enhanced biliary MRI and MRC, were included in this study. Two abdominal radiologists evaluated the biliary MRI findings regarding the tumor extent, vascular involvement, lymph node metastasis, and tumor resectability. The results were compared with the surgical and pathology findings which were used as the standard reference. The diagnostic performance of the MRI was evaluated using receiver operating characteristics (ROC) analysis. In addition, to determine whether the hepatobiliary phase images had been successfully obtained, the enhancement percentage of the hepatic parenchyma was measured on the portal venous images (PVI) and hepatobiliary phase images (HBPI), respectively.

RESULTS

The overall accuracy of the two reviewers for determining the tumor resectability was 61.6% and 83.5%, respectively. The Az values were 0.802 for reviewer 1 and 0.892 for reviewer 2 in the evaluation of the secondary biliary confluence tumor involvement and 0.773 for reviewer 1 and 0.846 for reviewer 2 in the evaluation of the intrapancreatic bile duct involvement. In the evaluation of the vascular involvement, the Az values were 0.718 and 0.906, respectively, for the hepatic artery evaluation and 0.55 and 0.88, respectively, for the portal vein evaluation. For assessment of lymph node metastasis, the overall accuracy was 69.6% and 79.7%, respectively. The mean enhancement percentages of hepatic parenchyma on PVI and HBPI were 39.3% and 65.9%, respectively (P % 0.05), and 49 of 73 patients (67.1%) showed higher enhancement percentage on HBPI than on PVI CONCLUSION: Gadoxetic acid-enhanced MRI with MRC is a reliable diagnostic method for assessing the tumor extent and resectability of BDC.

MRCP and 3D LAVA imaging of extrahepatic cholangiocarcinoma at 3 T MRI

Extrahepatic cholangiocarcinoma (CCA) is a primary bile duct malignant tumour with poor prognosis. Familiarity with their varied imaging characteristics can be helpful in developing a correct diagnosis and in optimal treatment planning, and thus contribute to a better prognosis. The purpose of this article is to illustrate the typical appearances of extrahepatic CCA on magnetic resonance cholangiopancreatography (MRCP) and three-dimensional (3D) LAVA (liver acquisition with volume acceleration) sequences at 3 T magnetic resonance imaging (MRI), and to discuss the superiority of the two techniques in the diagnosis of CCA.

Advances in diagnostic radiology

Recent advances in diagnostic radiology are discussed on the basis of current publications in Investigative Radiology. Publications in the journal during 2009 and 2010 are reviewed, evaluating developments by modality and anatomic region. Technological advances continue to play a major role in the evolution and clinical practice of diagnostic radiology, and as such constitute a major publication focus. In the past 2 years, this includes advances in both magnetic resonance and computed tomography (in particular, the advent of dual energy computed tomography). An additional major focus of publications concerns contrast media, and in particular continuing research involving nephrogenic systemic fibrosis, its etiology, and differentiation of the gadolinium chelates on the basis of in vivo stability.