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

Total laparoscopic radical resection of hilar cholangiocarcinoma: preliminary experience of a single center

BACKGROUND

The aim of this study was to describe our preliminary experience in the procedure of laparoscopic radical resection of hilar cholangiocarcinoma and to evaluate its feasibility, safety, and clinical efficacy.

METHODS

A retrospective analysis was conducted on 44 patients with hilar cholangiocarcinoma who underwent laparoscopic surgery at our hospital from August 2019 to September 2023. Clinical data were collected from these patients, including 13 cases of Bismuth type I, 17 cases of Bismuth type II, 5 cases of Bismuth type IIIa, and 9 cases of Bismuth type IIIb.

RESULTS

Laparoscopic radical resection of hilar cholangiocarcinoma was successfully performed in 38 patients (86.3%). Among the remaining patients, 3 required vascular reconstruction to complete radical surgery and were converted to laparotomies, while 3 others underwent T-tube drainage only due to unresectable metastases. The median operation time was 285 min (range, 190-450), and the median estimated blood loss was 360 mL (range, 260-1200). The postoperative hospital stay duration was 14.3 ± 3.6 days. No perioperative mortality was observed. Postoperative pathological examination revealed negative microscopic margins (R0) in 39 cases and positive microscopic margins (R1) in 2 cases. Postoperative complications occurred in 8 patients (18.1%), with 4 cases (9.0%) of Grade I, 3 cases (6.8%) of Grade II, 1 case (2.2%) of Grade IIIa, and no Grade IIIb or IV complications. The median overall survival for patients who underwent radical R0 resection was 30.4 months (range, 5.3-43.6). The Disease-free survival rates were 73.6% at 1 year, 61.2% at 2 years, and 40.1% at 3 years.

CONCLUSION

Total laparoscopic radical resection of hilar cholangiocarcinoma can be performed safely, feasibly, and effectively by experienced surgeons after an accurate preoperative evaluation.

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.

The value of contrast-enhanced magnetic resonance imaging for diagnosis of extrahepatic cholangiocarcinoma

Rationale and objectives

To establish a diagnostic model based on contrast-enhanced magnetic resonance imaging (MRI) and clinical characteristics for diagnosing extrahepatic cholangiocarcinoma (eCCA).

Materials and methods

From April 2014 to September 2021, consecutive patients with extrahepatic bile duct lesions who underwent contrast-enhanced MRI within 1 month before pathological examination were retrospectively enrolled. Two radiologists blinded to clinicopathological information independently evaluated MR images. Univariable and multivariable logistic regression analyses were performed to identify significant clinicoradiological features associated with eCCA, which were subsequently incorporated into a diagnostic model. Model performance was assessed using the area under the receiver operating characteristic curve (AUC), calibration curve, and decision curve.

Results

A total of 182 patients (mean age, 60.8 ± 10.0 years, 117 men) were included, 144 (79 %) of whom had pathologically confirmed eCCA. Diffusion restriction (odds ratio [OR], 8.32; 95 % confidence interval [CI]: 2.88, 25.82; P < 0.001), indistinct outer margin (OR, 4.01; 95 % CI: 1.40, 11.84; P = 0.010), cholelithiasis (OR, 0.34; 95 % CI: 0.12, 1.00; P = 0.049), serum ln(carbohydrate antigen 125) (OR, 4.95; 95 % CI: 1.61, 18.55; P = 0.010), and serum ln(direct bilirubin) (OR, 1.82; 95 % CI: 1.29, 2.63; P < 0.001) were independently associated with eCCA. Incorporating the above 5 variables, a diagnostic model achieved an AUC of 0.912 (95 % CI: 0.859, 0.965), with well-fitted calibration curve (P = 0.815) and good clinical utility. Additionally, the sensitivity, specificity and accuracy of the model were 83.33 %, 86.84 %, and 84.07 %, respectively.

Conclusion

The proposed model integrating two MRI features (i.e., indistinct outer margin and diffusion restriction) and three clinical characteristics (i.e., cholelithiasis, lnCA125 and lnDBIL) enabled accurate diagnosis of eCCA. This tool holds the potential to facilitate an early diagnosis and thereby allow timely treatment interventions and improved clinical outcomes for patients with eCCA.

Comparison of 18F-FDG PET/MR and PET/CT for pretreatment TNM staging of hilar cholangiocarcinoma

PURPOSE

18F-FDG PET/MR has been applied to the diagnosis and preoperative staging in various tumor types; however, reports using PET/MR in hilar cholangiocarcinoma (HCCA) are rare. We investigated the value of PET/MR for preoperative staging and compared it with PET/CT in HCCA.

METHODS

Fifty-eight patients with HCCA confirmed by pathology were retrospectively analyzed. 18F-FDG PET/CT imaging was performed first, followed with whole-body PET/MR imaging. SUVmax of tumor and normal liver tissue were measured. Paired T test was used to compare SUVmax of tumor and normal liver tissue of PET/CT and PET/MR. In addition, McNemar test was used to compare the accuracy of TNM staging and Bismuth-Corlette typing between PET/CT and PET/MR.

RESULTS

There was no significant difference in SUVmax between PET/CT and PET/MR in primary tumor lesions (6.6 ± 5.5 vs. 6.8 ± 6.2, P = 0.439). SUVmax of PET/CT and PET/MR in normal liver parenchyma was significantly different (3.0 ± 0.5 vs. 2.1 ± 0.5, P < 0.001). The accuracy of PET/MR in diagnosing T staging and N staging was significantly higher than those of PET/CT (72.4% vs. 58.6%, P = 0.022 and 84.5% vs. 67.2%, P = 0.002). There was no significant difference between PET/CT and PET/MR in M staging (94.8% vs. 98.3%, P = 0.5). The classification accuracy of PET/MR in Bismuth-Corlette was significantly higher than that of PET/CT (89.7% vs. 79.3%), P = 0.031.

CONCLUSIONS

The diagnostic accuracy of 18F-FDG PET/MR was superior to that of PET/CT in preoperative T staging, N staging, and Bismuth-Corlette classification of HCCA. In M staging, the diagnostic accuracy of PET/MR was similar to that of PET/CT.

The Evaluation of Zoomed Echo-Planar Diffusion-Weighted Magnetic Resonance Imaging With Two-dimensional Spatial-Selective Radiofrequency Excitation Pulses in Patients With Hilar Cholangiocarcinoma

Background

We aimed to investigate the feasibility and application of using the zoomed diffusion-weighted echo-planar imaging (z-EPI DWI) sequences for hilar cholangiocarcinoma assessment compared with conventional single-shot EPI diffusion-weighted imaging (c-EPI DWI).

Methods

Both c-EPI DWI and z-EPI DWI were preoperatively performed in 16 patients with histopathologically-confirmed hilar cholangiocarcinoma. A two-dimensional spatial-selective radiofrequency (RF) pulse was applied to the z-EPI DWI using an echo-planar transmit trajectory. Anatomic structural visualization, lesion conspicuity, artifact presence and overall image quality were evaluated and compared between the two sequence images. The ratio of differences regarding hilar cholangiocarcinoma lesion sizes measured on T2-weighted imaging (T₂WI) and diffusion-weighted imaging (DWI) were compared from both EPI techniques. The DW images for tumor involvement of the bile duct were reviewed based on histopathological examination of the surgical intraoperative evaluation. ADC measurements of DWIs in the hilar cholangiocarcinoma lesions were conducted.

Results

The hepatic hilar region was better delineated by visualization of anatomical structures, lesion conspicuity and overall image quality using the z-EPI DWI and these analyses were compared with the c-EPI DWI method (all p<0.05). Better lesion delineation of bile duct walls and lumens was noted in four patients with z-EPI DWI compared with those of c-EPI DWI. No significant differences were noted between the two image datasets for artifacts (p=0.876). The ratio of differences regarding hilar cholangiocarcinoma lesion sizes was significantly lower (p= 0.018) on T₂WI and DWI, as determined by the z-EPI DWI than that determined by the c-EPI method. The use of z-EPI DWI resulted in the accurate diagnosis of the Bismuth-Corlette classification of 15 tumors (15/16, 93.75%), whereas the use of c-EPI DWI resulted in correct diagnosis of 12 tumors (12/16, 75.00%). There were no significant differences between c-EPI DWI and z-EPI DWI in the ADC values of hilar cholangiocarcinoma lesions (p= 0.48).

Conclusion

z-EPI DWI resulted in remarkable image quality improvements for hilar cholangiocarcinoma. The ability to detect and delineate lesions using z-EPI DWI was superior to that of c-EPI DWI.

Total Bilirubin Level as a Predictor of Suboptimal Image Quality of the Hepatobiliary Phase of Gadoxetic Acid-Enhanced MRI in Patients with Extrahepatic Bile Duct Cancer

Objective

This study aimed to determine a factor for predicting suboptimal image quality of the hepatobiliary phase (HBP) of gadoxetic acid-enhanced MRI in patients with extrahepatic bile duct (EHD) cancer before MRI examination.

Materials and Methods

We retrospectively evaluated 259 patients (mean age ± standard deviation: 68.0 ± 8.3 years; 162 male and 97 female) with EHD cancer who underwent gadoxetic acid-enhanced MRI between 2011 and 2017. Patients were divided into a primary analysis set (n = 184) and a validation set (n = 75) based on the diagnosis date of January 2014. Two reviewers assigned the functional liver imaging score (FLIS) to reflect the HBP image quality. The FLIS consists of the sum of three HBP features, each scored on a 0–2 scale: liver parenchymal enhancement, biliary excretion, and signal intensity of the portal vein. Patients were classified into low-FLIS (0–3) or high-FLIS (4–6) groups. Multivariable analysis was performed to determine a predictor of low FLIS using serum biochemical and imaging parameters of cholestasis severity. The optimal cutoff value for predicting low FLIS was obtained using receiver operating characteristic analysis, and validation was performed.

Results

Of the 259 patients, 140 (54.0%) and 119 (46.0%) were classified into the low-FLIS and high-FLIS groups, respectively. In the primary analysis set, total bilirubin was an independent factor associated with low FLIS (adjusted odds ratio per 1-mg/dL increase, 1.62; 95% confidence interval [CI], 1.32–1.98). The optimal cutoff value of total bilirubin for predicting low FLIS was 2.1 mg/dL with a sensitivity of 95.1% (95% CI: 88.9–98.4) and a specificity of 89.0% (95% CI: 80.2–94.9). In the validation set, the total bilirubin cutoff showed a sensitivity of 92.1% (95% CI: 78.6–98.3) and a specificity of 83.8% (95% CI: 68.0–93.8).

Conclusion

Serum total bilirubin before acquisition of gadoxetic acid-enhanced MRI may help predict suboptimal HBP image quality in patients with EHD cancer.

Radiological assessment of secondary biliary tree lesions: an update

Objective

To conduct a systematic literature review of imaging techniques and findings in patients with peribiliary liver metastasis.

Methods

Several electronic datasets were searched from January 1990 to June 2017 to identify studies assessing the use of different imaging techniques for the detection and staging of peribiliary metastases.

Results

The search identified 44 studies, of which six met the inclusion criteria and were included in the systematic review. Multidetector computed tomography (MDCT) is the technique of choice in the preoperative setting and during the follow-up of patients with liver tumors. However, the diagnostic performance of MDCT for the assessment of biliary tree neoplasms was low compared with magnetic resonance imaging (MRI). Ultrasound (US), without and with contrast enhancement (CEUS), is commonly employed as a first-line tool for evaluating focal liver lesions; however, the sensitivity and specificity of US and CEUS for both the detection and characterization are related to operator expertise and patient suitability. MRI has thus become the gold standard technique because of its ability to provide morphologic and functional data. MRI showed the best diagnostic performance for the detection of peribiliary metastases.

Conclusions

MRI should be considered the gold standard technique for the radiological assessment of secondary biliary tree lesions.

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.

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.

Comparison of magnetic resonance imaging and 18-fludeoxyglucose positron emission tomography/computed tomography in the diagnostic accuracy of staging in patients with cholangiocarcinoma: A meta-analysis

BACKGROUND

Accurate clinical staging of patients with cholangiocarcinoma (CCA) has a significant impact on treatment decisions. In this study, we aimed to compare the diagnostic value of magnetic resonance imaging (MRI) and 18-fludeoxyglucose positron emission tomography/computed tomography (F-FDG PET/CT) for staging of CCA.

METHODS

We performed comprehensive systematic search in Web of Science (including MEDLINE) and Excerpta Medica Database for relevant diagnostic studies in accordance with the preferred reporting items for systematic reviews and meta-analysis statement. Based on data extracted from patient-based analysis, we calculated the pooled sensitivity and specificity with the 95% confidence intervals (CIs). In addition, the publication bias was assessed by Deek funnel plot of the asymmetry test. The potential heterogeneity was explored by threshold effect analysis and subgroup analyses.

RESULTS

Thirty-two studies with 1626 patients were included in present analysis. In T stage, the pooled sensitivity and specificity of MRI were 0.90 (95% CI 0.86-0.93), 0.84 (95% CI 0.73-0.91) respectively. The pooled sensitivity and specificity of F-FDG PET/CT were 0.91 (95% CI 0.83-0.95) and 0.85 (0.64-0.95) respectively. In N stage, the pooled sensitivity and specificity of MRI were 0.64 (95% CI 0.52-0.74) and 0.69 (95% CI 0.51-0.87) respectively. The pooled sensitivity and specificity of PET/CT were 0.52 (95% CI 0.37-0.66) and 0.92 (95% CI 0.79-0.97) respectively. In M stage, the pooled sensitivity and specificity of F-FDG PET/CT were 0.56 (95% CI, 0.42-0.69) and 0.95 (95% CI, 0.91-0.97) respectively. The Deek test revealed no significant publication bias. No threshold effect was identified. The subgroup analyses showed that pathological type (extrahepatic cholangiocarcinoma vs hilar cholangiocarcinoma/intrahepatic cholangiocarcinoma), country (Asia vs non-Asia) and type of MRI (1.5T vs. 3.0T) were potential causes for the heterogeneity of MRI studies and country (Asia vs non-Asia) was a potential source for F-FDG PET/CT studies.

CONCLUSION

The analysis suggested that both modalities provide reasonable diagnostic accuracy in T stage without significant differences between them. We recommend that both modalities be considered based on local availability and practice for the diagnosis of primary CCA tumors. In N stage, the diagnosis of lymph node metastasis (N) of CCA is still limited by MRI and F-FDG PET/CT, due to unsatisfactory diagnostic accuracy of both. Nevertheless, F-FDG PET/CT can be used to confirm lymph node metastasis while a negative result may not rule out metastasis. Furthermore, F-FDG PET/CT have a low sensitivity and a high specificity for detection of distant metastasis.

Comparison Between Multidetector CT and High-Field 3T MR Imaging in Diagnostic and Tumour Extension Evaluation of Patients with Cholangiocarcinoma

PURPOSE

To compare multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI) with cholangiopancreatography (MRCP) findings in the diagnostic evaluation of patients with cholangiocarcinoma (CCA) to establish tumour resectability.

METHODS

Thirty patients (22 M, 8 F) with pathologically proven CCA by post-surgical specimens (n = 20), core biopsy (n = 6) or cytology (n = 4) underwent both MDCT and MRI with MRCP. CCA lesions were classified on the basis of anatomical locations in intra-hepatic (iCCA), peri-hilar (pCCA) and distal (dCCA) tumours. Morphological tumour pattern, lesion size, biliary dilatation, tumour contrast enhancement type, lymph node involvement and vascular infiltration were directly compared between MDCT and MRI with MRCP. As a rule, a tumour resectability judgement for each patient was formulated by both imaging techniques comparing imaging results with direct surgical assessment (n = 20) or interventional procedures (n = 10).

RESULTS

In terms of anatomical location, 14 iCCA, 8 pCCA and 8 dCCA were observed; both imaging techniques were concordant about the identification and morphological characterization of tumour lesions and in the evaluation of tumour features (lesion size, contrast enhancement pattern, capsular retraction, biliary dilatation, lymph node involvement and vascular infiltration) as well as in assessing lesion resectability; an excellent agreement (k = 1) for the assessment of all the parameters included in imaging analysis was observed.

CONCLUSIONS

The comparative concordant results of our study suggest that MRI with MRCP represents a valid alternative to MDCT for the diagnostic evaluation of patients with CCA to establish tumour resectability providing multiplanar scanning of high-contrast imaging quality; MDCT should be preferred in uncooperative patients, in the presence of biliary stents or when MRI is absolutely contraindicated for incompatible medical devices.

[Role of magnetic resonance imaging in preoperative assessement of hilar cholangiocarcinoma]

Magnetic resonance cholangiopancreatography is a non-invasive imaging, highly performant in detecting and locating biliary stenosis and in predicting its malignancy. The combination of two and three-dimensional MRI sequences is recommended to assess a biliary obstacle. Cholangiopathies are the main differential diagnosis of cholangiocarcinomas. In addition to bile duct abnormalities beyond the stenosis, the predictive signs of malignancy are: asymmetric irregular luminal narrowing (longer than 3mm and thicker than 13mm), abrupt discontinuation of stenosis, and enhancement superior to that of the adjacent hepatic parenchyma during arterial and portal acquisitions. Diffusion sequences improve the sensitivity of biliary stenosis detection. Moreover, restriction of diffusion is useful for distinguishing malignant from benign stenosis. Combining Magnetic resonance cholangiopancreatography, late LAVA and diffusion sequences improves the sensitivity of detection of a possible biliary extension without significant specificity. MRI with gadolinium chelate injection is efficient in assessing vascular extension of cholangiocarcinomas. However its accuracy remains lower than that of Ct-scan. To assess hepatic, lymphatic and peritoneal extensions of cholangiocarcinomas, it is fundamental to combine diffusion and dynamic MRI sequences.

Cholangiocarcinoma and its mimickers in primary sclerosing cholangitis

Cholangiocarcinoma (CCA) is the most common malignancy in primary sclerosing cholangitis (PSC). Approximately half of CCA are diagnosed within two years of initial diagnosis and often have a poor prognosis because of advanced tumor stage at the time of diagnosis. Thus, rigorous initial imaging evaluation for detecting CCA is important. CCA in PSC usually manifests as intrahepatic mass-forming or perihilar periductal-infiltrating type. Imaging diagnosis is often challenging due to pre-existing biliary strictures and heterogeneous liver. Multimodality imaging approach and careful comparison with prior images are often helpful in detecting small CCA. Ultrasound is widely used as an initial test, but has a limited ability to detect small tumors in the heterogeneous liver with PSC. MRI combined with MRCP is excellent to demonstrate focal biliary abnormalities as well as subtle liver masses. Contrast-enhanced ultrasound is useful to demonstrate CCA by demonstrating rapid and marked washout. In addition, there are other disease entities that mimic CCA including hepatocellular carcinoma, confluent hepatic fibrosis, IgG4-related sclerosing cholangitis, inflammatory mass, and focal fat deposition. In this pictorial essay, imaging findings of CCA in PSC is described and discuss the challenges in imaging surveillance for CCA in the patients with PSC. Imaging findings of the mimickers of CCA in PSC and their differentiating features are also discussed.

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.

Peribiliary liver metastases MR findings

We described magnetic resonance (MR) features of peribiliary metastasis and of periductal infiltrative cholangiocarcinoma. We assessed 35 patients, with peribiliary lesions, using MR 4-point confidence scale. T1-weighted (T1-W), T2-weighted (T2-W) and diffusion-weighted images (DWI) signal intensity, enhancement pattern during arterial, portal, equilibrium and hepatobiliary phase were assessed. We identified 24 patients with periductal-infiltrating cholangiocellular carcinoma. The lesions in 34 patients appeared as a single tissue, while in a single patient, the lesions appeared as multiple individual lesions. According to the confidence scale, the median value was 4 for T2-W, 4 for DWI, 3.6 for T1-W in phase, 3.6 for T1-W out phase, 3 for MRI arterial phase, 3.2 for MRI portal phase, 3.2 for MRI equilibrium phase and 3.6 for MRI hepatobiliary phase. According to Bismuth classification, all lesions were type IV. In total, 19 (54.3%) lesions were periductal, 15 (42.9%) lesions were intraperiductal, and 1 (2.8%) lesion was periductal intrahepatic. All lesions showed hypointense signal in T1-W and in ADC maps and hyperintense signal in T2-W and DWI. All lesions showed a progressive contrast enhancement. There was no significant difference in signal intensity and contrast enhancement among all metastases and among all metastases with respect to CCCs, for all imaging acquisitions (p value >0.05). MRI is the method of choice for biliary tract tumors thanks to the possibility to obtain morphological and functional evaluations. T2-W and DW sequences have highest diagnostic performance. MRI does not allow a correct differential diagnosis among different histological types of metastasis and between metastases and CCC.

Phase II Study of Hepatic Arterial Infusion Chemotherapy with Oxaliplatin and 5-Fluorouracil for Advanced Perihilar Cholangiocarcinoma

Purpose To evaluate the efficacy and safety of hepatic arterial infusion (HAI) of oxaliplatin and 5-fluorouracil for advanced perihilar cholangiocarcinoma (PCC) in this prospective phase II study. Materials and Methods The protocol was approved by the local ethics committee, and all patients gave informed consent. Patients with nonresectable PCC were included in a prospective, open phase II study investigating HAI through interventionally implanted port catheters. HAI consisted of infusions of oxaliplatin 40 mg/m² for 2 hours, followed by 5-fluorouracil 800 mg/m² for 22 hours on days 1-3 every 3-4 weeks. A maximum of six cycles of HAI were applied for tumor control patients followed by maintenance with oral capecitabine until tumor progression. The primary end points were tumor response and progression-free survival (PFS). The secondary end points were local PFS, overall survival, and adverse events. Kaplan-Meier methodology and Cox regression analysis were used to evaluate the risk factors for survival. Results Between 2012 and 2015, 37 patients were enrolled. The overall response rate was 67.6% (25 of 37), and the disease control rate was 89.2% (33 of 37). Median PFS, local PFS, and overall survival were 12.2, 25.0, and 20.5 months, respectively. All three survival lengths in patients with periductal infiltrating pattern were found to be significantly longer than those in patients with mass-forming pattern (P < .001, hazard ratio < 0.2). Macroscopic growth patterns (P = .018) and number of HAI cycles (P < .001) were independent risk factors of survival. The most frequent adverse events were grades 1 and 2 gastrointestinal side effects and sensory neuropathy in 31 (83.8%) and 28 (75.7%) patients, respectively. Conclusion HAI with oxaliplatin and 5-fluorouracil may be an encouraging treatment choice for advanced PCC due to its high tumor control, survival benefit, and low toxicity, especially in patients with periductal infiltrating pattern. ^© RSNA, 2016.

Intrahepatic and hilar mass-forming cholangiocarcinoma: Qualitative and quantitative evaluation with diffusion-weighted MR imaging

OBJECTIVE

To qualitatively and quantitatively analyze the presentation of intrahepatic and hilar mass-forming cholangiocarcinoma with diffusion-weighted magnetic resonance imaging (DW-MRI).

MATERIALS AND METHODS

Twenty-eight patients with histopathologically proven mass-forming cholangiocarcinoma (hilar, n=17; intrahepatic, n=11) underwent hepatic DW-MRI at 1.5-T using free-breathing acquisition and three b-values (0,400,800s/mm(2)). Cholangiocarcinomas were evaluated qualitatively using visual analysis of DW-MR images and quantitatively with conventional ADC and normalized ADC measurements using liver and spleen as reference organs.

RESULTS

All cholangiocarcinomas (28/28; 100%) were visible on DW-MR images. DW-MRI yielded best conspicuity of cholangiocarcinomas than the other MRI sequences (P<0.001). Seven cholangiocarcinomas (7/11; 64%) showed hypointense central area on DW-MR images. Conventional ADC value of cholangiocarcinomas (1.042×10(-3)mm(2)/s±0.221×10(-3)mm(2)/s; range: 0.616×10(-3)mm(2)/s to 2.050×10(-3)mm(2)/s) was significantly lower than that of apparently normal hepatic parenchyma (1.362×10(-3)mm(2)/s±0.187×10(-3)mm(2)/s) (P<0.0001), although substantial overlap was found. No significant differences in ADC and normalized ADC values were found between intrahepatic and hilar cholangiocarcinomas. The use of normalized ADC using the liver as reference organ resulted in the most restricted distribution of ADC values of cholangiocarcinomas (variation coefficient=16.6%).

CONCLUSION

There is a trend towards a common appearance of intrahepatic and hilar mass-forming cholangiocarcinomas on DW-MRI but variations may be observed. Familiarity with these variations may improve the diagnosis of mass-forming cholangiocarcinoma.

Prognostication and response assessment in liver and pancreatic tumors: The new imaging

Diffusion-weighted imaging (DWI), dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and perfusion computed tomography (CT) are technical improvements of morphologic imaging that can evaluate functional properties of hepato-bilio-pancreatic tumors during conventional MRI or CT examinations. Nevertheless, the term “functional imaging” is commonly used to describe molecular imaging techniques, as positron emission tomography (PET) CT/MRI, which still represent the most widely used methods for the evaluation of functional properties of solid neoplasms; unlike PET or single photon emission computed tomography, functional imaging techniques applied to conventional MRI/CT examinations do not require the administration of radiolabeled drugs or specific equipments. Moreover, DWI and DCE-MRI can be performed during the same session, thus providing a comprehensive “one-step” morphological and functional evaluation of hepato-bilio-pancreatic tumors. Literature data reveal that functional imaging techniques could be proposed for the evaluation of these tumors before treatment, given that they may improve staging and predict prognosis or clinical outcome. Microscopic changes within neoplastic tissues induced by treatments can be detected and quantified with functional imaging, therefore these techniques could be used also for post-treatment assessment, even at an early stage. The aim of this editorial is to describe possible applications of new functional imaging techniques apart from molecular imaging to hepatic and pancreatic tumors through a review of up-to-date literature data, with a particular emphasis on pathological correlations, prognostic stratification and post-treatment monitoring.