Peripheral cholangiocarcinoma: comparison of MRI with CT

Multiparametric Magnetic Resonance Imaging Improves the Prognostic Outcomes in Patients With Intrahepatic Cholangiocarcinoma After Curative-Intent Resection

Purpose

The prognosis of patients with intrahepatic cholangiocarcinoma remains unclear. Thus, this study aimed at investigating whether additional multiparametric magnetic resonance imaging (mpMRI) would guide additional treatment and improve the prognostic outcomes of intrahepatic cholangiocarcinoma patients.

Methods and Materials

This retrospective study included 256 patients undergoing dynamic enhanced computed tomography scan only (CT group) and 31 patients undergoing both mpMRI and computed tomography scans (CT+MR group). Propensity score matching (PSM) was used to minimize the potential selection bias and confounding effects. The overall survival (OS) and recurrence-free survival (RFS) rates were compared between the two groups.

Results

More nodules (n = 6), additional biliary dilation (n = 4), and peritumoral parenchymal arterial phase hyperenhancement (n = 18) were found with the additional mpMRI scan, which led to treatment modification. Cox regression analysis revealed the survival advantage of additional mpMRI imaging based on the OS (HR 0.396, 95% CI 0.239–0.657, p < 0.001; PSM HR 0.400, 95% CI 0.218–0.736, p = 0.003) and RFS (HR 0.558, 95% CI 0.352–0.882, p = 0.013; PSM HR 0.508, 95% CI 0.288–0.897, p = 0.020).

Conclusions

Additional mpMRI helps clinicians to select better treatment options, lower the risk of tumor recurrence, and improve the overall survival.

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.

Update on the Diagnosis and Treatment of Cholangiocarcinoma

PURPOSE OF REVIEW

Cholangiocarcinoma is a rare biliary adenocarcinoma associated with poor outcomes. Cholangiocarcinoma is subdivided into extrahepatic and intrahepatic variants. Intrahepatic cholangiocarcinoma is then further differentiated into (1) peripheral mass-forming tumors and (2) central periductal infiltrating tumors. We aimed to review the currently known risk factors, diagnostic tools, and treatment options, as well as highlight the need for further clinical trials and research to improve overall survival rates.

RECENT FINDINGS

Cholangiocarcinoma has seen significant increase in incidence rates over the last several decades. Most patients do not carry the documented risk factors, which include infections and inflammatory conditions, but cholangiocarcinoma typically forms in the setting of cholestasis and chronic inflammation. Management strategies include multispecialty treatments, with consideration of surgical resection, systemic chemotherapy, and targeted radiation therapy. Surgically resectable disease is the only curable treatment option, which may involve liver transplantation in certain selected cases. Referrals to centers of excellence, along with enrollment in novel clinical trials are recommended for patients with unresectable or recurrent disease. This article provides an overview of cholangiocarcinoma and discusses the current diagnosis and treatment options. While incidence is increasing and more risk factors are being discovered, much more work remains to improve outcomes of this ominous disease.

MRI characteristics for the differential diagnosis of benign and malignant small solitary hypovascular hepatic nodules

PURPOSE

To compare the MRI findings of benign and malignant solitary hypovascular hepatic nodules and identify the differentiating features.

MATERIALS AND METHODS

A total of 135 patients with solitary hypovascular hepatic lesions up to 3 cm (mass forming intrahepatic cholangiocarcinoma, n=29; metastases, n=26; inflammatory pseudotumors and solitary necrotic nodule, n=48; and hemangioma, n=32) were assessed. MRI findings were analyzed, and lesions were scored for peripheral and intratumoral appearance and enhancement patterns.

RESULTS

Univariate and multivariate analyses showed that the most common findings for benign lesions were subcapsular, sharp margin, homogeneous, marked high signal on T2WI, mild hyperintensity on T2WI, increasing intensity of peripheral globular enhancement, and persistent central septum-like linear enhancement on delayed phase (P<0.05). An area under the curve of 0.955 was obtained for differentiating malignant from benign nodules using the combined imaging features of ill-defined margins, heterogeneity, decreasing intensity of peripheral rim-like enhancement, and central increasing intensity of patchy enhancement. Interobserver agreement was good, ranging from 0.72 to 1.00.

CONCLUSION

MRI may be a useful noninvasive method for determining whether hypovascular hepatic nodules are malignant or benign.

Intratumoral artery on contrast-enhanced computed tomography imaging: differentiating intrahepatic cholangiocarcinoma from poorly differentiated hepatocellular carcinoma

AIM

Differentiating intrahepatic cholangiocarcinoma (ICC) from poorly differentiated hepatocellular carcinoma (p-HCC) is often difficult, but it is important for providing appropriate treatments. The purpose of this study was to examine the features differentiating ICC from p-HCC on contrast-enhanced dynamic-computed tomography (CT).

METHODS

This study examined 42 patients with pathologically confirmed ICC (n = 19) or p-HCC (n = 23) for which contrast-enhanced dynamic CT data were available. CT images were analyzed for enhancement patterns during the arterial phase, washout pattern, delayed enhancement, satellite nodules, capsular retraction, lesion shape, and presence of an intratumoral hepatic artery, intratumoral hepatic vein, intratumoral portal vein, and bile duct dilation around the tumor, portal vein tumor thrombus, lobar atrophy, or lymphadenopathy.

RESULTS

Univariate analysis revealed the presence of rim enhancement (p = 0.037), lobulated shape (p = 0.004), intratumoral artery (p < 0.001), and bile duct dilation (p = 0.006) as parameters significantly favoring ICC, while a washout pattern significantly favored p-HCC (p < 0.001). Multivariate analysis revealed intratumoral artery as a significant, independent variable predictive of ICC (p = 0.037), and 15 ICCs (78.9%) showed this feature. Washout pattern was a significant, independent variable favoring p-HCC (p = 0.049), with 15 p-HCCs (65.2%) showing this feature.

CONCLUSION

The presence of an intratumoral artery in the arterial phase on contrast-enhanced dynamic CT was a predictable finding for ICC, and the presence of a washout pattern was a predictable finding for p-HCC, differentiating between ICC and p-HCC.

A review of the clinical diagnosis and therapy of cholangiocarcinoma

Cholangiocarcinoma (CCA) is the second most common primary hepatic malignancy worldwide. The incidence of intrahepatic CCA is increasing, whereas that of extrahepatic CCA is decreasing. This review looks at the new advances that have been made in the management of CCA, based on a PubMed and Science Citation Index search of results from randomized controlled trials, reviews, and cohort, prospective and retrospective studies. Aggressive interventional approaches and new histopathological techniques have been developed to make a histological diagnosis in patients with high risk factors or suspected CCA. Resectability of the tumour can now be assessed using multiple radiological imaging studies; the main prognostic factor after surgery is a histologically negative resection margin. Biliary drainage and/or portal vein embolization may be performed before extended radical resection, or liver transplantation may be undertaken in combination with neoadjuvant chemotherapy or chemoradiotherapy. Though many advances have been made in the management of CCA, the standard modality of treatment has not yet been established. This review focuses on the clinical options for different stages of CCA.

Differentiating combined hepatocellular and cholangiocarcinoma from mass-forming intrahepatic cholangiocarcinoma using gadoxetic acid-enhanced MRI

PURPOSE

To examine the differential features of combined hepatocellular and cholangiocarcinoma (HCC-CC) from mass-forming intrahepatic cholangiocarcinoma (ICC) on gadoxetic acid-enhanced MRI.

MATERIALS AND METHODS

Forty patients with pathologically proven combined HCC-CC (n = 20) and ICCs (n = 20) who had undergone gadoxetic acid-enhanced MRI were enrolled in this study. MR images were analyzed for the shape of lesions, hypo- or hyperintense areas on the T2-weighted image (T2WI), rim enhancement during early dynamic phases, and central enhancement with hypointense rim (target appearance) on the 10-min and 20-min hepatobiliary phase (HBP). The significance of these findings was determined by the χ(2) test.

RESULTS

Irregular shape and strong rim enhancement during early dynamic phases, and absence of target appearance on HBP favored combined HCC-CCs (P < 0.05). Lobulated shape, weak peripheral rim enhancement, and the presence of complete target appearance on the 10-min and 20-min HBP favored ICCs (P < 0.05). However, 10 CC-predominant type of combined HCC-CC showed complete or partial target appearance on 10-min HBP.

CONCLUSION

The shape of tumors, degree of rim enhancement during early dynamic phases, and target appearance on HBP were valuable for differentiating between combined HCC-CC and mass-forming ICC on gadoxetic acid-enhanced MRI.

Differentiating mass-forming intrahepatic cholangiocarcinoma from atypical hepatocellular carcinoma using gadoxetic acid-enhanced MRI

AIM

To examine the differential features of mass-forming intrahepatic cholangiocarcinoma (ICC) from atypical hypovascular hepatocellular carcinoma (HCC) on gadoxetic acid-enhanced magnetic resonance imaging (MRI).

MATERIALS AND METHODS

The institutional review board approved this retrospective study and waived informed patient consent. Seventy patients with pathologically proven ICCs (35) and hypovascular atypical HCCs (35) who had undergone preoperative gadoxetic acid-enhanced MRI were enrolled in this study. Images were analysed for the shape of the lesions and presence of hyperintensity on the T1-weighted image (T1WI) and hypo- or hyperintense areas on the T2-weighted image (T2WI). In addition, images were analysed for the presence of linear hyperintensity or multifocal, tiny, hyperintense foci on T2WI and the presence of rim enhancement during early dynamic phases and a central enhancement with a hypointense rim (target appearance) on the 10 and 20 min hepatobiliary phase images. The significance of these findings was determined by the X(2) test.

RESULTS

Univariate analysis revealed that the following significant parameters favour ICC or hypovascular HCC; the presence of T2 hypo- and hyperintense areas and target appearance on the 10 min hepatobiliary phase images favour ICC, and the presence of T2 linear hyperintensity and T2 multifocal hyperintense foci favour hypovascular HCC (p < 0.05). Multivariate analysis revealed that only target appearance on the 10 min hepatobiliary phase was predictive of ICC (p = 0.002) as 30 ICCs (85.7%) showed this feature. However, the target appearance was also observed in all six scirrhous HCCs.

CONCLUSION

A target appearance on the 10 min hepatobiliary phase images is the best predictor for identifying mass-forming ICC at gadoxetic acid-enhanced MRI.

Comparison of diffuse hepatocellular carcinoma and intrahepatic cholangiocarcinoma using sequentially acquired gadolinium-enhanced and Resovist-enhanced MRI

PURPOSE

The purpose of this study was to compare MRI findings of diffuse hepatocellular carcinoma (D-HCC) and intrahepatic cholangiocarcinoma (IHC) to identify characteristics of each.

MATERIALS AND METHODS

We retrospectively analyzed MRI that consisted of unenhanced T1- and T2-weighted image, gadolinium (Gd)-enhanced dynamic image, and sequentially acquired Resovist-enhanced image from 29 patients with D-HCCs and 32 patients with IHC.

RESULTS

On T2-weighted imaging, D-HCCs usually appeared as poorly defined, infiltrative mildly hyperintense masses, whereas IHC appeared as well-defined, lobulated mildly hyperintense masses with areas of strong hyperintensity and hypointensity. On dynamic- and Resovist-enhanced T1-weighted MRIs, D-HCCs appeared as hypovascular and homogeneously hypointense or isointense masses with internal reticulation, whereas IHD appeared as centripetal enhancing masses with or without delayed central hyperintensity. Biliary dilatation was predominantly observed in the area adjacent to the IHC and in the intratumoral area of D-HCC. Portal venous tumor thrombus was observed in most of the D-HCC, and portal vein encasement was seen in 17 of the IHC.

CONCLUSION

D-HCC and IHC exhibited characteristics of each at T1- and T2-weighted imaging, Gd-enhanced dynamic imaging, and sequentially acquired Resovist-enhanced T1-weighted imaging.

CT Differentiation of cholangiocarcinoma from periductal fibrosis in patients with hepatolithiasis

OBJECTIVE

The objective of our study was to determine useful CT findings for differentiating cholangiocarcinoma from periductal fibrosis in patients with hepatolithiasis.

MATERIALS AND METHODS

CT images of 30 patients with hepatolithiasis and pathologically proven cholangiocarcinoma (n = 14) or periductal fibrosis (n = 16) were retrospectively reviewed. Helical CT scans were obtained before, 30 seconds after, and 65 seconds after the start of contrast material injection. Analysis of CT findings included evaluation for the presence of periductal soft-tissue density, bile duct wall thickening at the stricture site, ascites, portal vein obliteration, lymph node enlargement, and a duct stone; assessment of the degree of ductal dilatation; and evaluation of the enhancement pattern of periductal lesions, thickened ductal wall, and hepatic parenchyma. The CT attenuation coefficients of the thickened ductal wall and adjacent normal-looking bile duct were measured on images obtained during each phase. Among these findings, statistically significant variables were determined using the Fisher's exact test and Student's t test. Sensitivity and specificity values of the CT criteria were also calculated.

RESULTS

The presence of periductal soft-tissue density (p = 0.002), higher enhancement of the duct than adjacent bile duct on portal venous phase images (p = 0.008), ductal wall thickening (p = 0.026), portal vein obliteration (p = 0.031), and lymph node enlargement (p = 0.031) were found to be the significant findings for differentiating cholangiocarcinoma from fibrosis in patients with hepatolithiasis. When any two or more of these five criteria were used in combination, we could identify 100% of the patients with cholangiocarcinoma but only 12.5% of the patients with fibrosis.

CONCLUSION

Cholangiocarcinoma in patients with hepatolithiasis can be diagnosed using specific CT criteria.

Intrabiliary MR Imaging: Assessment of Biliary Obstruction with Use of an Intraluminal MR Receiver Coil

PURPOSE

The primary aim of this study was to determine whether intrabiliary magnetic resonance (MR) imaging is feasible in a clinical setting and to optimize MR imaging parameters for the technique. In addition, it was attempted to determine the accuracy of intrabiliary MR imaging in the setting of biliary obstruction of unknown cause.

MATERIALS AND METHODS

Intrabiliary MR was performed prospectively in 15 patients with biliary obstruction of unknown cause. A 0.030-inch MR intravascular receiver coil was placed in an existing biliary tube. Intrabiliary MR was performed on a 1.5-T system. T1-weighted, T2-weighted, and single-shot fast spin-echo images were acquired. T1-weighted images were also acquired after the administration of a gadolinium contrast agent. Signal intensity analysis was conducted in the region of the common bile duct. Accuracy of intrabiliary MR, computed tomography (CT), MR, and cholangiography were determined by correlation with surgical pathologic findings.

RESULTS

Intrabiliary MR was successfully performed in 14 of 15 patients. MR examinations were performed in less than 1 hour. The signal-to-noise ratio in the region of the common bile duct with the intrabiliary MR technique was increased by a factor of 9 compared with standard surface-coil MR imaging (P < .00001). The mean n-plane resolution achieved was 740 +/- 20 microm x 1,150 +/- 20 microm obtained with use of a field of view of 18 cm x 18 cm (range, 15-24 cm) and a matrix of 256 x 160. Of the pulse sequences tested, the gadolinium-enhanced T1-weighted image was the best for identifying tumor and delineating tumor margins. Intrabiliary MR had a higher sensitivity than CT (100% vs 50%), a higher specificity than cholangiography (80% vs 20%), and a better correlation (P = .015) with surgical pathologic findings than CT, MR imaging, or cholangiography.

CONCLUSIONS

Intrabiliary MR was well tolerated in a clinical setting and provided high spatial resolution and excellent contrast between the biliary lumen and adjacent structures. Intrabiliary MR demonstrated an advantage in detecting the presence or absence of biliary malignancies compared with currently available standard imaging techniques. The technique may be useful to evaluate biliary obstruction of unknown cause.

Intrabiliary MR imaging

The goal of this research is to illustrate the potential role of interventional MR imaging ina clinical setting. As shown by this study, IBMR is feasible, is well tolerated, and positively affects patient management. IBMR allowed for significantly decreased field of view and high in-plane resolution and provided contrast between the biliary lumen and adjacent structures with high diagnostic accuracy. This technique enabled clinicians not only to improve imaging of the biliary tree but also to make a more accurate diagnosis. Based on this pilot work, there are several potential avenues of further expansion for IBMR. For example, enhanced imaging of the biliary tree may allow for monitoring of new biliary treatment regimens such as photodynamic therapy or molecular targeting. In addition, this technique may also foster development of innovative new percutaneous procedures that may eventually treat some biliary disorders under MR imaging guidance.

Benign nontraumatic inflammatory stricture of mid portion of common bile duct mimicking malignant tumor: Report of two cases

Benign nontraumatic inflammatory stricture of the common bile duct (CBD) may result in obstructive jaundice, which can be misdiagnosed as a malignant tumor of the CBD preoperatively. Two cases with strictures of the mid portion of the common bile duct presenting with obstructive jaundice are reported herein. Preoperative radiological studies prompted us to confidently make the diagnosis of cholangiocarcinoma. However, the postoperative diagnosis on histological examination of the resected lesions was chronic inflammation and fibrosis. The complications of chronic duodenal ulcer are considered as the etiology of these two disorders.

Biliary malignancies: multi-slice CT or MRI?

Cholangiocarcinoma is the most common malignant bile duct and the second most common primary malignant tumor in the liver. It can be classified as intrahepatic (peripheral) or extrahepatic. Extrahepatic cholangiocarcinoma originate most often from the main hepatic duct and confluence (referred to as Klatskin tumor). The patients usually present with jaundice because of biliary obstruction. Prognosis of hilar cholangiocarcinoma is poor, because most tumors are not resectable at the time of diagnosis. Surgical exploration should only be undertaken when there is potential for curative resection shown by imaging.

ERCP (endoscopic retrograde cholangio-pancreatography) demonstration of Klatskin tumors is often incomplete due to incomplete ductal filling. MR imaging and helical CT are the methods of choice in the diagnosis and staging of hilar cholangiocarcinoma. MR cholangiography, in conjunction with MR imaging and MRA, provides information on tumor size, bile duct involvement, and vascular compromise, and thus resectability of the tumor. Multi-phasic contrast-enhanced thin-section helical CT may show Klatskin tumors with a sensitivity of up to 100%. Tumors are better seen on arterial-dominant phase than on portal venous phase scans (sensitivity, 100% vs. 86%). However, single-slice CT is not accurate for assessing resectability (accuracy, 60%), because proximal tumor extent is largely underestimated. Preliminary experience with multi-slice CT indicates that the extent of bile duct involvement may be better displayed due to multi-planar imaging capabilities. Curved planar reconstruction of multi-slice CT data sets along the portal vein and the bile ducts reveals tumor involvement.

Intrahepatic cholangiocarcinoma have a non-specific imaging appearance. Because of abundant fibrous stroma, they exhibit little contrast enhancement during CT or MR imaging scanning in the early phase with delayed accumulation of contrast material. Although not pathognomonic, the presence of bile duct dilatation within the tumor and retraction of the liver capsule adjacent to the tumor are suggestive of the diagnosis.

In conclusion, the role of contrast-enhanced MR imaging with MR cholangiography and multi-slice CT in the detection and preoperative staging of cholangiocarcinoma is emphasised.

MR imaging of intrahepatic cholangiocarcinoma with pathologic correlation

OBJECTIVE

The objective of this study was to determine the MR imaging features of intrahepatic cholangiocarcinoma.

MATERIALS AND METHODS

MR images of 50 patients with pathologically proven intrahepatic cholangiocarcinoma were reviewed retrospectively. T1- and T2-weighted spin-echo images were obtained in all patients. Contrast-enhanced T1-weighted imaging was performed in 25 patients. Signal intensity and enhancement pattern of the tumors were correlated with pathology findings. The frequency of central hypointense regions on T2-weighted images and the intrahepatic bile duct dilatation of several other hepatic tumor types were investigated. Results were compared with imaging results of cholangiocarcinoma.

RESULTS

On T2-weighted images, central hypo- and hyperintense regions were detected in tumors in 27 and 17 patients, respectively. Contrast-enhanced T1-weighted imaging revealed central hypointense areas exhibiting homogeneous, heterogeneous, and no enhancement in six, three, and five, respectively, of 14 patients. Regions of fibrosis displayed enhancement, whereas those of coagulative necrosis showed no enhancement. The signal intensity difference on T2-weighted images between the center and the edge of the tumor correlated well with the fibrotic ratio difference between those two areas corresponding to the MR image (Spearman's rank correlation test, r = 0.72, 95% confidence interval = 0.48-0.86). T2-weighted images revealed central hypointense regions in 16 of 34 instances of hepatic colorectal metastases. However, hypointensity was observed in only 26 of 234 other hepatic tumors. Intrahepatic bile duct dilatation was evident in 27 of 50 cases of cholangiocarcinoma but occurred in only a single case of 34 instances of hepatic colorectal metastases.

CONCLUSION

The combination of the signal intensity on T2-weighted images and the enhancement pattern on contrast-enhanced T1-weighted images showed good correlation with the pathologic findings of cholangiocarcinoma. The occurrence of a central hypointense area on T2-weighted images is not pathognomonic; however, this finding, which reflects severe fibrosis, appears to be a characteristic marker of intrahepatic cholangiocarcinoma. The presence of intrahepatic bile duct dilatation may indicate cholangiocarcinoma, although it is difficult to differentiate cholangiocarcinoma from hepatic colorectal metastasis.

Incidence of benign lesions in patients resected for suspicious hilar obstruction

BACKGROUND

The differentiation between benign and malignant strictures at the hepatic hilum is difficult. The aim of this study was to assess the clinical and radiographical features of hilar lesions in a series of patients resected for a presumed cholangiocarcinoma.

METHODS

Of 132 consecutive patients undergoing resection for a suspicious lesion at the hepatic hilum, 20 (15 per cent) had a histopathologically proven benign tumour, diagnosed as chronic fibrosing or erosive inflammation, sclerosing cholangitis, or a granular cell tumour. All medical files and radiological examinations of the patients were reassessed.

RESULTS

Clinical symptoms were considered suspicious in 16 of 19 patients. At ultrasonography only one of 16 patients had an unsuspicious examination. In 14 of 18 patients cholangiographic images were considered suspicious. Overall reassessment confirmed a suspicious lesion in all 20 patients.

CONCLUSION

Because of the limitations of current diagnostic tools, a false-positive preoperative diagnosis of malignancy resulted in a 15 per cent resection rate of benign lesions in this series of suspicious hilar strictures.

[Proximal bile duct cholangiocarcinomas]

AIM

The aim of this retrospective study was to report a series of 12 patients with hilar cholangiocarcinoma treated by curative resection.

PATIENTS AND METHODS

Between 1980 and 1998, curative resection was performed in 12 patients out of 33 patients with a Klatskin's tumor. Preoperative biliary drainage was performed in 6 cases. Resection was limited to the extrahepatic bile duct in one case only. Resection was extended to the liver in 11 cases including segmentectomy I (n = 9), left hepatectomy (n = 7), right hepatectomy (n = 3) and segmentectomy IV (n = 1). Postoperative brachytherapy was performed in 3 patients combined with conventional radiotherapy. Conventional radiotherapy irradiation was performed in 2 patients and was associated with chemotherapy in 1 patient.

RESULTS

There was no postoperative mortality. Postoperative follow-up was uneventful in 5 patients. Actuarial survival rate at 1, 2, 3, and 5 years was 81, 57, 28 and 28%, respectively. Prolonged survivals (88 and 114 months) were observed.

CONCLUSION

Hilar cholangiocarcinomas have a poor prognosis. Curative resections are usually performed with major liver resections. RM cholangiography is now the most efficient examination for selection of surgical indications and choice of the best strategy. Long-term survival can be obtained with curative surgery. Adjuvant treatment has to be assessed by controlled trials.

Magnetic resonance imaging and diseases of the liver and biliary tract. Part 2. Magnetic resonance cholangiography and angiography and conclusions

Magnetic resonance cholangiography (MRC) relies on the strong T2 signal from stationary liquids, in this case bile, to generate images. No contrast agents are required, and the failure rate and risk of serious complications is lower than with endoscopic retrograde cholangiopancreatography (ERCP). Data from MRC can be summated to produce an image much like the cholangiogram obtained by using ERCP. In addition, MRC and conventional MRI can provide information about the biliary and other anatomy above and below a biliary obstruction. This provides information for therapeutic intervention that is probably most useful for hilar and intrahepatic biliary obstruction. Magnetic resonance cholangiography appears to be similar to ERCP with respect to sensitivity and specificity in detecting lesions causing biliary obstruction, and in the diagnosis of choledocholithiasis. It is also suited to the assessment of biliary anatomy (including the assessment of surgical bile-duct injuries) and intrahepatic biliary pathology. However, ERCP can be therapeutic as well as diagnostic, and MRC should be limited to situations where intervention is unlikely, where intrahepatic or hilar pathology is suspected, to delineate the biliary anatomy prior to other interventions, or after failed or inadequate ERCP. Magnetic resonance angiography (MRA) relies on the properties of flowing liquids to generate images. It is particularly suited to assessment of the hepatic vasculature and appears as good as conventional angiography. It has been shown to be useful in delineating vascular anatomy prior to liver transplantation or insertion of a transjugular intrahepatic portasystemic shunt. Magnetic resonance angiography may also be useful in predicting subsequent variceal haemorrhage in patients with oesophageal varices.

Incidence of primary cholangiocellular carcinoma of the liver in japanese patients with hepatitis C virus-related cirrhosis

BACKGROUND

Hepatitis C virus (HCV) infection is a major risk factor for the development of hepatocellular carcinoma. However, the risk factors for primary cholangiocellular carcinoma of the liver (PCC-L) have not been fully investigated. The authors determined the incidence of PCC-L in patients with HCV-related cirrhosis.

METHODS

Between 1980 and 1997, the authors prospectively studied 600 consecutive patients for the appearance of PCC-L; these patients were positive for HCV and later developed cirrhosis. The follow-up period ranged from 0 to 18.5 years (median, 7.2 years).

RESULTS

During the observation period, PCC-L developed in 14 patients (2.3%). Among these, 11 (1.8%) had cholangiocellular carcinomas and the other 3 (0.5%) had a combined type of hepatocellular and cholangiocellular carcinoma. Within the same period, hepatocellular carcinoma (HCC) developed in 206 patients (34.3%). The cumulative rates of newly diagnosed PCC-L were 1.6% at 5 years and 3.5% at 10 years, which was about 1000 times higher than the estimated incidence of PCC-L in the general population of Japan. PCC-L was treated by surgical resection in 3 patients who survived for > 3 years. However, the other 11 patients received palliative therapy or chemotherapy. The survival rates among PCC-L patients were 39.3%, 23. 6%, and 16.5% at the end of 1, 3, and 5 years, respectively, and were significantly lower than those of HCC (P = 0.0001).

CONCLUSIONS

The results of this study show a relatively high incidence of PCC-L in patients with HCV-related cirrhosis, and also show that this type of liver cancer is associated with a relatively poor prognosis. These results indicate that HCV-related cirrhosis is a major risk factor for PCC-L in Japanese patients.

Intrahepatic peripheral cholangiocarcinoma: comparison of dynamic CT and dynamic MRI

PURPOSE

The purpose of this work was to compare dynamic MRI (D-MRI) with dynamic CT (D-CT) for the diagnosis of peripheral cholangiocarcinoma (PCC) of the liver.

METHOD

Twenty patients with PCC underwent both D-CT and D-MRI during the early, middle, and delayed phase after contrast medium administration. The findings from D-MRI were compared with those from D-CT.

RESULTS

D-CT and D-MRI exhibited a similar tumoral enhancement pattern, and this enhancement was more conspicuous on D-MRI. A wedge-like enhancement area peripheral to the tumor was observed in 9 (45%) patients on D-CT and 11 (55%) patients on D-MRI. Ductal dilatation was found in 13 (65%) patients on both techniques. Vascular involvement and extrahepatic invasion were seen in nine (45%) and two (10%) patients, respectively. The relationship of the tumor to the vessels and surrounding organs was more easily evaluated on D-CT.

CONCLUSION

Both D-CT and D-MRI can provide important information for the diagnosis of PCC. D-CT is better than D-MRI for demonstrating vascular involvement and extrahepatic invasion. D-MRI gives more conspicuous enhancement.

Cholangiocarcinoma: spectrum of appearances on MR images using current techniques

This study describes the spectrum of appearances of cholangiocarcinoma on magnetic resonance (MR) sequences, including gadolinium-enhanced, fat-suppressed spoiled gradient echo images and MR cholangiography. Fifteen patients were included in the study. Histologic diagnosis was established in 11 patients by surgical resection (6 patients), percutaneous biopsy (4 patients), and open liver biopsy (1 patient). The final diagnosis was determined by correlation of the MR findings with cholangiographic studies and laboratory studies in 4 patients. MR studies were performed at 1.5 T, and the following sequences were obtained: T1-weighted spoiled gradient echo (SGE), T1-weighted fat-suppressed spin echo or SGE, T2-weighted fat-suppressed conventional or turbo spin echo, MR cholangiography, and gadolinium-enhanced T1-weighted fat-suppressed SGE images. The following determinations were made: tumor location, tumor extent, ductal dilatation, ductal wall thickness, signal intensity, enhancement pattern, and associated findings. Mass-like neoplasms were peripheral (6 patients), hilar (1 patient), and extrahepatic (2 patients). Circumferential tumors were hilar (2 patients) and extrahepatic (4 patients). All peripheral tumors were multifocal. Mass-like tumors were well-defined, rounded, and ranged from 1 to 14 cm in diameter. Circumferential tumors had less well-defined margins and measured from 3 to 15 mm in thickness. All mass-like tumors were moderately hypointense on T1-weighted images and mildly to moderately hyperintense on T2-weighted images. The circumferential tumors were iso- to moderately hypointense on T1-weighted images and iso- to mildly hyperintense on T2-weighted images. Mass-like tumors were generally well shown on non-contrast and immediate gadolinium-enhanced images, whereas circumferential tumors were poorly seen on non-contrast images and best shown on gadolinium-enhanced T1-weighted fat-suppressed images. The degree of enhancement ranged from minimal to intense on immediate gadolinium-enhanced images, with all tumors becoming more homogeneous in signal intensity on images obtained between 1 and 5 min following contrast administration. Tumor-containing lymph nodes greater than or equal to 1 cm in diameter were demonstrated in 11 out of 15 patients (73.3%). These were best shown on T2-weighted fat-suppressed images and gadolinium-enhanced fat-suppressed SGE images. MR cholangiography demonstrated the level of obstruction and degree of dilatation of the proximal biliary system in 5 out of 6 patients who underwent MR cholangiography. The spectrum of appearances of cholangiocarcinoma is demonstrable on MR images. Mass-like tumors are well shown on both pre- and post-gadolinium sequences. Circumferential tumors may cause minimally increased duct wall thickness and are most clearly shown on gadolinium-enhanced fat-suppressed SGE images obtained 1 to 5 min following gadolinium administration.

Primary hepatic malignant neoplasms

Although metastatic disease is by far the most common form of neoplastic involvement of the liver, a variety of primary hepatic malignant neoplasms may develop from any of the cell types within the liver. Primary hepatic neoplasms include hepatocellular carcinoma, intrahepatic cholangiocarcinoma, biliary cystadenocarcinoma, and a variety of mesenchymal tumors. This article reviews the clinical presentation and pathology of these tumors and discusses their sonographic, CT scan, and MR imaging appearance.

MRI of clonorchiasis and cholangiocarcinoma

Intrahepatic cholangiocarcinomas are usually categorized as peripheral cholangiocarcinoma or hilar cholangiocarcinoma on the basis of the site of origin. Clonorchiasis is a trematodiasis caused by chronic infestation of liver flukes, which are largely confined to the Orient, from Japan to Vietnam. The close relationship between clonorchiasis and cholangiocarcinoma has long been emphasized. This paper discusses the efficacy and possible roles of MRI for imaging clonorchiasis and cholangiocarcinoma of the liver. Although sonography, CT, and direct cholangiography have been used traditionally to diagnose these diseases, the role of MRI has been increasing rapidly with dramatic progress of the MRI techniques. We review MRI findings of clonorchiasis and cholangiocarcinoma and discuss the potential usefulness of MRI.

Intrahepatic cholangiocarcinoma: MRI and pathologic correlation in 14 patients

PURPOSE

Our goal was to determine the MR features of intrahepatic cholangiocarcinoma and to correlate them with pathologic findings in a surgical series.

METHOD

MRI in 14 patients with intrahepatic cholangiocarcinoma who had undergone resection was reviewed. All patients had T1- and T2-weighted SE sequences. Contrast-material-enhanced MRI was performed in 12 cases. Comparison between findings at MRI and pathologic examination was made.

RESULTS

MRI depicted all the lesions but one satellite nodule of 2 cm diameter. All lesions were hypointense relative to the liver on T1-weighted images. On T2-weighted images, the tumors were predominantly isointense or slightly hyperintense relative to liver parenchyma in nine cases (64%) and were strongly hyperintense in five cases (36%). Central hypointense areas or bands were seen in eight cases. No capsule was detected. On contrast-enhanced MR studies, all lesions had progressive and concentric filling with contrast material. Associated findings such as vascular encasement, focal liver atrophy, or dilatation of intrahepatic bile ducts were observed in 10 cases (71%). Comparison with pathologic examination revealed that lesion signal intensity on T2-weighted MR images was due mostly to the amount of fibrosis, necrosis, and mucous secretion within the lesion. The nine isointense or slightly hyperintense lesions contained abundant fibrosis and had a low content of mucous secretion or necrosis, whereas the five hyperintense lesions contained low or moderate fibrosis and prominent mucous secretion and/or necrosis.

CONCLUSION

Our study suggests that the MR features of intrahepatic cholangiocarcinoma are well correlated with pathologic findings, but are nonspecific. Associated findings may strengthen the diagnosis of intrahepatic cholangiocarcinoma at MRI.