Mucin-Producing Carcinoma of the Gallbladder: Evaluation by Magnetic Resonance Cholangiopancreatography in Three Cases

We report three cases of mucin-producing carcinoma of the gallbladder, along with the magnetic resonance (MR) findings, especially the findings on a MR cholangiopancreatography. In our cases, linear or curvilinear streaks were detected running along the long axis of an enlarged gallbladder (mucus thread sign). When such findings were seen, a mucin-producing carcinoma of the gallbladder should be included as a differential diagnosis. Thus, gadolinium-enhanced MR imaging is mandatory for the precise diagnosis of the mucin-producing carcinoma of the gallbladder.

Bile Duct Hamartomas: US, CT and MR Findings in Eight Patients, Focusing on the US Findings

PURPOSE: To describe the US, CT and MR findings in eight patients with bile duct hamartomas. MATERIALS AND METHODS: Bile duct hamartomas were diagnosed in eight patients (5 men and 3 women; age range, 41-69 years; mean age, 56 years) by liver biopsy. The US, CT and MR findings were retrospectively reviewed. RESULTS: Ultrasonographically, the bile duct hamartomas presented diffuse inhomogeneous and coarse echo texture with focal lesions, including bright spotty echoes or small hyperechoic nodules (n=7), hypoechoic nodules (n=7) and comet-tail echo (n=3) in seven patients. 16 of the 39 definable hypoechoic nodules that ranged in size from 5 mm to 16mm showed posterior enhancement. CT revealed innumerable hypodense nodules measuring 2-5 mm (n=3), 2-13 mm (n=1), 2-15 mm (n=2) and 2-18 mm (n=1) in seven patients. They were usually irregular in shape and showed no enhancement, but became more apparent after the administration of intravenous contrast medium. The innumerable hypodense nodules on enhanced CT scans were uniformly (n=5) or nonuniformly (n=2) distributed throughout the liver. In four patients, MR images showed multiple small cyst-like lesions 2-13 mm in diameter. These small cystlike lesions were much more apparent on T2-weighted images or MR cholangiography. The diagnosis was made by either core-needle or wedge biopsy. In one patient, a small single lesion on the liver surface was not visible on the imaging studies. Pathologic examination revealed multiple bile duct hamartomas of varying size or microhamartomas. CONCLUSION: Although the bile duct hamartomas on CT and MR presented as numerous intrahepatic, small cyst-like lesions, they on US showed variable findings consisting of inhomogeneous and coarse echo texture with focal lesions, including bright spotty echoes or small hyperechoic nodules, hypoechoic nodules, and comet-tail echoes.

Radiological Spectrum of Intraductal Papillary Tumors of the Bile Ducts

Papillary tumor of the bile duct is characterized by the presence of an intraductal tumor with a papillary surface comprising innumerable frondlike infoldings of proliferated columnar epithelial cells surrounding slender fibrovascular stalks. There may be multiple tumors along the bile ducts (papillomatosis or papillary carcinomatosis), which are dilated due to obstruction by a tumor per se, by sloughed tumor debris, or by excessive mucin. Radiologically, the biliary tree is diffusely dilated, either in a lobar or segmental fashion, or aneurysmally, depending on the location of the tumor, the debris, and the amount of mucin production. A tumor can be depicted by imaging as an intraductal mass with a thickened and irregular bile duct wall. Sloughed tumor debris and mucin plugs should be differentiated from bile duct stones. Cystically or aneurysmally, dilated bile ducts in mucin-hypersecreting variants (intraductal papillary mucinous tumors) should be differentiated from cystadenoma, cystadenocarcinoma and liver abscess.

Intraluminal Brachytherapy after Metallic Stent Placement in Primary Bile Duct Carcinoma

PURPOSE: To determine the effect of intraluminal brachytherapy on stent patency and survival after metallic stent placement in patients with primary bile duct carcinoma. MATERIALS AND METHODS: Twenty-seven patients with primary bile duct carcinoma underwent metallic stent placement; in 16 of the 27 intraluminal brachytherapy with an iridium-192 source (dose, 25 Gy) was the performed. Obstruction was due to either hilar (n=14) or non-hilar involvement (n=13). For statistical comparison of patients who underwent/did not undergo intraluminal brachytherapy, stent patency and survival were calculated using the Kaplan-Meier method and an independent t test. RESULTS: The mean durations of stent patency and survival were 9.1 and 10.0 months respectively in patients who underwent intraluminal brachytherapy, and 4.2 and 5.0 months in those who did not undergo this procedure (p<0.05). The mean durations of stent patency and survival among the 22 patients who died were 7.6 (range, 0.8 -16.1) and 8.3 (range, 0.8-17.3) months, respectively, in the eleven patients who underwent intraluminal brachytherapy, and 4.2 (range, 0.9-8.0) and 5.0 (range, 0.9-8.4) months in those whom the procedure was not performed (p<0.05). CONCLUSION: Intraluminal brachytherapy after stent placement extended both stent patency and survival in patients with primary bile duct carcinoma.

Peripheral Cholangiocarcinoma: Radiologic Significance of Hypoechoic Halo Sign on Sonography

PURPOSE: To determine the prevalence and characteristics of the hypoechoic halo sign in peripheral cholangiocarcinoma. MATERIALS AND METHODS: Seventeen sonograms of 17 patients with peripheral cholangiocarcinoma histologically proven by either percutaneous needle biopsy (n=16) or surgical biopsy (n=1) were retrospectively reviewed. The size, margin, homogeneity and internal echogenicity of the masses as well as their peritumoral ductal dilatation and intratumoral calcification were ascertained, and the presence of a hypoechoic halo, and if present, its thickness and type, were also determined. We arbitrarily defined a 'thin' and 'thick' halo respectively, as one with a thickness less than of less than 3 mm, and 3 mm or more, and classified halos as 'intratumoral', 'extratumoral', or 'mixed'. RESULTS: Tumor diameter ranged from 4 to 13.5 (mean, 7.3) cm, and the margin was well-defined in 15 cases (smooth: n=2; lobulated: n=13) and irregular in two. Echogenicity was slightly heterogeneous in 11 cases, severely heterogeneous in three, and homogeneous in three, while the central portion was hyperechoic in eight cases, isoechoic in seven, and hypoechoic in only two. A hypoechoic halo was detected in 10 of 15 tumors(67%) with isoechoic centers. In evaluating the halo, two cases in which the mass was hypoechoic were excluded. All ten hypoechoic halos were at least 3 (range, 4-13; mean, 8.3) mm thick; in two cases the presence of a halo was equivocal, and in three there was no halo. Eight of ten halos were the mixed type, two were intratumoral, and none were extratumoral. Peritumoral ductal dilatation was seen in four cases (24%), but no internal calcification was observed. CONCLUSION: US showed that the margins of peripheral cholangiocarcinomas were mostly well-defined and smooth (12%) or lobulated (76%), and that masses were mainly heterogeneous (64%). A hypoechoic halo, which in all cases was thick and in 80% of cases was mixed, was noted in 67% of tumors with a hyper (47%) or isoechoic (41%) center. A halo of this kind may be useful in isoechoic mass detection and also in the differentiation of hyperechoic peripheral cholangiocarcinoma from hepatic hemangioma, the most common hyperechoic benign tumor.

Management of Advanced Hilar Biliary Malignancy with X-shaped Stenting Technique

PURPOSE: To report X-shaped stent insertion and its result in the patients with advanced hilar malignancy. MATERIALS AND METHODS:X-shaped stents were inserted in six patients with advanced hilar malignancy involving segmental branches of both intrahepatic bile ducts (IHD). The causes were cholangiocarcinomas in five patients and recurrent GB cancer in one. The procedure includes three steps: 1) the insertion of two wires through three IHDs in an X configuration, using a stone basket; 2) balloon dilatation of lesions, and 3) the in-sertion of two stents in an as X configuration. Stents were inserted after balloon dilatation in five patients, and without balloon dilatation in one. Changes in serum bilirubin levels and procedure-related problems were reviewed. RESULTS: In all patients, serum bilirubin levels gradually decreased, but in two, they increased again. One of these two died of sepsis after 1 month. There was bile leakage through the puncture and bile was extracted from malignant ascites. In the other patient, occlusion of the left stent tip occurred, and additional left PTBD was performed 3 months later. Hemobilia developed in all five patients with balloon dilatation, these all experianced pain during dilatation , but afterwards this disappeared. One stent without pre-balloon dilation showed incomplete self-expansion at the crossing part and supplementary balloon dilatations were performed. CONCLUSION: In patients with advanced hilar malignancy, X-shaped stent insertion is a new palliation. Problems such as hemobilia, pain, and intraperitoneal bile leakage may, however, occur.

Hepatocellular Carcinoma with Bile Duct Involvement: Computed Tomographic (CT) Findings

PURPOSE: To describe the radiologic features of computed tomography(CT) in hepatocelluar carcinoma(HCC) with bile duct involvement. MATERIALS AND METHODS: We retrospectively analyzed the two phase spiral CT findings of 31 patients in whom HCC with bile duct invasion (n=28) or compression (n=3), was diagnosed. Eight of these underwent follow-up CT after transarterial chemoembolization. We analyzed the size, type, location, enhancement pattern, and lipiodol retention of parenchymal and intraductal masses, as well as their and lymphadenopathy. RESULTS: In all patients with bile duct invasion, single or multiple masses were demonstrated in the bile ducts. Intraductal masses showed the same enhancement characteristics as the parenchymal mass (kappa 0.550, p < .001), and were contiguous to this mass. In 14 of 28 patients, intraductal masses filled the peripheral intrahepatic bile ducts and extended to the common bile ducts. In the other 14, the parenchymal mass extended to the area of the porta hepatis and then directly invaded the large ducts. In nine of the 28 patients, there was a hypoattenuated cleft between the intraductal mass and ductal wall. In six, a parenchymal mass was not apparent (n = 2), or was smaller than 2cm (n = 4). In five of eight patients (62.5%), follow-up CT after transarterial chemoembolization showed compact or partial lipiodol retention within the intraductal mass. In patients with bile duct compression, perihilar lymph nodes were noted along with the dilated intrahepatic duct but no intraductal mass was demonstrated in the duct. CONCLUSION: Hepatocellular carcinomas cause bile duct dilatation either by direct invasion or by extrinsic compression of the bile duct with surrounding enlarged nodes. For the diagnosis of this condition, CT is helpful.

Intrahepatic Cholangiocarcinoma: Gross Appearance and Corresponding Pathologic and Radiologic Features

PURPOSE: To assess the clinical and pathologic features of each type of intrahepatic cholangiocarcinoma,which is divided into three types according to gross appearance, and to determine the efficacy of CT in detectingthis tumor. MATERIALS AND METHODS: The pathologic and CT features of 53 surgically proven cases of intrahepaticcholangio-carcinoma were reviewed. On the basis of their gross appearance, the tumors were divided into threetypes, as follows: mass forming (n=33), periductal infiltrating (n=6), and intraductal growth type (n=14). CTscans were analyzed for sensitivity of detection and correlation between a tumors appearance and itshistopathology. RESULTS: The most common histopathologic feature of mass forming and periductal infiltrating typewas tubu-lar adenocarcinoma, while in the intraductal growth type, papillary adenocarcinoma (100%) was common.With regard to pattern of tumor spread, intrahepatic and lymph node metastasis were more common in the massforming and periductal infiltrating type than in the intraductal growth type. CT findings including intra-hepaticmass, ductal wall thickening or intraductal mass associated with segmental dilatation of intrahepataic bile ducts,corresponded with these morphologic types. CONCLUSION: This classification according to gross appearance is ofconsiderable value when interpreting the pathologic features of intrahepatic cholangiocarcinoma. CT seems to be auseful modality for the detection of tumors and may be consistent with their gross morphologic findings.

CT Findings of Intrahepatic Cholangiocarcinoma Associated with Hepatolithiasis

PURPOSE: To assess the CT findings of intrahepatic cholangiocarcinoma associated with hepatolithiasis. MATERIALS AND METHODS: The CT features of 26 patients with cholangiocarcinoma and hepatolithiasis were reviewed and compared with those of 23 patients with intrahepatic stones alone, acting as control subjects. CT findings were analyzed for tumor appearance and adjacency to hepatolithiasis. We studied clinical findings, noting the presence or absence of wall thickening or soft tissue attenuation within the bile duct, the luminal diameter of dilated bile duct, and the presence of periductal enhancement, and compared these with the findings for control groups. RESULTS: CT images of the tumor revealed a hepatic low-attenuating mass with peripheral rim enhancement(n=14, 54 %), or periductal thickening, or low-attenuating lesions in segmental dilatation of intrahepataic bile ducts(n=12, 46%). Most hepatic tumors were seen in areas adjacent to hepatolithiasis, or in a bile duct. Compared with control groups, patients with cholangiocarcinoma were old (p0.05). CONCLUSION: When an intrahepatic low-attenuating mass, or peridutal thickening and low-attenuating lesions in segmental dilated intrahepatic duct are found associated in adjacent intrahepatic stones, intrahepatic cholangiocarcinoma should be considered.

Prominent Papilla of Vater at CT: Differentiation between Benign and Malignant Lesion

PURPOSE: To establish the criteria for differential diagnosis between malignant tumor and benign prominenceof papilla of Vater, as seen on CT. METHOD AND MATERIALS: Sixteen consecutive patients with prominent papilla ofVater, as seen on CT during a ten-month period were includedin this study. Final diagnosis was papilla of Vatercancer (n=5), chronic inflammation (n =3), benign tumor (n=3), or and normal (n=5), and this was confirmed bysurgery in 11 cases, and endoscopy in five. Papilla size and attenuation, the presence of accompanied dilatationof the bile or pancreatic duct, and lymph node enlargement were analyzed by two experienced radiologists, whoreached a conensus. A past history of stone disease, laboratory findings such as serum bilirubin, serum alkalinephosphatase, or endoscopic findings of duodenal diverticulum were additionally analyzed. RESULT: Papilla size wasthe only significantly different CT finding between malignant and benign lesions, and serum alkaline phosphataselevels were also significantly different between the two groups. The smallest malignant tumor was 18 mm and thelargest benign lesion was 15 mm. The presence of bile or pancreatic duct dilatation, serum bilirubin level,attenuation of the mass, a history of stone disease, and lymph node enlargement were not significantly differentbetween the two groups. CONCLUSION: In patients with prominent papilla of Vater, as seen on CT, a mass largerthan 18 mm is the only reliable radiologic finding to indicate malignant tumor of papilla of Vater. Serum alkalinephosphatase levels can, in addition, be helpful for the differential diagnosis of benign and malignant lesions.

Hepatocellular Carcinoma Localized in the Bile Duct Lumen: Two case report

Intrabile duct tumor growth of hepatocellular carcinoma is an uncommon manifestation, but intraluminal bileduct hepatocellular carcinoma without primary hepatic parenchymal lesions is extremely rare. To our knowledge,only a few case reports have been published. We encountered two cases of primary hepatocellular carcinoma arisingin the bile duct; serum alpha-fetoprotein levels were within the normal limits. Both showed the followingcharacteristic radiologic features: 1) Cholangiography revealed filling defects within the dilated bile duct; 2)two-phase abdominal CT showed enhancement during the arterial-dominant phase and washout during the tissueequilibrium phase, as in typical HCC; and 3) hepatic arteriography revealed hypervascular tumor staining. Surgerywas performed and the resected specimen showed no detectable primary hepatic parenchymal mass; on the basis of thepathologic findings, intraluminal bile duct hepatocellular carcinoma was confirmed. We cautiously assume that thispeculiar type of HCC may arise primarily from bile duct mucosa.

US-guided Left-sided Percutaneous Biliary Drainage: Analysis of the Technical Factors Related to Procedure

PURPOSE: To evaluate the factors affecting procedure related technical difficulties of US-guided left sidedPTBD and the complications involved in the use of this method. MATERIAL AND METHODS: We prospectively evaluatedUS-guided left PTBD in 26 patients with malignant biliary obstructions. The causes of underlying malignancy werebile duct carcinoma(n=10), adenocarcinoma of the pancreas(n=8), GB carcinoma(n=4), metastasis to the portahepatis(n=2), duodenal carcinoma(n=1), hepatocellular carcinoma(n=1). We divided the procedure into four steps forthe evaluation of technical difficulties, and we measured procedure time and fluoroscopic exposure time. And weevaluated the incidence of procedure related complications. RESULTS: US-guided left PTBD was successful in allattempted cases. The average procedure time and fluoroscopic exposure time involved were 14.2 min. and 5.5 min.,respectively. From the first step to the fourth step, the average time required was 4.4 min, 2.3 min., 1.9 min.,5.6 min., respectively. One major complication involved sepsis(3.8%), and ten minor complications including fivetransient hemobilia(19.2%), three tube malfunction(11.5%), and two fever(7.6%). CONCLUSION: US-guided left PTBDwas easy to perform and a relatively safe method. The total procedure time was short, and as the radiologistbecomes more experienced, this could be further reduced.

Thin Section Helical CT Findings of Klatskin Tumor and Benign Stricture: Cholangiographic Correlation

PURPOSE: The purpose of this study was 1) to describe the thin section helical CT findings of hilar cholangiocarcinoma and of benign stricture, and to discuss the differential points between the two disease entities and 2) using cholangiographic correlation, to evaluate the diagnostic accuracy of helical CT in determining the extent of hilar cholangiocarcinoma. MATERIALS AND METHODS: Twenty-seven patients with hilar cholangiocarcinoma and eight with benign biliary dilatation were studied. All except four with hilar cholangiocarcinoma, who underwent CT using a conventional scanner, were studied with two-phase helical CT. In all patients, cholangiographs were obtained by digital fluoroscopy after the injection of contrast materials into PTBD catheters. The level of obstruction was classified according to Bismuth, and 35 CT scans were studied blindly and retrospectively by two radiologists. The findings were analyzed for the presence of tumor, and then divided into two groups (cholangiocarcinomas and benign strictures), and the positive predictive value was calculated. The CT images of klatskin tumor were analyzed with special emphasis on the level and shape of the hilar obstruction. The level of biliary obstruction and extent of the tumor were carefully correlated with the results of cholangiography. RESULTS: Thin-section spiral CT correctly identified all tumor mass as a focal wall thickening obliterating the lumen. On arterial/portal phase CT scanning, 81% of infilterative tumors showed high attenuation. In all patients, differentiation between benign stricture and klatskin tumor was possible ; correct identification of the level of obstruction and extent of tumor, according to Bismuth's classification, was possible in 63% of cases. CONCLUSION: For correct diagnosis of hilar cholangiocarcinoma and differentiation of benign stricture, helical CT was highly accurate and effective. Because of limital Z-axis resolution, however, the exact intraductalextent of the tumor was less accorately diagnosed.