[CT appearance of thorotrast-related and non-thorotrast-related peripheral cholangiocarcinoma]

To assess the differences in CT findings among patients with peripheral cholangiocarcinoma with and without a history of Thorotrast administration, CT studies from 13 Thorotrast patients and eight non-Thorotrast patients were reviewed. Diagnostic and prognostic differences were evaluated between the two groups. Despite periodic imaging surveillance, eight of the 13 (62%) lesions discovered by CT were larger than 6 cm. The prognosis for Thorotrast patients was unfavourable due to difficulties in early detection and complications from associated hepatic fibrosis. The main problem with early detection was that a background of uneven Thorotrast deposits visualized in the liver disguised the tumor as Thorotrast granulations. Although non-Thorotrast patients were not monitored regularly, they had a better chance of undergoing curative resection for the following three reasons: 1) it was easy to detect the tumor (detection rate, 100%); 2) this group rarely had associated liver cirrhosis in noncancerous areas, and 3) non-Thorotrast patients were younger than Thorotrast patients. Early detection of cancer by CA19-9 assay and imaging in asymptomatic subjects without any history of liver disease could be important steps toward the early and radical resection of cancer to achieve a better prognosis.

[Value of ultrasound in follow-up of biliary metal stents--initial results]

Self-expandable metallic biliary endoprostheses (= "stents") are an accepted therapeutic alternative in the palliative treatment of malignant biliary obstruction. The physiological direction of bile flow is re-established for a varying period of time. Sonography is an acutely available modality for the evaluation of symptomatic patients who are carriers of such endoprostheses. The cause of recurrent obstructive jaundice can be diagnosed quickly and a new intervention can be planned carefully.

Anterior segmentectomy with caudate lobectomy for hilar cholangiocarcinoma

When hepatic resection for hilar chol-angiocarcinoma with impaired hepatic function is performed, minimal resection of the involved segment on the basis of the extent of cancer invasion must be selected so as to minimize the risk of postoperative hepatic failure. We describe our experience with anterior segmentectomy with caudate lobectomy for hilar cholangiocarcinoma in two patients with impaired hepatic function and poor general health. These procedures were curative resections histologically, and were not followed by severe postoperative complications. Anterior segmentectomy together with caudate lobectomy was considered appropriate treatment for hilar cholangiocarcinoma without infiltration of the posterior hepatic branch in patients with impaired hepatic function.

A comparison of ultrasound, computed tomography and endoscopic retrograde cholangiopancreatography in the differential diagnosis of benign and malignant jaundice and cholestasis

OBJECTIVE

To assess the accuracy of ultrasonography (US), computed tomography (CT), and endoscopic retrograde cholangiopancreatography (ERCP) in distinguishing between benign and malignant causes of jaundice and cholestasis without jaundice.

DESIGN

Prospective study.

SETTING

University Hospital in Finland.

SUBJECTS

A consecutive series of patients with jaundice (n = 187) or cholestasis without jaundice (n = 33).

MAIN OUTCOME MEASURES

Correlation between diagnosis on imaging and final diagnosis at follow up 6 months later. Final diagnoses made on histology (n = 79), cytology (n = 5), operative or endoscopic findings (n = 96), and clinical course or serology (n = 40).

RESULTS

The most common benign disease was choledocholithiasis (n = 83) and the most common malignant disease was carcinoma of pancreas (n = 33). The benign nature of the extrahepatic obstruction was correctly defined by US, CT, and ERCP in 53%, 53%, and 90% of patients, respectively, and the corresponding figures for choledocholithiasis were 22%, 25%, and 79% (ERCP compared with each of the other techniques, p < 0.0001). Intrahepatic benign diseases were diagnosed by US and CT in a third of cases. Malignant extrahepatic obstruction was correctly diagnosed in 57%, 80%, and 83%, respectively and the corresponding figures for pancreatic cancer were 60%, 97%, and 89% (US compared with CT, p < 0.01, and with ERCP, p < 0.05). Intrahepatic malignant lesions were diagnosed by US, CT, and ERCP in 100%, 77%, and 60% of patients, respectively.

CONCLUSIONS

When the obstruction was benign and extrahepatic ERCP was the most accurate, but when it was malignant CT was comparable. Intrahepatic disease was best diagnosed by US and CT. The results emphasise that the three methods of imaging are complementary.

Endosonography in the clinical staging of Klatskin tumor

Endosonography was performed preoperatively in 46 patients with carcinoma of the common hepatic duct and its bifurcation. The results of endosonography were correlated with findings during surgery and pathological examination of the resected specimen and classified according to the new (1987) TNM classification. Overall accuracy in assessing the depth of tumor infiltration was 86.0%. Endosonography was accurate in predicting the presence of lymph nodes but not accurate in defining non-metastatic changes of lymph nodes. Staging of distant metastases was not accurate due to the low penetration depth of ultrasound.

Parenchymal changes of the liver in cholangiocarcinoma: CT evaluation

We evaluated parenchymal changes of the liver in 92 patients (41 peripheral types and 51 hilar types) with cholangiocarcinomas studied by bolus-enhanced computed tomography (CT). In 39% of patients with the peripheral type, a wedge-shaped increased enhancement of the liver was observed peripheral to the tumor on bolus-enhanced CT. Tumor was observed in all cases. In 58.8% of patients with the hilar type, a segmental or lobar increased degree of enhancement of the liver was observed, but the tumor was demonstrated in only 58.8%. Atrophy was accompanied by areas of increased enhancement in 80% of hilar type and 25% of peripheral type. Areas of increased degree of enhancement corresponded to a wedged-shaped perfusion defect on CT during arterial portography. On magnetic resonance imaging (MRI), those lesions showed hyperintensity on T2-weighted images. Most of these changes were considered to be due to reversible hepatic parenchymal ischemia secondary to portal vein invasion by the tumor.

Lymphadenopathy in sclerosing cholangitis: pitfall in the diagnosis of malignant biliary obstruction

We retrospectively reviewed abdominal computed tomographic (CT) studies from 20 patients with sclerosing cholangitis and found evidence of abdominal lymphadenopathy in 13 patients. Enlargement occurred primarily in areas draining the liver, such as the gastrohepatic ligament or celiac axis (N = 8), the porta hepatis (N = 7), and the pancreaticoduodenal region (N = 2). One patient had reactive adenopathy and retroperitoneal fibrosis. The presence of benign reactive lymphadenopathy in at least one intraabdominal location was confirmed by pathological examination of excised lymph nodes in seven patients. Malignancy was excluded by surgical exploration or clinical follow-up. We conclude that enlarged lymph nodes are a common finding by CT in patients with sclerosing cholangitis. Enlarged reactive lymph nodes in this condition should not be mistaken for evidence of periportal metastasis or cholangiocarcinoma.

Intermittent jaundice by tumor emboli from intrahepatic cholangiocarcinoma

Free-floating tumor debris or mucobilia as a cause of intermittent obstruction has been described infrequently. A patient with intermittent jaundice caused by tumor emboli from an intrahepatic polypoid mucinous cholangiocarcinoma is presented. Symptoms of intermittent jaundice and midepigastric pain persisted over 5 years despite an initial cholecystectomy and common bile duct exploration before definitive diagnosis and treatment of an hepatic trisegmentectomy (segments II, III, and IV). Intraductal mucin was confirmed intraoperatively and pathologically as the cause of the obstructive jaundice. The patient remains asymptomatic and without evidence of disease more than 5 years postoperatively. This report of a predominantly mucin-producing intrahepatic cholangiocarcinoma details a rare protracted clinical course of intermittent biliary obstruction from mucus emboli and highlights the possibility of long-term survival after complete resection.

Hepatic parenchymal perfusion defects detected with CTAP: imaging-pathologic correlation

To determine whether characteristics of focal hepatic parenchymal perfusion defects detected with computed tomographic arterial portography (CTAP) correlate with underlying pathologic processes, 245 perfusion defects detected with CTAP in 60 patients who subsequently underwent definitive hepatic surgery were characterized by shape, location within the liver, and relative attenuation value and were prospectively correlated with sectioned pathologic specimens. Of 177 round perfusion defects, 102 (58%) were malignant and 75 (42%) were benign. Only one (2%) of 53 peripheral wedge-shaped defects was malignant. All 15 peripheral flat defects were benign. Defects in characteristic locations anterior to the porta hepatis (n = 15) and adjacent to the intersegmental fissure (n = 7) were uniformly benign. While 83 (56%) of 147 soft-tissue attenuation defects were malignant, only four (6%) of 68 intermediate-attenuation defects were malignant. Although these characteristics of parenchymal perfusion defects aid in differentiation of benign from malignant processes, all other types of perfusion defects are nonspecific and may require biopsy.

Staging of hilar cholangiocarcinoma by ultrasound and duplex sonography: a comparison with angiography and operative findings

The pre-operative radiological assessment of proximal bile duct tumours is clinically important as resection may be limited by tumour extension along the bile ducts, into hepatic parenchyma or the adjacent vascular structures. Demonstration of the extent of biliary and vascular involvement can direct additional investigations and definitive treatment. 22 patients with hilar cholangiocarcinoma were studied pre-operatively by conventional ultrasound (US) and duplex sonography (DS). The extent of tumour infiltration and vascular involvement was compared with arteriography and operative findings. Bile duct dilatation and the level of obstruction was documented by US in 22 (100%), and the tumour was shown by US in 19 (86%). In these 19 patients, the extent of extraductal extension compared with operative findings was correct in 13, underestimated in two, and in four infiltration was massed. Vascular patency or involvement was correctly determined by DS in 19 (86%), and by arteriography in 18 (82%). In two of the three incorrect DS interpretations, lobar atrophy and contralateral hypertrophy distorted the hilar anatomy. US with DS is valuable in the pre-operative staging of proximal bile duct tumours in predicting ductal and vascular involvement.

[Liver angiography--technique, indications and significance in focal liver processes]

Retrospective analysis of 155 liver angiographies and the literature data was carried out to appraise the current relevance of liver angiography in digital subtraction technique (i.a. DSA) for diagnosis of focal liver changes. A focal liver lesion was detected by angiography in 58 out of the 80 patients (72.5%) we investigated with a confirmed hepatic space occupation; an angiography correlate of the tumour type diagnosed was shown in 41 out of 69 (59.4%) of malignancies confirmed by surgery or biopsy histology; in the benign lesions, the angiographic diagnosis was consistent with the histological result in five out of six cases. DSA is thus usually clearly inferior to the tomographic sonography, CT and MRI in detection and qualification of the tumour type. However, it is still indispensable for planning operations or chemoembolization and for exact imaging of the portal perfusion conditions because of the frequent vascular anomalies in the anatomy of the liver.

Malignant biliary obstruction: efficacy of thin-section dynamic CT in determining resectability

OBJECTIVE

Several authorities advocate the use of preoperative angiography to determine the resectability of pancreatic and periampullary tumors, claiming that CT alone is not sufficiently accurate for this purpose. Our objective was to assess the value of CT in predicting surgical resectability in patients with malignant biliary obstruction.

MATERIALS AND METHODS

We performed a retrospective analysis of 380 consecutive cases of malignant biliary obstruction spanning a 4-year period. Most patients (230) were treated nonoperatively. Sixty-seven patients had surgery, pathologic confirmation of malignancy, and preoperative CT scans available for review. The CT scans were assessed for surgical resectability of tumor by an interpreter who did not know the patient's history.

RESULTS

Forty-two patients had pancreatic adenocarcinoma, six had ampullary carcinoma, seven had cholangiocarcinoma, and 12 had other malignant neoplasms. Of 47 patients with tumors thought to be unresectable on the basis of CT findings, 42 had tumors that were found to be unresectable at surgery (positive predictive value, 89%). Of 20 patients with tumors thought to be resectable, 16 had tumors that were surgically resectable (positive predictive value, 80%). CT did not show metastases to duodenal lymph nodes (n = 2), portal vein infiltration (n = 1), and small hepatic metastases (n = 1). Visualization of most of these at angiography would not be expected. The CT finding of infiltration of the periarterial fat around the celiac or superior mesenteric arteries was reliable for predicting surgical unresectability. Lymphadenopathy and infiltration of nonperivascular fat planes were less reliable predictors of unresectability.

CONCLUSION

Although some findings on CT that suggest unresectability are less reliable than others, the accuracy of CT compares favorably with reports on the accuracy of angiography for assessing tumor resectability in cases of malignant biliary obstruction. The addition of angiography to the examination of patients with potentially resectable lesions is not justified when high-quality, thin-section dynamic CT has been performed.

Ultrasonographic patterns of hepatobiliary mass lesions

The study deals with an analysis of ultrasonographic (USG) patterns in 100 consecutive patients with hepatobiliary mass lesions. Amoebic liver abscess, carcinoma (CA) gall bladder and secondaries in liver comprised nearly 70% of cases. USG appearances in liver abscess, hepatoma, secondaries in liver and CA gall bladder were variable, but were characteristic in hydatid disease and congenital polycystic disease. Two patients with cholangiocarcinoma revealed dilated biliary channels with an intraluminal mass in common bile duct.

Hilar cholangiocarcinoma. An evaluation of subtypes with CT and angiography

Sixty-seven patients had hilar cholangiocarcinomas which were divided into 3 types based on tumor morphology as observed on cholangiography and CT. The pathology, vascularity, and pattern of tumor spread of these types were compared. Most of the infiltrative tumors (n = 44) were scirrhous adenocarcinomas, which on CT showed poor or no contrast enhancement with frequent lymph node metastases and liver atrophy. At angiography, there was vascular encasement in 52%, in rare cases neovascularity, and tumor stain. The exophytic type (n = 19) was divided into 2 subgroups depending on the main location of the tumor. The nodular subtype (n = 16) was mainly inside the liver and somewhat hypervascular similar to peripheral cholangiocarcinoma, often with intrahepatic metastases. The periductal subtype (n = 3) was hypovascular, similar to the infiltrative cholangiocarcinoma, and had a tendency to spread along the portal vein. The intraductal type (n = 4) was observed as a filling defect on cholangiography. CT revealed an intraluminal low density mass. Histologically, they were papillary adenocarcinomas. The radiologic types of hilar cholangiocarcinoma showed different characteristics with regard to pathologic findings, vascularity, and pattern of spread.

Distinction of hemangiomas from hepatic tumors with delayed enhancement by incremental dynamic CT

To analyze the patterns of contrast enhancement and to evaluate clinical utility, we performed table incremental dynamic CT in 21 patients with 30 hepatic hemangiomas and in 12 patients with 26 malignant neoplasms, which showed delayed enhancement. On incremental CT, dense, spotty peripheral enhancement was present in 23 of the 30 (77%) hemangiomas. In contrast, a circumferential bead- or band-like peripheral enhancement was seen in 19 of 26 (73%) malignant neoplasms. The findings were characteristic. We conclude that incremental CT is useful in the differential diagnosis of hepatic hemangioma in routine examination.

Delayed enhancement of fibrotic areas in hepatic masses: CT-pathologic correlation

We report a histological analysis of the areas of high density in the postequilibrium and delayed phase CT in 43 focal hepatic lesions. The cases consisted of 16 cholangiocellular carcinomas, 9 hepatocellular carcinomas (including a sclerosing type of hepatocellular carcinoma and a combined hepatocellular-cholangiocellular carcinoma), 13 metastases, 2 granulomas, an inflammatory pseudotumor, a malignant lymphoma, and an epithelioid hemangioendothelioma. Computed tomography was performed after hepatic angiography using 40-50 g iodine and arteriographic CT using 35 g iodine. The areas of delayed enhancement corresponded histologically to fibrotic tissues, from inflammatory change to extensive fibrosis.

Evaluation of liver tumors using fluorine-18-fluorodeoxyglucose PET: characterization of tumor and assessment of effect of treatment

To evaluate glucose metabolism in patients with tumors involving the liver, 35 patients with liver lesions had PET using 18F-2-fluoro-2-deoxy-D-glucose (FDG). FDG (148 MBq) was injected and radioactivity of the tumor was scanned dynamically by PET. The rate constants (k1, k2, k3, k4) of FDG in a metabolic model were calculated. The results were compared to hexokinase activity in the excised tumor specimens. k3 was found to reflect tumor hexokinase activity. When k3 was used as an index (cut-off value: 0.025), it was possible to distinguish benign and malignant tumors. k4 was significantly higher in hepatocellular carcinoma. By using k3 and k4 as indices, one could assess the degree of differentiation of hepatocellular carcinoma. After treatment, k3 decreased according to the effectiveness of therapy and thus may be a useful index for quantitatively assessing tumor viability.

Patency of side branches after peripheral placement of metallic biliary endoprostheses

During a 28-month period, the authors placed 91 Wallstent endoprostheses in 55 patients with malignant obstructive jaundice. Five patients developed recurrent jaundice between 2 and 60 weeks after stent insertion due to stent occlusion by tumor overgrowth on seven occasions. To assess long-term segmental side-branch drainage through the walls of such endoprostheses, the cholangiograms obtained following stent occlusion were reviewed. In all five patients, evidence of drainage of intrahepatic ducts through the side of the mesh was observed. Although the number of patients in the series is small, this initial experience suggests that long metallic endoprostheses can be placed peripherally in the intrahepatic bile ducts without the potential risk of infection or occlusion of undrained, noninvolved segments. This policy may delay or prevent endoprosthesis occlusion in many patients.

Relationship between intensity of Opisthorchis viverrini infection and hepatobiliary disease detected by ultrasonography

Twenty-four locality-, age- and sex-matched groups of village residents with no light, moderate and heavy Opisthorchis viverrini infection were examined by ultrasonography. Highly significant differences were observed between the groups in the relative size of the left lobe of the liver and the fasting and post-meal size of the gall-bladder. In addition, indistinct gall-bladder wall, the presence of gall-bladder sludge and strongly enhanced portal vein radicle echoes were most frequently observed in the heavily infected group. Two suspected cases of cholangiocarcinoma were identified from the heavy group. The results highlight the importance of intensity of infection on the frequency and severity of fluke-associated hepatobiliary disease.

Labelled antibody imaging in pancreatic cancer, cholangiocarcinoma, chronic pancreatitis and sclerosing cholangitis

Pancreatic and biliary carcinomas are difficult to differentiate clinically from their benign counterparts, chronic pancreatitis and sclerosing cholangitis. Immunohistochemical differences in CEA expression have previously been demonstrated in these conditions. We have therefore investigated the use of a monoclonal anti-CEA antibody (11-285-14) in distinguishing between these conditions in vivo. Twenty-five patients with these four conditions underwent radioimmunolocalisation studies. Diagnosis was confirmed by laparotomy and biopsy (n = 21), CT scanning (n = 1) or ERCP (n = 3). Positive images were obtained in 11/12 pancreatic cancers and 2/3 biliary tumours. However, 4/8 cases of chronic pancreatitis and 1/2 cases of sclerosing cholangitis also had positive images. This high false positive rate suggests that antibody imaging is unable to differentiate reliably between benign and malignant pancreatico-biliary conditions.