The diagnostic and treatment characteristics of focal liver lesions using computed tomography

Under analysis is an experience with examining and treatment of 167 patients with focal lesions of the liver using computed tomography. Percutaneous transhepatic puncture and draining the hepatic abscesses and cysts under control of computed tomography is an independent method of treatment used in 53 patients. The technique of performing the puncture and drainage is described. Specific features of surgical treatment of focal lesions of the liver are described. Decompression of bile ducts in the postoperative period is shown to be necessary. A conclusion is made about high efficiency of computed tomography in diagnosis and treatment of focal lesions of the liver.     

Limbic frontal cortex in hominoids: a comparative study of area 13

Because intraoperative sonography displays segmental anatomy, allows discovery of more lesions than previously suspected from preoperative imaging, surgical inspection, or palpation, and permits more certain diagnosis of problematic masses, it facilitates surgical decision-making when liver resection or cryoablation is anticipated. Intraoperative sonography provides a guidance modality to accurately place cryosurgery probes in liver masses. More precise treatment of metastatic and primary tumors of the liver is possible with cryoablation because intraoperative sonography provides a means of monitoring the growth of the enlarging freeze zone to insure adequate surgical margins. Postoperative detection of acute complications after cryosurgery is best done with computed tomography. Normally cryosurgery defects shrink with time and lose the peripheral contrast opacification seen after surgery. Gas collections, seen as a result of tissue necrosis, must be discriminated from infection. Tumor recurrence can be detected well with computed tomography or magnetic resonance imaging following hepatic cryosurgery.     

Limited value of fluorine-18-fluorodeoxyglucose PET for the differential diagnosis of focal liver lesions in patients with chronic hepatitis C virus infection

AIM: The differentiation of HCC from liver metastasis or benign disorders by imaging studies based upon morphological aspects may be difficult. METHOD: In order to evaluate the role of tumour metabolism, we performed FDG-PET (whole-body PET and transmission-corrected regional scans of the liver as well as the SUV determined 60 min after injection of FDG) in ten consecutive patients with HCV-associated focal liver lesions. Definite diagnosis was established after ultrasound-guided liver biopsy followed by histopathological examination. These results were compared with ultrasound, computed tomography, serum anti-p53, and p53 protein expression. RESULTS: The histologic examination revealed a HCC in five patients, regenerative nodules in three patients, and liver metastasis (primary malignancy: one adenocarcinoma and one neuroendocrine tumour) in the remaining two patients. Three of ten lesions were detectable by FDG-PET: two HCCs and one metastatic adenocarcinoma. Seven lesions were not distinguishable by FDG-PET (three HCCs, three regeneration nodules and one metastatic neuroendocrine tumour). In each patient hepatic lesions were visible either by ultrasound or CT. Both tumours (metastatic adenocarcinoma, moderately well-differentiated HCC) with the strongest expression of p53 also presented with highly increased FDG uptake. CONCLUSIONS: FDG-PET is not superior to ultrasound or CT and therefore does not allow the non-invasive differentiation of HCV-associated focal liver lesions. Tissue-diagnosis by means of liver-biopsy followed by histopathological examination remains the gold-standard for the differentiation of HCV-related liver lesions. The finding of the relationship of p53 protein overexpression with the SUV needs further confirmation.     

Small angiomyolipoma of the liver diagnosed by fine-needle aspiration biopsy under ultrasound guidance

The first reported case of small hepatic angiomyolipoma to be diagnosed by fine-needle aspiration biopsy (FNAB) is described. A 53 year old man presented with a tumour in segment VI of the liver measuring 0.9 x 0.8 cm. The tumour was hyperechoic on ultrasound examination, showed relatively low density (+ 33 Hounsfield units) on computed tomography (CT), and was hypervascular on angiography. Computed tomography during arterial portography demonstrated a perfusion defect. Magnetic resonance imaging (MRI) revealed high intensity by both T1- and T2-weighted imaging. Diagnosis could not be obtained by these imaging modalities, but it was established successfully by FNAB under ultrasound guidance. Histologically, the tumour was an angiomyolipoma made up of three components: blood vessels, smooth muscle and fatty tissue. Surgery is unnecessary for this benign condition, and the patient has been followed up. Ten months later, the patient is currently doing well without growth of the hepatic angiomyolipoma.     

Correlative imaging of the liver and hepatobiliary system

Many imaging techniques can be used to assess the liver and hepatobiliary system. Each modality has individual strengths and limitations, which usually vary depending on the specific clinical situation. This review discusses several specific common clinical situations where imaging of the liver and biliary system is necessary and describes the various imaging options. Space-occupying liver lesions are discussed, and particular attention is paid to the assessment of liver metastasis, hepatoma, and incidentally discovered liver lesions such as hemangioma, adenoma, and focal nodular hyperplasia. The value of ultrasound, computed tomography, magnetic resonance imaging, and scintigraphic techniques in this patient population is described. Isolated sulfur colloid hepatic scintigraphy is not of great value in the evaluation of these patients. Therefore, this review describes in some detail the value of physiological liver scintigraphy, including gallium and iminodiacetic acid (IDA) scanning as well as dynamic flow imaging of the liver such as hepatic artery perfusion scintigraphy and tagged red cell scintigraphy. Imaging of the biliary tree also is described. The roles of ultrasound and scintigraphy are compared and contrasted as related to the diagnosis of acute cholecystitis, common duct obstruction, and postoperative complications.     

Clinical applications of fusion imaging in oncology

Recent developments in tumor imaging, made possible by advances in instrumentation and radiopharmaceuticals, has led to an increasing need for accurate anatomic correlation of single photon emission computed tomography (SPECT) and positron emission tomography (PET) images. Fusion imaging permits the functional strengths of SPECT and PET to be combined with the anatomic resolution of computed tomography (CT) and magnetic resonance imaging (MRI). Clinical applications of fusion imaging include the evaluation of brain tumors, lymphoma, hepatic lesions and monoclonal antibody studies. The continued development of these techniques will eventually allow fusion imaging to become a routine part of nuclear medicine practice.     

Blunt rupture of the right hemi-diaphragm with complete dislocation of the right hepatic lobe: report of a case

We present herein a case of blunt rupture of the right hemidiaphragm occurring with complete intrathoracic dislocation of the right hepatic lobe in a polytraumatized patient. The initial chest X-ray was interpreted as right-sided hemothorax, and a thoracic drainage tube was accidentally placed into the liver. A computed tomography scan subsequently revealed diaphragmantic rupture with intrathoracic liver dislocation. It was possible to reposition the liver, and the extended dorsal diaphragmatic rupture was closed primarily through an abdominal approach. The problems associated with the diagnosis and operative treatment of fresh right-sided blunt traumatic diaphragmatic ruptures are discussed following this case report.     

Hepatocellular carcinoma presenting as a tumour of the hilar and extrahepatic bile ducts

A case of hepatocellular carcinoma extending within the large extra- and intrahepatic bile ducts is reported. No primary tumour was found in the liver parenchyma by abdominal ultrasound, spiral computed tomography or magnetic resonance, but transduodenal cholangioscopy showed tumour in the common hepatic ducts and the two main branches. Endoscopic biopsy showed highly differentiated hepatocellular carcinoma. The patient was treated with endoscopic biliary drainage and died at home 7 months after admittance.     

Magnetic resonance imaging in 80 cases of orbital tumors

Magnetic resonance imaging (MRI) is a new medical imaging technique which has been used in evaluating ocular and orbital diseases in recent years. Owing to the high resolution of soft tissues and lesions, it is superior to ultrasound and computed tomography in the localization and characterization of an orbital tumor in diagnosis. In this paper, we analysed 80 cases of MR images of orbital tumors by which all the lesions were detected. Benign or malignant disorders were recognized in 59 cases and complete tumors with accurate localization were shown in 79 cases. The principles of MRI, signal intensity of various tumors and the indications of MRI were discussed.     

Hypogenesis of right hepatic lobe accompanied by portal hypertension: case report and review of 31 Japanese cases

We report a rare case of hypogenesis of the right lobe of the liver with portal hypertension and a review of 31 cases of agenesis or hypogenesis of the right hepatic lobe reported in Japan. A 74-year-old man consulted our hospital for further examination after a mass screening for gastric cancer. On physical examination liver enlargement was palpable, but liver function tests were normal. Abdominal ultrasonography, computed tomography, technetium-99m liver scintigraphy, and endoscopic retrograde cholangiopancreatography revealed a small right hepatic lobe and moderate splenomegaly, in contrast to a hypertrophic lateral segment of the left hepatic lobe, as well as ectopic dislocation of the gallbladder. Endoscopic examination revealed esophageal varices, indicating portal hypertension. Abdominal angiography demonstrated mild shunt flow between the hepatic artery feeding from the gastroduodenal artery and the portal vein. A biopsy specimen taken from both lobes of the liver showed normal liver tissue histologically. Based on these findings, we made a definite diagnosis of hypogenesis of the right lobe of the liver with portal hypertension. The present case appears to be the first such case accompanied by portal hypertension reported in Japan.     

Imaging of follicular dendritic cell tumours of the liver

Follicular dendritic cell tumour of the liver is a recently recognized entity. To date, only two cases have been described, both in the pathology literature. Histologically, it resembles an inflammatory pseudotumour and immunohistochemical and ultrastructural studies are required for its diagnosis. The ultrasound, computed tomography and angiographic features of two cases of follicular dendritic cell tumour of the liver are described in detail. One of the patients had multiple recurrences of this tumour. The imaging features are very similar to those of hepatocellular carcinoma. As follicular dendritic cell tumour is considered to be of low-grade malignant potential, in contrast to the dismal prognosis for hepatocellular carcinoma, it is important to be able to accurately distinguish between the two types of tumour prior to initiating definitive therapy.     

Hepatic hemangioma. Analysis of 103 cases. Clinical considerations and imaging methods

Hemangiomas are the most common benign vascular tumor found in the liver. In this study, 103 cases of hepatic hemangiomas were analysed in a retrospective manner. Image aspects such as those seen in ultrassonography, computed tomography, nuclear magnetic resonance and arteriography are discussed. The incidence was higher amongst the female sex, between individuals from 40 to 60 years old, which presented predominantly without symptoms (66%) and localized mainly in the right hepatic lobe (74%). The meaning of those aspects, when adopted, permits the clinicians to differentiate benign from malignant nodular lesions in the liver.     

Whole-body [18F]FDG PET in the management of metastatic brain tumours

BACKGROUND: To determine its roles in the diagnosis and the systemic evaluation of metastatic brain tumours, whole-body positron emission tomography (PET) using [18F]FDG was performed in 20 consecutive patients. METHODS: All patients were thought to be suffering or needing to be differentiated from metastatic brain tumours. Nine patients had multiple brain lesions; six were older and showed a rim-enhancing lesion with surrounding oedema; seven had homogeneously enhancing periventricular lesion(s) on computed tomography (CT) and/or magnetic resonance (MR) imaging, thought to be central nervous system lymphomas. Two patients had skull mass(es) and two patients had a solid mass suspected to be, respectively, a haemorrhagic metastasis and a metastatic malignant melanoma. All of them received whole-body [18F]FDG PET and conventional systemic work-up for metastasis in order to compare the results of the two methods. RESULTS: Metastatic brain tumours were diagnosed on whole-body [18F]FDG PET in eleven patients who had extracranial and intracranial hypermetabolic lesions. In nine of these, a conventional work-up also detected primary lesions which on whole-body [18F]FDG PET were seen to be hypermetabolic foci. Systemic lymph node metastases were detected by whole-body [18F]FDG PET only in two patients and histological diagnosis was possible by biopsy of lymph nodes rather than of brain lesions. In the remaining nine patients who had only intracranial hypermetabolic foci, histological diagnosis was made by craniotomy or stereotactic biopsy. It was confirmed that seven of nine patients were suffering from a primary brain tumour and two from metastatic carcinoma. None of the nine showed evidence of systemic cancer on conventional work-up. Histological diagnoses of the primary brain tumours were four cases of primary central nervous system lymphoma and one each of multifocal glioblastoma, Ewing's sarcoma, and cavernous angioma. Patients felt no discomfort during the whole-body [18F]FDG PET procedure and there were no complications. The false negative rate in [18F]FDG PET and in conventional work-up was 15.4% and 30.7% respectively. There were no false positives on either [18F]FDG PET or conventional work-up. CONCLUSION: It is suggested that whole-body [18F]FDG PET is a safe, reliable, and convenient method for the diagnosis and systemic evaluation of patients thought to be suffering or needing to be differentiated from a metastatic brain tumour.     

Preventive effects of superoxide dismutase derivatives modified with monosaccharides on reperfusion injury in rat liver transplantation

Focal nodular hyperplasia (FNH) and adenoma are rare benign hepatic tumors, and the standards for diagnosis and treatment still remain controversial. Usually adenoma is an indication for resection, due to its tendency to bleed and to degenerate; FNH, on the contrary, may be treated conservatively. Preoperation differential diagnosis is, however, difficult, often impossible. MATERIALS AND METHODS: Thirty-eight patients with presumed hepatic adenoma and/or FNH were studied at our department from 1984 to 1996. Preoperative assessment included clinical evaluation and symptoms, laboratory tests, liver biopsy, ultrasound scan, computed tomography scan, magnetic resonance imaging, scintigraphy, and angiography. Thirteen patients had a presumed diagnosis of FNH, 16 of adenoma, and 9 of undetermined benign lesions; 27 had hepatic resections (3 with laparoscopic technique), and 11 were not operated on and are actually under a strict follow-up observation. RESULTS: The final diagnosis was 19 FNH and 19 adenomas (2 of which contained areas of hepatocarcinoma). Presumed diagnosis was confirmed in 71% of cases. Use of oral contraceptives, abdominal symptoms, and pathologic liver test results were frequent in patients with adenomas. There were no deaths after surgery. All resected patients were tumor free during the follow-up, and in 10 of the 11 nonoperated cases, the size of the nodules remained unchanged. We conclude that precise diagnosis of these benign liver tumors remains difficult and sometimes impossible, despite new imaging techniques. Hepatic resections can be performed under very safe conditions; laparoscopic surgery may play a role in selected cases. Adenomas and uncertain cases are clear indications for surgery. Only when a diagnosis of FNH can be firmly confirmed in asymptomatic patients is strict observation without surgery recommended.     

Snake and spider antivenin: risks and benefits of therapy

A case of hepatic mesenchymal hamartoma, found after sudden onset clinical and biological cholestasis, is reported in a 18-year-old man. Abdominal ultrasound examination and computed tomography showed a intrahepatic cystic tumor. The diagnosis of hepatic mesenchymal hamartoma was made by the pathological examination of the resected specimen. This rare tumor is found in most cases in children less than 2 years old. Thirteen cases in adulthood were already reported, five of them in Japanese patients. Our case is peculiar because no hepatic tumor was shown by ultrasound examination, 2 years before, the large size of cysts and presence of smooth muscle fibers in the wall.     

Patterns of oncogene activation in human neuroblastoma cells

The authors report 7 cases of intestinal carcinoids. They examine the clinical aspects and describe and discuss both surgical and medical treatment strategies. They also critically evaluate the value of monitoring some oncological markers and their prognostic significance. Each patient underwent an in-depth evaluation of tumour evolution (CAT, ultrasonography, NMR, angiography) and urinary 5HIAA and platelet 5HT were monitored. Surgery took the form of ileal or ileocolic resection, gastric resection, exeresis of the tumour using a transanal route, ligature of the right branch of the hepatic artery afferent to the metastasised lobe of the liver. Five patients were treated using chemotherapy and three, also suffering from carcinoid syndrome, with octreotide. On the basis of their personal experience the authors underline the limited value of the study of 5HT and 5HIAA tumour markers in the diagnosis of small carcinoid tumours. This is compensated by the outstanding role of these markers in the diagnosis of the hepatic and/or lymphoglandular diffusion of the tumour. These markers were not influenced by octreotide treatment in cases in which longastatin was successfully used to combat carcinoid syndrome. Their behaviour allowed useful information to be acquired regarding the tumour evolution following surgery.     

Primary intraosseous meningiomas of the skull

The plain film, computed tomography (CT) and angiographic findings in 10 patients with primary intraosseous meningioma were reviewed and the differential diagnosis considered. In nine patients with benign primary intraosseous meningioma, the radiological findings revealed intraosseous expansile growth. In one patient with the malignant form of the tumour, osteolytic growth was evident on plain film and CT. In eight patients, the tumour tissue was hyperdense (65-85 HU) on the unenhanced CT images and striking enhancement was shown in seven. In five patients angiography showed that the external carotid artery fed the tumour, while in one the vasculature was normal. Benign primary intraosseous meningioma showed expansile growth and malignant tumour showed osteolytic growth. If a combination of the plain film, angiogram and CT findings is considered, a diagnosis of the benign tumour can be made and a diagnosis of benign meningioma can be suggested.     

Measurement of response to treatment in colorectal liver metastases

Assessment of tumour response to chemotherapy is important when assessing efficacy of treatment and comparing differing therapeutic regimens. Percentage hepatic replacement (PHR) is commonly used to assess response to treatment of colorectal hepatic metastases. PHR is dependent not only on tumour volume, but also on hepatic parenchymal volume. The effect of tumour growth on hepatic parenchymal volume is unclear but is of importance owing to its effect on PHR. We assessed tumour and hepatic parenchymal weights in an animal tumour model using dissection, and tumour and hepatic parenchymal volumes in patients with colorectal hepatic metastases using CT scanning, in order to establish how hepatic parenchyma varied with change in metastasis size. There was no significant correlation between tumour and liver parenchyma in either the animal model (r = -0.03, P > 0.05) or the patient study (r = 0.3, P < 0.05). This suggests that hepatic parenchymal volume was preserved in the presence of increasing tumour volume. In a further study of computerised tomographic (CT) scans before and after treatment in patients whose tumours either responded to chemotherapy or continued to grow, change in PHR (median proportion of PHR change = 0.40) significantly (P = 0.04) underestimated the change in tumour volume (median proportion of tumour volume change = 0.56), particularly at higher (> 400 ml) volumes. There was good correlation between change in tumour volume and WHO criteria in assigning patients to tumour growth, stable disease or tumour response categories. This study suggests that, in clinical trials comparing colorectal liver metastasis treatments, metastasis volume and not PHR should be used to assess extent of disease and the effect of treatment.     

Liver CT: a practical approach to dynamic contrast enhancement

The aim of this study was to establish a practical, simple protocol that reliably produces high quality dynamic incremental computed tomography (CT) of the liver. We reviewed 90 patients randomly allocated into six different protocols. All had preliminary unenhanced scans followed by a dynamic incremental CT of the liver. An initial delay of 30 seconds was used from the commencement of the injection of Iopamiro 370. The groups were: 1. Pump infusion (a) 100 mls at 2 mls/sec scanning inferosuperiorly. (b) 100 mls at 2 mls/sec scanning superoinferiorly. (c) 100 mls at 1 ml/sec scanning inferosuperiorly. (d) 50 mls at 1 ml/sec scanning inferosuperiorly. 2. 40 mls hand injected bolus followed immediately by 60 ml pump infusion at 1.3 mls/sec scanning inferosuperiorly. 3. 50 mls hand injected bolus scanning inferosuperiorly. The parameters recorded were the degree of hepatic parenchymal and hepatic venous enhancement and the aortic--IVC difference at the last slice through the liver, all measured in Hounsfield units. The protocols using 100 mls of contrast produced approximately twice the parenchymal and hepatic venous enhancement compared with those using 50 mls. Approximately 60-90% of examinations using 100 mls produced scans through the entire liver during the bolus or nonequilibrium phase, deemed the most sensitive for the detection of focal lesions, compared with 13-33% of those using 50 mls. Equally satisfactory results were obtained using the relatively inexpensive Biotel power injector preceded by a 40 ml hand injected bolus, compared with using an Angiomat angiography infusion pump.(ABSTRACT TRUNCATED AT 250 WORDS)     

Intracaval ultrasonography in the diagnosis of tumour involvement of the vena cava

A retrospective study of 34 consecutive patients with possible tumour involvement of the vena cava was performed to assess the usefulness of intracaval ultrasonography. Twenty-five of the 34 patients were operated and resection carried out in 23, including seven with combined resection of the vena cava. The sonographic criterion for vena cava invasion was obliteration of the echogenic ring of the vena cava wall or intracaval tumour mass. The sensitivity, specificity and overall accuracy of intracaval endovascular ultrasonography in the diagnosis of tumour involvement of the vena cava were 100, 96 and 97 per cent respectively. The respective values were 91, 61 and 71 per cent for computed tomography and 82, 67 and 72 per cent for cavography. Ultrasonography is a useful technique that can precisely evaluate the vena cava for possible tumour invasion, especially when the presence or extent of tumour involvement is not definitely established by conventional imaging techniques.