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Liver Mass (liver + mass)
Selected AbstractsAn inhibitor of cyclin-dependent kinase, stress-induced p21Waf-1/Cip-1, mediates hepatocyte mito-inhibition during the evolution of cirrhosis,HEPATOLOGY, Issue 6 2005John G. Lunz III During the evolution of cirrhosis, there is a relative decrease in volume percentage of hepatocytes and a relative increase in biliary epithelial cells and myofibroblasts. This is recognized histopathologically as a ductular reaction and leads to gradual distortion of the normal hepatic architecture. The final or decompensated stage of cirrhosis is characterized by a further decline in hepatocyte proliferation and loss of functional liver mass that manifests clinically as ascites, encephalopathy, and other signs of liver failure. In this report, we tested the hypothesis that p21-mediated hepatocyte mito-inhibition accelerates the evolution of cirrhosis using an established mouse model of decompensated biliary cirrhosis, p21-deficient mice, and liver tissue from humans awaiting liver replacement. Despite the same insult of long-term (12-week) bile duct ligation, mice prone to decompensation showed significantly more oxidative stress and hepatocyte nuclear p21 expression, which resulted in less hepatocyte proliferation, an exaggerated ductular reaction, and more advanced disease compared with compensation-prone controls. Mice deficient in p21 were better able than wild-type controls to compensate for long-term bile duct ligation because of significantly greater hepatocyte proliferation, which led to a larger liver mass and less architectural distortion. Mito-inhibitory hepatocyte nuclear p21 expression in humans awaiting liver replacement directly correlated with pathological disease stage and model of end-stage liver disease scoring. In conclusion, stress-induced upregulation of hepatocyte p21 inhibits hepatocyte proliferation during the evolution of cirrhosis. These findings have implications for understanding the evolution of cirrhosis and associated carcinogenesis. Supplementary material for this article can be found on the HEPATOLOGY website (http://interscience.wiley.com/jpages/0270-9139/suppmat/index.html). (HEPATOLOGY 2005.) [source] Cellular responses in experimental liver injury: Possible cellular origins of regenerative stem-like progenitor cells,HEPATOLOGY, Issue 5 2005William B. Coleman Ph.D. Background/Aims Mature hepatocytes divide to restore liver mass after injury. However, when hepatocyte division is impaired by retrorsine poisoning, regeneration proceeds from another cell type: the small hepatocyte-like progenitor cells (SHPCs). Our aim was to test whether SHPCs could originate from mature hepatocytes. Methods Mature hepatocytes were genetically labeled using retroviral vectors harboring the ,-galactosidase gene. After labeling, retrorsine was administered to rats followed by partial hepatectomy to trigger regeneration. A liver biopsy was performed one month after surgery and rats were sacrificed one month later. Results We observed the proliferation of small hepatocytes arranged in clusters in liver biopsies. These cells expressed Ki67 antigen and displayed high mitotic index. At sacrifice, regeneration was completed and clusters had merged. A significant proportion of clusters also expressed ,-galactosidase demonstrating their origin from labeled mature hepatocytes. Finally, the overall proportion of ,-galactosidase positive cells was identical at the time of hepatectomy as well as in liver biopsy and at sacrifice. Conclusions The constant proportion of ,-galactosidase positive cells during the regeneration process demonstrates that mature hepatocytes are randomly recruited to proliferate and compensate parenchyma loss in this model. Furthermore, mature hepatocytes are the source of SHPC after retrorsine injury. [source] Efficacy and limitation of bone marrow transplantation in the treatment of acute and subacute liver failure in ratsHEPATOLOGY RESEARCH, Issue 11 2009Hirotaka Tokai Aim:, Recent reports have shown that bone marrow cells (BMC) retain the potential to differentiate into hepatocytes. Thus, the BMC have been recognized as an attractive source for liver regenerative medicine. However, it has not been clarified whether BMC transplantation can be used to treat liver damage in vivo. In the present study, we explored whether BMC possess therapeutic potential to treat acute and/or subacute liver failure. Methods:, Fulminant hepatic failure (FHF) was induced by 70% hepatectomy with ligation of the right lobe pedicle (24% liver mass), followed by transplantation of BMC into the spleen. Dipeptidyl peptidase IV-positive (DPPIV+) BMC were then transplanted into DPPIV-negative (DPPIV - ) recipients following hepatic irradiation (HIR) in which 70% of the liver was resected and the remnant liver irradiated. Results:, There was no benefit of BMC transplantation towards survival in the FHF model. DPPIV+ hepatocytes appeared in the liver tissues of the DPPIV - HIR model rats, but DPPIV+ hepatocytes replaced less than 13% of the recipient liver. Conclusion:, BMC transplantation may have limitations in the treatment of fulminant or acute liver failure because they do not have sufficient time to develop into functional hepatocytes. Preparative HIR may be beneficial in help to convert the transplanted BMC into host hepatocytes, and provide a survival benefit. Although, However, the precise mechanism warrants further studies. [source] Regulatory processes interacting to maintain hepatic blood flow constancy: Vascular compliance, hepatic arterial buffer response, hepatorenal reflex, liver regeneration, escape from vasoconstrictionHEPATOLOGY RESEARCH, Issue 11 2007W. Wayne Lautt Constancy of hepatic blood flow (HBF) is crucial for several homeostatic roles. The present conceptual review focuses on interrelated mechanisms that act to maintain a constant HBF per liver mass. The liver cannot directly control portal blood flow (PF); therefore, these mechanisms largely operate to compensate for PF changes. A reduction in PF leads to reduced intrahepatic distending pressure, resulting in the highly compliant hepatic vasculature passively expelling up to 50% of its blood volume, thus adding to venous return, cardiac output and HBF. Also activated immediately upon reduction of PF are the hepatic arterial buffer response and an HBF-dependent hepatorenal reflex. Adenosine is secreted at a constant rate into the small fluid space of Mall which surrounds the terminal branches of the hepatic arterioles, portal venules and sensory nerves. The concentration of adenosine is regulated by washout into the portal venules. Reduced PFreduces the washout and the accumulated adenosine causes dilation of the hepatic artery, thus buffering the PF change. Adenosine also activates hepatic sensory nerves to cause reflex renal fluid retention, thus increasing circulating blood volume and maintaining cardiac output and PF. If these mechanisms are not able to maintain total HBF, the hemodynamic imbalance results in hepatocyte proliferation, or apoptosis, by a shear stress/nitric oxide-dependent mechanism, to adjust total liver mass to match the blood supply. These mechanisms are specific to this unique vascular bed and provide an excellent example of multiple integrative regulation of a major homeostatic organ. [source] Supra-elevated CA 19-9 in a benign hepatic cystadenomaHPB, Issue 1 2004CR Scoggins Background Elevated CA 19-9 may be found in both cystadenomas and cystadenocarcinomas of the liver. Case outline A 59-year-old woman presented with right upper quadrant abdominal pain, malaise and weight loss. Physical examination and laboratory evaluation revealed a mass in the right upper quadrant and a CA 19-9 level of 68 661 U/ml. CT scan demonstrated a cystic liver mass. She underwent a right hepatectomy, and her CA 19-9 returned to normal. Pathologic analysis revealed no malignancy. Discussion In hepatic cystic neoplasms, an elevated CA 19-9 should not be used to establish the diagnosis of malignancy nor should it preclude resection. [source] Oval cell proliferation in p16INK4a expressing mouse liver is triggered by chronic growth stimuliJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 2 2008Elke Ueberham Abstract Terminal differentiation requires molecules also involved in aging such as the cell cycle inhibitor p16INK4a.Like other organs, the adult liver represents a quiescent organ with terminal differentiated cells, hepatocytes and cholangiocytes. These cells retain the ability to proliferate in response to liver injury or reduction of liver mass. However, under conditions which prevent mitotic activation of hepatocytes, regeneration can occur instead from facultative hepatic stem cells. For therapeutic application a non-toxic activation of this stem cell compartment is required. We have established transgenic mice with conditional overexpression of the cell cycle inhibitor p16INK4a in hepatocytes and have provoked and examined oval cell activation in adult liver in response to a range of proliferative stimuli. We could show that the liver specific expression of p16INK4a leads to a faster differentiation of hepatocytes and an activation of oval cells already in postnatal mice without negative consequences on liver function. [source] Safety and efficacy of sonographic-guided random real-time core needle biopsy of the liverJOURNAL OF CLINICAL ULTRASOUND, Issue 3 2009Siddharth A. Padia MD Abstract Purpose. To determine the safety and efficacy of real-time, sonographic-guided, random percutaneous needle biopsy of the liver in a tertiary medical center. Method. From an IRB-approved biopsy database, all patients who had random liver biopsy performed over a 24-month period were selected. In 350 patients, 539 random percutaneous needle biopsies of the liver were performed under real-time sonographic visualization. The following were recorded from the electronic medical record: patient demographics, indication for biopsy procedure; radiologist's name; needle type and gauge and number of passes; use and amount of IV sedation or anesthesia; adequacy of the specimen; and complications following the procedure. Result. Of 539 biopsies, 378 (70%) biopsy procedures were performed on liver transplant recipients. Of the biopsy procedures in nontransplant patients, 81/161 (50%) concurrently underwent biopsy of a focal liver mass. An 18-gauge automated core biopsy needle was used in 536/539 (99%). Median number of passes per biopsy procedure was 1 (mean, 1.7; range, 1,6). Sedation using midazolam and fentanyl was used in 483/539 (90%). There were only 8 inadequate specimens (1.5%, [2.3, upper 95% confidence limit, fully described in Statistical Analysis]). Complications were identified in 11/539 biopsy procedures (2.0%, [2.6, upper 95% confidence limit]): 5 with severe postprocedural pain, 3 with symptomatic hemorrhage, 2 with infection, and 1 with a rash. There were no sedation-related complications and no deaths related to the procedure. Conclusion. Real-time, sonographic-guided, random core-needle liver biopsy is a safe and highly effective procedure. © 2009 Wiley Periodicals, Inc. J Clin Ultrasound 2009 [source] LIPID-LOWERING EFFECTS OF ARONIA MELANOCARPA FRUIT JUICE IN RATS FED CHOLESTEROL-CONTAINING DIETSJOURNAL OF FOOD BIOCHEMISTRY, Issue 5 2007S. VALCHEVA-KUZMANOVA ABSTRACT Aronia melanocarpa fruit juice (AMFJ) is very rich in phenolic antioxidants, mainly flavonoids from the subclass anthocyanins. The aim of this study was to assess the influence of AMFJ on body and liver mass, plasma lipids and lipoprotein profiles, and the histopathology of liver and aorta in rats fed with cholesterol diets. AMFJ was applied orally for 30 days at doses of 5, 10 and 20 mL/kg. In rats fed the cholesterol-containing diets, AMFJ significantly hindered an increase in plasma lipids (total cholesterol, low-density lipoprotein cholesterol and triglycerides) because of cholesterol feeding. Body weight gains, liver weights, and liver and aorta histopathology were not influenced either by high-cholesterol diets or by AMFJ treatment. In conclusion, AMFJ showed lipid-lowering effects in rats with experimentally induced hyperlipidemia, and could be valuable in reducing lipidemia as a factor of cardiovascular risk. PRACTICAL APPLICATIONS Hyperlipidemia characterized by an increase in low-density lipoprotein (LDL) cholesterol and a decrease in high-density lipoprotein cholesterol is one of the major risk factors for atherosclerosis and cardiovascular disease. Plant foods with high contents of phenolic phytochemicals are reported to be inversely correlated with plasma total cholesterol (TC) and LDL cholesterol. Aronia melanocarpa fruits are remarkably rich in phenolic substances. They are used for human consumption as juice, syrup, jam and wine. Our research demonstrated that A. melanocarpa fruit juice hindered the dietary-induced elevation of plasma TC, LDL cholesterol and triglycerides in rats. In view of the results from our experiment, we can suppose that the juice may be further tested for reducing hyperlipidemia in humans and possibly approved a valuable dietary supplement. [source] Hepatobiliary and pancreatic: A man with a large liver massJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 4 2001Article first published online: 21 DEC 200 No abstract is available for this article. [source] Evaluation of hepatotropic targeting properties of allogenic and xenogenic erythrocyte ghosts in normal and liver-injured ratsLIVER INTERNATIONAL, Issue 2 2008Olav A. Gressner Abstract Background/Aims: Haemoglobin-depleted erythrocyte ghosts have been recommended as vesicle carriers of drugs with hepatotropic properties. However, the influence of liver injury on ghost elimination and targeting has not been reported so far. Methods: Human and rat ghosts were prepared and loaded with model substances, and the basic parameters were characterized. Ghosts were injected intravenously into rats with acute, subacute and chronic liver injuries. Elimination from circulation, organ distribution and cellular targeting was measured. The uptake of ghosts by liver macrophages/Kupffer cells was determined in cell culture. Results: Ghosts are strong hepatotropic carriers with a recovery of 90% in normal liver. Kupffer cells are the almost exclusive target cell type. Hepatotropic properties remain in rats with chronic liver diseases, but are reduced by 60,70% in acute liver damage as a result of decline of phagocytosis of macrophages/Kupffer cells. Although the uptake of ghosts per gram liver tissue in chronic liver injury was also reduced by about 40%, the increase of liver mass and of macrophages/Kupffer cells compensated for the reduced phagocytotic activity. In subacute injury, the uptake per gram liver tissue was only moderately reduced. Conclusion: Drug targeting with ghosts might be feasible in chronic and subacute liver injuries, e.g. fibrogenesis and tumours, because the content of ingested ghosts is released by Kupffer cells into the micro-environment, providing the uptake by and pharmacological effects on adjacent cells. [source] Selective elimination of hepatic natural killer T cells with Concanavalin A improves liver regeneration in miceLIVER INTERNATIONAL, Issue 3 2006Wen Huang Abstract: Background: Although concanavalin A (Con A) as a T cell stimulant can cause natural killer T (NKT) cell-mediated liver injury in mice and a nonhepatotoxic dose of Con A can trigger innate immune cells including NKT cells to prevent tumor metastasis in the liver, little is known about the role of Con A-primed NKT cells in liver repair. In this study, we aimed to investigate the effect of pretreatment with a nontoxic dose of Con A on subsequent liver regeneration in mice. Methods: A nontoxic dose of Con A was injected intravenously 24 h before partial hepatectomy (PHx), which was used as a model of liver regeneration. Ratios of remnant liver mass to body weight, bromodeoxyuridine (BrdU) incorporation and proliferating cell nuclear antigen (PCNA) labeling were used to assess liver regeneration. Results: Hepatic mononuclear cells were isolated and analyzed by flow cytometry. After PHx, the ratios of liver weight to body weight, PCNA-positive hepatocytes and BrdU-positive hepatocytes in Con A-pretreated mice were significantly higher than that of phosphate-buffered saline-treated mice, indicating that Con A pretreatment can accelerate liver regeneration. Flow cytometric analysis showed that NKT cells were significantly activated and selectively eliminated after the Con A administration. Moreover, NKT cells expressed more apoptosis-related molecules, Fas and Annexin V. Conclusions: Taken together, Con A accelerates liver regeneration in mice by eliminating hepatic NKT cells via activation-induced cell death. [source] Simplified standardized technique for living donor liver transplantation using left liver graft plus caudate lobeLIVER TRANSPLANTATION, Issue 11 2004Shin Hwang Concomitant resection of the caudate lobe (CL) would increase the liver mass in the left liver graft. We tried to define a simplified standardized technique for adult living donor liver transplantation using the extended left lobe (ELL) plus CL (ELLC) through a prospective study of 27 consecutive ELLC graft cases in 2003. Donor CL was dissected toward the 10 o'clock direction and transected at the midpoint between the trunks of the right hepatic vein (RHV) and the middle hepatic vein (MHV). This orthodox transection was performed in 18 cases, but the transection plane was moved left in 9 cases. Compared with conventional left liver implantation, there was no additional reconstruction except for single revascularization of the largest short hepatic vein of the CL (V1) in 21 cases. On 1-week computed tomography (CT) images, the perfusion states of the CL portion were good in 15 cases, fair in 7 cases, and poor in 5 cases. Regeneration of the CL portion during the 1st week was +43%, +18%, and ,10% in the good, fair, and poor perfusion groups, respectively. There were positive correlations among the perfusion state of the CL, the location of the CL transection plane, and the width of the CL portion that was attached to the left liver graft. CL implantation resulted in a mean gain of graft mass by 5.9% in the left liver at the time of operation and by 3.9% after 1 week. There were no donor complications, and 25 recipients (93%) survive to date. In conclusion, this simplified standardized technique was feasible for most of the living donor livers and required only 1 additional reconstruction of the V1. (Liver Transpl 2004;10:1398,1405.) [source] Needle-tract implantation from hepatocellular cancer: Is needle biopsy of the liver always necessary?LIVER TRANSPLANTATION, Issue 1 2000Ryan Takamori Percutaneous needle biopsies are frequently used to evaluate focal lesions of the liver. Needle-tract implantation of hepatocellular cancer has been described in case reports, but the true risk for this problem has not been clearly defined. We retrospectively reviewed 91 cases of hepatocellular cancer during a 4-year period from 1994 to 1997. Data on diagnostic studies, therapy, and outcome were noted. Of 91 patients with hepatocellular cancer, 59 patients underwent percutaneous needle biopsy as part of their diagnostic workup for a liver mass. Three patients (5.1%) were identified with needle-tract implantation of tumor. Two patients required en bloc chest wall resections for implantation of hepatocellular cancer in the soft tissues and rib area. The third patient, who also received percutaneous ethanol injection of his tumor, required a thoracotomy and lung resection for implanted hepatocellular cancer. Percutaneous needle biopsy of suspicious hepatic lesions should not be performed indiscriminately because there is a significant risk for needle-tract implantation. These biopsies should be reserved for those lesions in which no definitive surgical intervention is planned and pathological confirmation is necessary for a nonsurgical therapy. (Liver Transpl 2000;6:67-72.) [source] Regional hydrodynamic gene delivery to the rat liver with physiological volumes of DNA solutionTHE JOURNAL OF GENE MEDICINE, Issue 6 2004Xiaohong Zhang Abstract Background The major barrier to the clinical application of hydrodynamic gene delivery to the liver is the large volume of fluid required using standard protocols. Regional hydrodynamic gene delivery via branches of the portal vein has not previously been reported, and we have evaluated this approach in a rat model. Methods The pGL3 plasmid with the luciferase reporter gene was used at 50 µg/ml in isotonic solutions, and was administered with a syringe pump for precise control of the hydrodynamic conditions evaluated. Gene expression was individually measured in six anatomically distinct liver lobes. The effect of systemic chloroquine to promote endocytic escape and a (Lys)16 -containing peptide to condense the DNA into ,100-nm nanoparticles was also evaluated. Results Hydrodynamic conditions for excellent gene delivery were obtained by using 3-ml volumes (,12 ml/kg) of isotonic DNA solution delivered at 24 ml/min to the right lateral lobe (,20% of the liver mass). Under these conditions, >95% of gene delivery usually occurred in the targeted right lateral lobe. Outflow obstruction was essential for gene delivery, both at optimal and at very low levels of hydrodynamic gene delivery. The use of systemic chloroquine to promote endocytic escape did not augment hydrodynamic gene delivery, while condensation of DNA in non-ionic isotonic solutions (5% dextrose) to nanoparticles of ,100 nm completely abolished gene delivery. Conclusions Regional hydrodynamic gene delivery via a branch of the portal vein offers a physiological model of liver gene therapy, for experimental and clinical application. Copyright © 2004 John Wiley & Sons, Ltd. [source] Progenitor cells in liver regeneration: molecular responses controlling their activation and expansion,APMIS, Issue 11-12 2005ERIC SANTONI-RUGIU Although normally quiescent, the adult mammalian liver possesses a great capacity to regenerate after different types of injuries in order to restore the lost liver mass and ensure maintenance of the multiple liver functions. Major players in the regeneration process are mature residual cells, including hepatocytes, cholangiocytes and stromal cells. However, if the regenerative capacity of mature cells is impaired by liver-damaging agents, hepatic progenitor cells are activated and expand into the liver parenchyma. Upon transit amplification, the progenitor cells may generate new hepatocytes and biliary cells to restore liver homeostasis. In recent years, hepatic progenitor cells have been the subject of increasing interest due to their therapeutic potential in numerous liver diseases as alternative or supportive/complementary tools to liver transplantation. While the first investigations on hepatic progenitor cells have focused on their origin and phenotypic characterization, recent attention has focused on the influence of the hepatic microenvironment on their activation and proliferation. This microenvironment comprises the extracellular matrix, epithelial and non-epithelial resident liver cells, and recruited inflammatory cells as well as the variety of growth-modulating molecules produced and/or harboured by these elements. The cellular and molecular responses to different regenerative stimuli seem to depend on the injury inflicted and consequently on the molecular microenvironment created in the liver by a certain insult. This review will focus on molecular responses controlling activation and expansion of the hepatic progenitor cell niche, emphasizing similarities and differences in the microenvironments orchestrating regeneration by recruitment of progenitor cell populations or by replication of mature cells. [source] Effects of hepatic blood inflow occlusion on liver regeneration following partial hepatectomy in an experimental model of cirrhosisBRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 11 2000X. -Y. Background Hepatic blood inflow occlusion during hepatectomy may influence postoperative liver regeneration. The aim of this study was to investigate the influence of hepatic blood inflow occlusion on liver regeneration following partial hepatectomy in thioacetamide-induced cirrhotic rats. Methods Forty-three cirrhotic Wistar,Furth rats were randomly assigned to three groups. Rats in group 1 underwent 64 per cent hepatectomy alone, those in group 2 were subjected to 15 min hepatic blood inflow occlusion followed by 64 per cent hepatectomy, and animals in group 3 were subjected to 30 min inflow occlusion followed by 64 per cent hepatectomy. Liver function, 5-bromo-2,-deoxyuridine (BrdU) labelling index and percentage of initial liver weight on days 1, 2 and 7 posthepatectomy were assessed. Results Rats in groups 1 and 2 had a significantly higher serum albumin level and a markedly lower alanine aminotransferase level than animals in group 3 on day 1 posthepatectomy (P < 0·05). There was no significant difference in the serum level of total bilirubin of the three groups on days 1, 2 and 7. The BrdU labelling index was significantly higher in groups 1 and 2 than in group 3 animals on day 1 posthepatectomy (P < 0·01 and P < 0·05 respectively). Percentages of initial liver weight were similar in groups 1, 2 and 3 on days 1, 2 and 7 after hepatectomy. Conclusion Hepatic blood inflow occlusion for up to 30 min suppressed DNA synthesis and hepatocyte proliferation at an early posthepatectomy stage and consequently delayed recovery of liver function in cirrhotic rats. However, it did not affect restoration of liver mass or survival after 64 per cent hepatectomy. © 2000 British Journal of Surgery Society Ltd [source] Nonregenerative stimulation of hepatocyte proliferation in the rat: Variable effects in relation to spontaneous liver growth; a possible link with metabolic inductionCELL PROLIFERATION, Issue 5 2000C. Nadal Three procedures were used to stimulate hepatocyte proliferation in the rat without reducing liver mass, resulting in a supplementary growth which differs from the regenerative growth observed after loss of liver mass by hepatectomy or toxic necrosis. They were: (a) the ingestion of cyproterone, a cytochrome P450 inducing drug (b) the injection of an irritant which provokes glycogenesis and synthesis of acute-phase proteins (c) the injection of albumin-bound bilirubin leading to elimination of glucuronated bilirubin in bile. This ensuing supplementary growth was studied in the rat under several conditions of hepatic proliferation: 1In normal adult rats, in which hepatocyte proliferation is very low, the effect on proliferation was either weak or undetectable. 2In suckling rats, with a rapid body and liver growth, all the stimulants provoked a synchronized wave of proliferation with a steep increase of the percentage of S-phase hepatocytes from 4.5% in controls to 15,30% in treated rats. This increase was followed by a compensatory period of low proliferation during which a treatment with a second stimulant was much less effective. 3In 2/3 hepatectomized adult rats, the proliferation induced by cyproterone was higher than the spontaneous regenerative proliferation alone and additional to it during all of the regenerative process. The proliferation induced by acute inflammation was competitive with the synchronous spontaneous proliferation during the early period of synchronized proliferation following surgery, suggesting that both are similar acute responses. Differently, during the late period of lower and unsynchronized regenerative proliferation, the proliferation provoked by acute inflammation was additional to the spontaneous one. A stimulation of proliferation by injection of the albumin-bilirubin complex was observed during the late period after 2/3 hepatectomy. The highest level of stimulation occurred when the liver growth and the hepatocyte proliferation were already high. This suggests that these stimulants are not complete mitogenic stimuli and need cofactors which are present during the spontaneous growth or, alternatively, that the effect of stimulants is opposed by an inhibitory mechanism present in the adult rat. [source] The diagnostic value of on-site cytopathological evaluation and cell block preparation in fine-needle aspiration cytology of liver massesCYTOPATHOLOGY, Issue 5 2006K. Ceyhan Objective:, The aims of this study were to evaluate the typing accuracy of conventional smear (CS), cell block (CB) preparations and combined use of both procedures (CS + CB) for the diagnosis of hepatic malignancies and to determine whether immediate on-site cytopathological evaluation improves the diagnostic yield of liver fine-needle aspiration cytology (FNAC). Methods:, Ultrasound-guided FNABs were performed on 323 consecutive cases with liver masses between December 2002 and December 2004. Histologically and/or clinically correlated 167 cases were included in the study. Preliminary FNAB results, results of CS, CB, and combined use of CS and CB were compared regarding diagnostic sensitivity, specificity, and accuracy for the diagnosis of malignancy. Subtyping accuracies of different methods were also compared. Results:, The sensitivity of on-site cytopathological examination and CS were both 92.8%. The sensitivity of CS + CB was slightly better than that of CB (93.5% versus 84.8%). Specificity of all procedures was achieved 100%. Diagnostic accuracy of on-site cytopathological evaluation, CS, CB, and CS + CB were 93.9%, 93.9%, 87.2%, and 94.5%, respectively. A specific subtype diagnosis of malignant tumours could be rendered accurately on the basis of preliminary diagnosis in 71%, CS in 75.4%, CB in 78.3% and combined approach in 92% of cases. In terms of typing accuracy, 87.5% of HCCs, 93.2% of adenocarcinomas, 92.3% of neuroendocrine carcinomas, 100% of lymphomas and 100% of other malignant tumours were correctly subclassified in the final cytopathological diagnosis. The agreement between preliminary diagnosis and final cytopathological diagnosis was 77.2%. Conclusion:, With use of on-site cytopathological evaluation and combined use of CS and CB, the diagnostic accuracy of liver tumours approaches 100% and also significantly improve diagnostic and subtyping accuracy of liver malignancies. [source] Peripheral endothelial cells are not reliable in differentiating primary benign and malignant hepatocellular lesions in fine needle aspirates of the liverCYTOPATHOLOGY, Issue 3 2002GORDON H. YU The distinction of hepatocellular carcinoma (HCC) from benign lesions of the liver in fine needle aspiration (FNA) specimens can be problematic. In an attempt to separate well-differentiated HCC from benign hepatocellular lesions, the presence of tissue fragments displaying peripheral endothelial cells (PE) has been proposed in a previous study as a useful feature in favour of malignancy. In this study, we evaluated slides from 59 cases of liver masses undergoing FNA (19 HCC, 40 benign) and evaluated them for the presence of tissue fragments containing PE. We found that 90% of cases of HCC contained tissue fragments in which PE were either focally present or abundant. However, 68% of cases containing only benign hepatocytes also contained tissue fragments in which PE were at least focally present. In addition, it appears that within the group of benign lesions, the presence of PE was related to the overall cellularity of the specimen rather than the specific nature of the lesion. Thus, the presence of PE in tissue fragments does not, in isolation, appear to be a useful morphological feature for the separation of benign and malignant hepatocellular lesions in FNA material. [source] Radiologically guided percutaneous fine-needle aspiration biopsy of the liver: Retrospective study of 119 cases evaluating diagnostic effectiveness and clinical complicationsDIAGNOSTIC CYTOPATHOLOGY, Issue 5 2002Ph.D., Ziwen Guo M.D. Abstract We reviewed 119 percutaneous, radiologically guided fine-needle aspirations (FNA) from 114 patients with liver masses to evaluate diagnostic effectiveness and complications of this procedure. Satisfactory material was obtained in 118 cases (99%), of which 78 were diagnosed as positive (66%), three suspicious (2%), five atypical (4%), and 32 (27%) as negative for malignancy. Compared to surgical biopsy (48 cases) and clinical data, the sensitivity and specificity of FNA for malignancy was 95.1% and 100%, respectively, yielding a positive predictive value of 100% and a negative predictive value of 88.8%. Four cytology cases (3.4%) were false-negatives (FN); all were interpretive errors. Four FN surgical biopsies (8.3%) were sampling errors. Minor complications occurred in three cases (2.5%). We conclude that FNA is safe and effective for determining the malignant potential of liver masses and should be the procedure of choice. Our experience suggests that having a pathologist present in the radiology suite provides optimal patient care. Diagn. Cytopathol. 2002;26:283,289. © 2002 Wiley-Liss, Inc. [source] Detection and differential diagnosis of hepatic masses using pulse inversion harmonic imaging during the liver-specific late phase of contrast enhancement with levovistJOURNAL OF CLINICAL ULTRASOUND, Issue 4 2002Cem Yücel MD Abstract Purpose The purpose of this study was to investigate whether late-phase pulse inversion harmonic imaging (PIHI) increases conspicuity in hepatic masses, helps to differentiate benign from malignant lesions, and demonstrates a greater number of and smaller metastatic lesions than do conventional (fundamental) sonography and helical CT. Methods Thirty patients (17 women and 13 men; age range, 35,77 years; mean age, 54 years) with known or suspected liver masses were evaluated using both fundamental sonography and contrast-enhanced PIHI during the liver-specific late phase of Levovist. The patients also underwent contrast-enhanced triphasic helical CT examinations within 1 week after sonography. In 4 of the patients, gadolinium-enhanced MRI was also performed as a part of their clinical work-up. Results The increase in the lesions' conspicuity on PIHI compared with fundamental sonography was significantly greater in malignant lesions than in benign lesions (p< 0.001). An echogenic rim was observed on PIHI in 8 (53%) of 15 malignant lesions. The mean number of metastatic lesions visualized on PIHI (5.5 ± 5.3) was significantly higher than the mean number visualized on fundamental sonography (2.5 ± 2.1, p < 0.05). Although lesions as small as 3 mm were observed on PIHI, the mean sizes of the smallest lesions demonstrated using fundamental sonography, PIHI, and helical CT were not significantly different. Conclusions Late-phase PIHI is a useful technique for characterizing hepatic lesions and demonstrating both a greater number of and smaller metastases. It may help to differentiate benign from malignant liver masses and may obviate unnecessary and expensive further imaging. © 2002 Wiley Periodicals, Inc. J Clin Ultrasound 30:203,212, 2002; Published online in Wiley InterScience (www.interscience. wiley.com). DOI: 10.1002/jcu.10053 [source] | ||||||||||||||||||||||||||||