Hepatic Lymph Research Articles

Pathological and Immunohistochemical Study of the Liver and Hepatic Lymph Nodes in Goats Infected with One or More Doses ofFasciola hepatica

Lesions produced byFasciola hepaticain the liver, gall-bladder and hepatic lymph nodes (HLNs) of four groups of five goats are described; in addition, the distribution of CD3+T lymphocytes and IgG-lambda light chain-bearing cells was analysed in the hepatic lesions and HLNs. One group of goats received a single oral dose of metacercariae, but the other four groups received four or five doses at different intervals over a period of 11 weeks. Animals that survived were killed 53–55 weeks after the first infective dose. Goats were more susceptible to multiple doses than to a single dose, even when the total number of metacercariae was the same. This greater susceptibility was manifested by the occurrence of deaths and the severity of hepatic lesions. CD3+lymphocytes were sparse in the infiltrate surrounding the acute migratory tracts, suggesting inhibition of the local cell-mediated immune response. Goats with numerous hepatic calcareous granulomas showed the most severe hepatic damage, including marked cirrhosis, with a striking infiltrate of CD3+T lymphocytes and lambda IgG+plasma cells, replacing extensive areas of hepatic parenchyma, in which hypertrophy of the smooth endoplasmic reticulum of hepatocytes was evident. These findings were observed mainly in the goats given more than one infective dose.

IFN gamma and IL-10 production by hepatic lymph node and peripheral blood lymphocytes in Fasciola hepatica infected sheep.

The present study was designed to determine whether IFN gamma and IL-10 were secreted by peripheral blood mononuclear cells (PBMC) and hepatic lymph node mononuclear cells (HLNMC) from 17 Fasciola hepatica infected sheep after in vitro stimulation by Fasciola hepatica excretory-secretory products (FhESP) during the first six weeks of two different infections. The IFN gamma concentration in mononuclear cells (MC) culture supernatants was determined by sandwich ELISA. The presence of IL-10 in MC culture supernatants was determined by the capacity of these to inhibit, with or without monoclonal antibodies to IL-10, the NO production of recombinant bovine IFN gamma (rBoIFN gamma) activated monocytes. FhESP-stimulated PBMC and HLNMC produced IFN gamma in culture supernatants from DPI 7 (day post-infestation 7) to DPI 14. Culture supernatants of PBMC stimulated with FhESP first induced an increase in the NO production of rBoIFN gamma activated monocytes. After 2 or 3 weeks of infection, MC culture supernatant reduced the NO production of rBoIFN gamma activated monocytes. From DPI 35, anti-IL-10 antibodies addition restored or enhanced NO production. During sheep fasciolosis, IFN gamma production increased only until the first two weeks post infection. IL-10 could be secreted throughout the first six weeks of infection and could inhibit monocytes from DPI 35.

Observation of thoracic duct morphology in portal hypertension by endoscopic ultrasound

Background:Thoracic duct dilation has been demonstrated in portal hypertension and hepatic cirrhosis by lymphangiography and laparotomy and at autopsy. It is thought to be secondary to increased hepatic lymph flow and has been described in the absence of ascites or esophageal varices. The aim of the present study was to observe thoracic duct morphology by endoscopic ultrasound in various subsets of patients with portal hypertension and hepatic cirrhosis and also to validate existing radiologic/surgical data. Methods:The thoracic duct of 33 patients with cirrhosis and portal hypertension was studied by endoscopic ultrasound. Patients were divided into four groups: 1, patients with ascites and esophageal varices; 2, esophageal varices without ascites; 3, without esophageal varices or ascites; 4, extrahepatic portal hypertension due to pancreatic malignancy. The thoracic duct diameter was also measured in 14 control subjects (group 5). Results:When the thoracic duct diameter for the five groups was compared with analysis of variance, significance was p < 0.0001; by pairwise comparison, group 1 differed from the other four groups ( p < 0.05). Thoracic duct dilation (5.61 mm) was seen in group 1 patients, whereas no dilation was present in groups 2 through 4. Additionally, thoracic duct diameter in 33 portal hypertensive and/or cirrhotic patients was significantly different from that in the 14 control subjects ( p = 0.003). Conclusion:The thoracic duct can be reliably identified by EUS in patients with hepatic cirrhosis and portal hypertension. Dilation of the duct is seen only in patients with hepatic cirrhosis, ascites, and esophageal varices. No thoracic duct dilation is present in extrahepatic portal hypertension. Contrary to existing radiologic/surgical data, thoracic duct dilation is not seen in all patients with hepatic cirrhosis and portal hypertension signifying advanced disease. A dilated thoracic duct by endoscopic ultrasound should be considered yet another sign of portal hypertension. (Gastrointest Endosc 1998;48:588-92.)

Identification and precursor frequency analysis of a common T cell epitope motif in mitochondrial autoantigens in primary biliary cirrhosis.

The immunodominant antimitochondrial antibody response in patients with primary biliary cirrhosis (PBC) is directed against the E2 component of the pyruvate dehydrogenase complex (PDC-E2). Based on our earlier observations regarding peripheral blood mononuclear cell (PBMC) T cell epitopes, we reasoned that a comparative analysis of the precursor frequencies of PDC-E2 163-176-specific T cells isolated from PBMC, regional hepatic lymph nodes, and from the liver of PBC patients would provide insight regarding the role of T cells in PBC. Results showed a disease-specific 100-150-fold increase in the precursor frequency of PDC-E2 163-176-specific T cells in the hilar lymph nodes and liver when compared with PBMC from PBC patients. Interestingly, autoreactive T cells and autoantibodies from PBC patients both recognize the same dominant epitope. In addition, we demonstrated cross-reactivity of PDC-E2 peptide 163-176-specific T cell clones with PDC-E2 peptide 36-49 and OGDC-E2 peptide 100-113 thereby identifying a common T cell epitope "motif" ExETDK. The peptide 163-176-specific T cell clones also reacted with purified native PDC-E2, suggesting that this epitope is not a cryptic determinant. These data provide evidence for a major role for PDC-E2 peptide 163-176 and/or peptides bearing a similar motif in the pathogenesis of PBC.

Maturation of rat dendritic cells during intrahepatic translocation evaluated using monoclonal antibodies and electron microscopy.

Specific populations of hepatic sinusoidal cells were stained with monoclonal antibodies that recognize monocytes/macrophages (ED1), tissue macrophages (Kupffer cells) (ED2), MHC class II (Ia) antigen (MRC OX6), and dendritic cells/gamma,delta T-cells (MRC OX62) and analyzed by light and electron microscopy. The majority of ED1(+) and/or ED2(+) cells were localized to the hepatic parenchyma, whereas OX6(+) and/or OX62(+) cells were more densely distributed within Glisson's sheath than in the hepatic parenchyma. Double-immunoperoxidase staining of normal liver for ED1, ED2, and OX6 identified dendritic cells (DC) of two different phenotypes, ED1(+)ED2(-)OX6(+) and ED1(-)ED2(-)OX6(+). DC can be classified into three different types based on ultrastructural characteristics. The first type (type I) is characterized by one or more long cytoplasmic processes and a well-developed lysosomal system. The second type (type II) has an inconspicuous lysosomal system, abundant hyaloplasm, and characteristic short cytoplasmic processes. The third type (type I-II) has cytologic features intermediate between those of type I and type II DC. At the electron-microscopic level, these three cell types are found in the sinusoidal lumen, whereas the majority of type II DC are located in the space of Disse and Glisson's sheath. Furthermore, some OX6-labeled elongated DC appeared to traverse the lumen of sinusoids through endothelial pores to enter the space of Disse. One hour after intravenous injection of latex particles (0.81 micrometer in diameter), numerous latex-laden dendritic cells (ED1(+)OX6(+), type I and type I-II) were detected in the lumen of hepatic sinusoids, but not in the space of Disse or Glisson's sheath. These findings suggest that normal rat liver contains resident dendritic cells which downregulate phagocytic activity and mature into potent accessory cells during migration from the portal vein toward the central vein. These DC then traverse the sinusoidal lumen to the hepatic lymph system via the space of Disse.

Immunohistochemical study of the local immune response to Fasciola hepatica in primarily and secondarily infected goats

The distribution of CD2, CD4, CD8, γ/δ T-lymphocytes, B-cells and IgG lambda-light chain (λ-IgG) containing cells were analysed in the inflammatory infiltrate associated to hepatic lesions and gallbladder (HL), and in hepatic lymph nodes (HLN) of goats primarily and secondarily infected with Fasciola hepatica. In the HL, CD2 and CD8 T-cells were more numerous ( p=0.01) in secondarily rather than in primarily infected goats, whereas CD4 T-lymphocytes were less numerous than CD8 and showed no significant change in both groups. The ratio CD4/CD8 was 0.66 and 0.39 for primarily and secondarily infected goats, respectively. In contrast, in the HLN, CD4 were more numerous than CD8 T-cells, the ratio CD4/CD8 was 2.0 in control, 1.5 and 1.3 in primary and secondary infections, respectively. γ/δ T-lymphocytes were scarce in the HL and moderate in the HLN of both primarily and secondarily infected animals. B-cells (IgM +, λ-IgG + or CD79 +) varied from scarce or moderate in the HL to abundant in the HLN, where CD79 +-cells were mainly located in lymphoid follicles and IgM and IgG in plasma-cells of the medullary cords, suggesting an intense local humoral immune response. However, this response did not prevent the hepatic damage in secondarily infected goats, in which hepatic lesions were more severe than in primarily infected ones.

Cholangiographic features in the diagnosis and management of obstructive icteric type hepatocellular carcinoma.

In 11 years and 3 months, 2037 patients with HCC were seen and 48 patients (2.4%) were diagnosed to have obstructive icteric type HCC. Five patients were terminally ill and were not investigated further. Forty three patients were initially investigated by endoscopic retrograde cholangiography (ERC) or percutaneous transhepatic cholangiogram (PTC) and classified as having obstructive icteric type 1, 2, or 3 HCC based on the cholangiographic findings. The obstruction in type 1 HCC was due to intraluminal tumour casts and/or tumour fragments obstructing the hepatic ductal confluence or common bile duct, while intraluminal blood clots, from haemobilia, filling the biliary tree was the cause in type 2 HCC. The pathology in type 3 HCC was extraluminal obstruction by extensive tumour encasement of the intra–hepatic biliary ductal system and/or extrinsic compression of the hepatic and common bile ducts by tumour(s) and/or malignant lymph nodes. At the initial ERC/PTC, 10 patients (5 resected, 50%) had obstructive icteric type 1 and 23 patients (0 resected) had obstructive icteric type 3 HCC. Of the 10 patients initially classified according to cholangiography to have obstructive icteric type 2 HCC, subsequent investigations revealed that 6 patients had type 1 HCC (4 resectable, 67%) and 4 patients had type 3 HCC (0 resectable). The classification of the obstructive icteric type HCC into types 1, 2, and 3, based on the initial cholangiographic appearances has simplified and rationalized our management strategy for this condition.

Changes in lymph vessels and portal veins in the portal tract of patients with idiopathic portal hypertension: A morphometric study

Little is known about the effects of the pathological process associated with idiopathic portal hypertension (IPH) on hepatic lymph vessels or lymph flow. We used morphometric analysis to examine IPH-associated changes in lymph vessels and branches of the portal vein, with use of immunohistochemical staining for alpha smooth muscle actin. We also quantitated these changes using an image analysis system. The study was conducted with use of liver wedge biopsy material from 10 patients with advanced IPH and 10 control samples from patients with gastric carcinoma without liver disease. The number of lymph vessels, identified by a lack of smooth muscle layer in the wall, and the ratio of the total area of these vessels to that of the portal tract were higher in IPH samples than in the control samples, but the ratio of the area of a single lymph vessel to that of the portal tract in IPH samples was not different from control samples. The number of portal vein branches, characterized by hypertrophy of the smooth muscle layer in IPH samples was not different from control samples. The ratio of the total area of these branches to that of the portal tract, and the ratio of a single portal vein branch to that of the portal tract, were lower in IPH samples than in the control samples. Our results suggest that these morphometric changes in IPH may be associated with a reduction in portal blood flow and increased lymph flow, and that the latter may in turn reduce the high portal vein pressure in idiopathic portal hypertension.

Concentrations of sulfadoxine and trimethoprim in plasma, lymph fluids and some tissues 24 h after intramuscular administration to angora goats

Summary This study was carried out to determine the concentrations of sulfadoxine and trimethoprim in plasma, lymph, and some tissues in goats after administration of a single recommended therapeutic dose. Five healthy, adult Angora goats were used. The drug combination, containing 200 mg sulfadoxine and 40 mg trimethoprim per millilitre, was given as a single IM injection at the recommended dose level, 15 mg/kg body weight for sulfadoxine and 3 mg/kg body weight for trimethoprim. The goats were slaughtered 24 hours after drug administration and samples were taken from liver, bone marrow, pelvic limb muscles, hepatic, thoracic duct, and the pelvic limb lymph fluids for analysis of drug concentrations by HPLC. The concentrations of trimethoprim in bone marrow, liver, pelvic limb muscles, hepatic lymph, the pelvic limb lymph, and thoracic duct lymph were found to be 6, 5, 4, 2, 5 and 15 times higher than those of plasma, respectively. Although the sulfadoxine concentrations in bone marrow, pelvic limb muscles, and liver were 2, 3 and 2 times higher than the plasm concentrations, respectively, the sulfadoxine concentrations in hepatic lymph, the pelvic limb lymph, and thoracic duct lymph were lower than those of plasma. The results show that the trimethoprim concentrations in lymph fluids were quite similar to those in tissues. However, the sulfadoxine concentrations in lymph fluids were different in each tissue.

Estudos histológico, histoquímico e ultra-estrutural de fígados e linfonodos de bovinos com presença de macrófagos espumosos ("foam cells")

Foram examinadas amostras de fígado, rins, baço e linfonodos hepáticos, mesentéricos, retro-mandibulares, pré-escapulares e mediastínicos de 12 lotes em um total de 120 animais, envolvendo diferentes faixas etárias, todos oriundos do Estado de Mato Grosso. Os animais haviam sido mantidos em pastos onde Brachiaria decumbens e Brachiaria brizantha eram as forrageiras predominantes. Macroscopicamente o fígado desses animais mostrava coloração amarelada, mais evidente após 24 horas de fixação em formol a 10%. Nos linfonodos hepáticos e mesentéricos foram evidenciadas, na superfície de corte, estriações esbranquiçadas de forma radiada na cortical e medular com pequenas áreas brancas nodulares multifocais principalmente na medular. Em muitos casos, associado com essas áreas foram vistos focos de aspecto hemorrágico. Microscopicamente foram encontradas, no fígado, linfonodos hepáticos e mesentéricos, células com citoplasma espumoso, muitas das quais multinucleadas. Nos linfonodos hepáticos e mesentéricos estes infiltrados estavam associados a áreas de necrose e hemorragia. No fígado, as células de citoplasma espumoso estavam presentes em todo parênquima, de forma irregular, geralmente formando nódulos ao redor da veia centrolobular. Estas células não se coravam pelo ácido periódico de Schiff (PAS) e apenas fracamente na coloração de gordura pelo Oil Red O. Na ultra-estrutura as células de citoplasma espumoso apresentavam fendas, parcial ou totalmente delimitadas por membrana, que representam a imagem negativa de cristais, presentes também no citoplasma dos hepatócitos.

Primary vascular neoplasms of lymph nodes in the dog.

Primary vascular neoplasms of lymph nodes are rare, and appear not to have previously been reported in domestic animals. This report describes hemangiomas and a lymphangioma in lymph nodes of aged Beagle dogs. Eight hemangiomas (4.8%) and one lymphangioma were present in 165 examined popliteal lymph nodes, and one hemangioma occurred in a hepatic lymph node. The hemangiomas were cavernous and benign.

Interleukin (IL)-2, IL-4, and tumor necrosis factor-alpha responses during Entamoeba histolytica liver abscess development in gerbils.

To determine cytokine production patterns during hepatic amebiasis, gerbils were infected with Entamoeba histolytica in the liver. Then spleen and hepatic lymph node cell proliferation and interleukin (IL)-2 (a Th1 marker), IL-4 (a Th2 marker), and tumor necrosis factor-alpha (TNF-alpha) production in response to concanavalin A and amebic antigen in vitro were quantified. Early abscess development (day 5 after inoculation) coincided with IL-2, IL-4, and low TNF-alpha production and strong lymphoproliferative responses, whereas suppression of IL production and lymphoproliferation occurred during acute disease (day 20). Proliferative responses and IL-2 production increased at days 30 and 60 after inoculation, but IL-4 levels remained low. Animals drug-treated at day 20 after inoculation demonstrated high IL-2 and low IL-4 production and resistance to reinfection. While acute hepatic amebiasis in gerbils is accompanied by transient immunosuppression, late infection and resistance to reinfection are associated with IL-2 production but low IL-4 and TNF-alpha production (Th-1-like response).

A novel migration pathway for rat dendritic cells from the blood: hepatic sinusoids-lymph translocation.

The migration pathways for dendritic cells (DC) from the blood are not yet completely resolved. In our previous study, a selective recruitment of DC progenitors from the blood to the liver was suggested. To clarify the role of the hepatic sinusoids in the migration of blood DC, relatively immature DC and mature DC were isolated from hepatic and intestinal lymph, and intravenously transferred to allogeneic hosts. It was then possible to detect small numbers of DC within secondary lymphoid tissues either by immunostaining for donor type major histocompatibility complex class I antigen or, at much higher sensitivity, for bromodeoxyuridine incorporated by proliferating cells (mainly T lymphocytes), which responded to the alloantigen presented by the administered DC. The intravenously injected DC accumulated in the paracortex of regional lymph nodes of the liver via a lymph-borne pathway. Intravenously injected fluorochrome-labeled syngeneic DC behaved similarly. In contrast, very few DC were found in spleen sections and were hardly detectable in other lymph nodes or in other tissues. An in situ cell binding assay revealed a significant and selective binding of DC to Kupffer cells in liver cryosections. It is concluded that rat DC can undergo a blood-lymph translocation via the hepatic sinusoids, but not via the high endothelial venules of lymph nodes. Hence the hepatic sinusoids may act as a biological concentrator of blood DC into the regional hepatic nodes. Kupffer cells may play an important role in this mechanism.

CYSTIC ADENOCARCINOMA POSITIONED IN THE PORTA HEPATIS-REPORT OF A CASE-

A 64-year-old woman who was pointed out impaired hepatic function at a medical checkup was seen at the hospital. Abdominal ultrasonography and CT revealed a multilocular cystic tumor 3.5cm in size involving solid component at the porta hepatis. With ERC the right hepatic duct did not visualized, and dilated right intrahepatic bile duct and compressed and extended left hepatic duct were shown. Abdominal angiography revealed a compressed and extended caudate lobe branch. From these imaging findings, a most probable diagnosis of cystic adenocarcinoma positioned in the porta hepatis was made, and the patient was operated on. Operative procedures included percutaneous transhepatic portal embolization followed by extended excision of the right lobe, excision of the bile duct, and left Roux-Y hepatocholangiojejunostomy. The tumor had enrolled the right hepatic duct, and the major part of the tumor existed in the bile duct extramurally covering from the confluence of the right and left hepatic ducts to right intrahepatic first branch, though a part of it protruded into the right hepatic ductal space. Histopathologically it was well differentiated papillary adenocarcinoma limiting in the cyst. Cystic adenocarcinomas positioned in the porta hepatis are so rare that four cases in addition to this case have been reported so far. Since the right and left hepatic ducts are adjacent to the hepatic parenchyma and connect to the intrahepatic bile duct, the primary site can not be determined in not a few cases. In the treatment of the disease, hepatectomy with a sufficient distance from the tumor, excision of the hepatic duct and lymph nodes dissection are neceessary.

The liver sinusoids as a specialized site for blood-lymph translocation of rat dendritic cells.

The fate as well as the significance of blood dendritic cells (DC) is not yet completely resolved. Some may migrate to the splenic white pulp1 and other immature DC may reach the epithelial tissues to become resident DC. When particulates are injected intravenously, relatively immature particle-laden DC appear in the peripheral lymph draining the liver2. The results suggest that the rat DC lineage may be selectively recruited to the liver after intravenous injection of particulates and that they subsequently translocate from the liver vasculature to the hepatic lymph. The present study was performed to demonstrate the migration pathway of blood DC and the existence of specialized vasculature for DC, the liver sinusoids.KeywordsLiver PerfusateImmature Dendritic CellMature Dendritic CellLiver SinusoidBlood Dendritic CellThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Imaging of small cell carcinoma of the male urogenital tract

Five cases of small cell carcinoma (three of the prostate and two of the bladder) are described to illustrate the unusual behaviour of these tumours. Cerebral, hepatic and bulky lymph node spread with large volume local disease occurred. The role the radiologist may play in these diseases is discussed.

Anatomic variation of extrahepatic biliary tree structures: importance in treatment planning for radiation therapy.

To demonstrate the variable location of biliary tree components and to assess two treatment planning rules of thumb used for locating porta hepatic nodes for radiation therapy. The distance of the common hepatic duct bifurcation and duodenal papilla from adjacent vertebral bodies was measured on 34 cholangiograms, and their relationships to particular vertebral body levels were recorded. Adequacy of treatment volume to encompass porta hepatic lymph nodes was evaluated in 30 of these cholangiograms by constructing radiation portals according to the two rules of thumb. Location of the common hepatic duct bifurcation and duodenal papilla varied widely. The treatment portal encompassed 13% (four of 30) of cases when the first rule of thumb was used and 80% (24 of 30) of cases when the second rule of thumb was used. The wide variability of location of extrahepatic biliary tree structures suggests the need for individualized treatment planning so that sensitive and dose-limiting healthy tissues can be optimally excluded from radiation treatment portals. Computed tomography and other imaging modalities enable precise location of biliary tree components for radiation treatment planning.

Local immune response to experimental Fasciola hepatica infection in sheep.

Macrophages, eosinophils, neutrophils and lymphocyte subpopulations (OvCD5+, OvCD4+, OvCD8+, OvWC1+ and lg+) were identified in sections of hepatic tissue and hepatic lymph nodes from sheep experimentally infected with F. hepatica and necropsied 14, 28, 42 or 56 days post infection. The migratory tunnels produced by juvenile flukes appeared as local areas of necrosis surrounded by infiltrating inflammatory cells, particularly numerous macrophages, eosinophils and OvCD4+ lymphocytes n addition, B lymphocyte proliferation was observed in hepatic lymph nodes and in hepatic portal tracts. Only three juvenile flukes were identified in the sections. They where partially in contact with healthy tissue and partially with neutrophils, macrophages and eosinophils; they were covered by IgM Host-parasite interactions resulting from immune response regulation by helper T lymphocytes and from immune evasion by the parasite are discussed.

Thoracic Duct-Cutaneous Fistula in a Patient With Cirrhosis of the Liver: Successful Treatment With a Transjugular Intrahepatic Portosystemic Shunt

Patients with cirrhosis of the liver have increased hepatic and gastrointestinal lymph flow that may contribute to the formation of ascites and pleural effusions. Increased lymph flow, which is due to postsinusoidal portal hypertension, causes a high rate of flow through the thoracic duct. Because of the high flow rates, disrupted lymphatic vessels in patients with cirrhosis of the liver may fail to close, a situation that results in chylous ascites, pleural effusions, or chylous fistulas. Chylous fistulas deplete proteins, fluid, and lymphocytes and thus lead to volume depletion and coagulopathy. Herein we describe an unusual case in which a high-output traumatic thoracic duct-cutaneous fistula developed in a patient with cirrhosis and led to volume depletion and coagulopathy. Correction of the portal hypertension with placement of a transjugular intrahepatic portosystemic shunt led to closure of the fistula and normalization of accompanying metabolic abnormalities.

A retrospective study of pancreatic tumors in slaughter cattle.

Sixteen primary pancreatic tumors were found in a retrospective study of bovine pancreatic lesions detected in slaughtered cattle. Eleven islet cell tumors and three pancreatic exocrine carcinomas were identified based on light microscopy and immunohistochemistry. Nine of 11 islet cell tumors were classified as malignant. Metastatic sites included iliac, mediastinal, hepatic, and mesenteric lymph nodes, peritoneum, mesentery, and liver. Six cows with multiple islet cell tumors also had pheochromocytomas. All 11 islet cell tumors had positive immunoreactivity to insulin and somatostatin. Three tumors also contained cells immunoreactive for glucagon and two tumors contained pancreatic polypeptide immunoreactive cells. Immunoreactivity of tumor cells in metastatic sites was similar to their respective primary tumors. All exocrine pancreatic carcinomas metastasized widely and were immunonegative for insulin, somatostatin, glucagon, and pancreatic polypeptide. No mixed endocrine-exocrine tumors were identified. None of the endocrine or exocrine tumors contained amyloid. Additional primary tumors of the bovine pancreas included one neurofibroma and one neurofibrosarcoma. Additional cases with lesions of the bovine pancreas included nodular hyperplasia in 15 cows, exocrine acinar atrophy and fibrosis in four cows (two of which also had pancreatic lithiasis), pancreatitis in one cow, peripancreatic fibrosis in two cows, pancreatic steatosis in one animal, and pancreatic hemorrhages in one cow.