Spontaneous renal lymphosarcoma in a juvenile cynomolgus monkey (Macaca fascicularis)

Spontaneous lymphosarcoma, likely of renal origin, was diagnosed in a naive, juvenile, male cynomolgus monkey (Macaca fascicularis). Histologically, renal architecture was effaced by dense infiltrating sheets of plump cells with indistinct borders and scant amphophilic cytoplasm. Mitoses were uncommon. Similar neoplastic infiltrates were also present in the right renal cortex, one adrenal medulla, the prostate, seminal vesicles, myocardium, and the pulmonary interstitium. Serological tests were negative for infection with Simian Immunodeficiency Virus (SIV), Simian T-Lymphotropic Virus-1 (STLV-1), and Simian Retrovirus-5.     

Immunohistology of gastrointestinal carcinoid tumors

DAKO quick staining kits were used to immunostainings for Epithelial Membrane Antigen (EMA) Neuron Specific Enolase (NSE) and S-100 protein (S-100) in 18 carcinoid tumors of the gastrointestinal tract classified according to Soga and Tazawa. EMA was always absent in carcinoid tumors, being at the same time present within glandular epithelium. 88% of cases showed positive immunostaining for NSE. S-100 immunostaining showed immunopositive stellate cells present within the tumor especially within type A carcinoids. In addition in one carcinoid tumor thick, strongly S-100 positive bundles were noticed at the periphery of nests of tumor cells. Combined immunohistochemical and ultrastructural studies are needed to elucidate interrelation of neoplastic and neural elements within carcinoid tumorsa.     

Qualitative and quantitative analysis of erythrocyte surface membrane sialyl residues using affinity cytochemistry with special reference to diabetic patients

The adenocarcinoma produced by transplantation into nude mice of a neoplastic human salivary intercalated duct cell line was treated with 0.1 ml of minimal essential medium (MEM) containing dibutyryl cyclic AMP (dB-cAMP) at a final concentration of 1 mM daily for 28 days and examined morphologically and immunohistochemically. The dB-cAMP treatment resulted in a marked suppression of tumor growth. In addition, tumor nests with a myoepithelial cell phenotype characterized by the presence of microfilament systems reactive with antimyosin and anti-S-100 protein sera were often observed in the treated tumors, but not in untreated controls. These findings lead us to suggest that neoplastic intercalated duct cells can be induced to differentiate into myoepithelial cells and that levels of cAMP within the cells may regulate this cytodifferentiation.     

Gene expression and immunohistochemical localization of basic fibroblast growth factor in renal cell carcinoma.

Renal cell carcinoma is known as a neoplastic condition of renal tubular cells and usually shows a hypervascular tumor in angiographic examination. We examined the presence of basic fibroblast growth factor (bFGF) in human renal cell carcinoma. To determine if alterations in bFGF gene expression are present in human renal cell carcinoma, paired samples of normal and neoplastic renal tissue from 6 patients were analyzed for bFGF mRNA content by Northern blot hybridization. In 4 out of 6 patients, tumor tissue expressed bFGF mRNA 2 to 4 times greater than corresponding normal tissue. Two patients showed minimal elevation of tumor bFGF mRNA. The localization of bFGF in the renal cell carcinoma tissue was also examined using immunohistochemical staining, and it was found that bFGF was positively stained at the nuclei of tumor cells and the cell surface. These results suggest that increased expression of bFGF may be associated with neoplastic growth in renal tubular epithelial cells and neovascularization.     

Primary hepatic neuroendocrine carcinoma in a baboon (Papio sp.)

Background  Primary neuroendocrine carcinomas of the liver have rarely been reported in humans and domestic animals, but not in non-human primates.
Methods  We describe the morphologic and immunohistochemical features of a primary hepatic neuroendocrine carcinoma found in a 29-year-old female baboon.
Results and conclusions  The neoplasm was characterized by multiple solid nodules that were multifocally distributed in the liver. Metastases were not observed. Histologically, the neoplasm was composed of cords and nests of epithelial cells arranged in a neuroendocrine pattern, occasionally forming glandular and rosette-like structures. On immunohistochemical evaluation, the neoplastic cells were immunopositive for pancytokeratin, chromogranin A, neuron-specific endolase, and synaptophysin and were negative for vimentin, S100 protein, glucagon, and insulin.     

Squamous cell carcinoma in rudd Scardinius erythrophthalmus: histopathology, ultrastructure, and transmission

The histopathology and ultrastructure of a skin neoplasm in rudd Scardinius erythrophthalmus (L.) are described and the neoplasm is diagnosed as squamous cell carcinoma. In the early stage, tumour cells appear singly or in clusters close to the epidermis; then tumour cells are seen in the dermis as epithelial pearls/nests, cords or sheets with central keratin; and with further development of the neoplasm, tumour cells appear as large sheets and masses, enclosing extensive keratinous formations and foci of necrotic cells, infiltrating deeper into the dermis and penetrating the muscle layers. Increasing vascularity and inflammation are associated with all stages of progression. In some cases metastases are observed in the viscera. Electron microscopic examination shows that the neoplastic cells are joined by desmosomes; the cytoplasm contains abundant mitochondria and rough endoplasmic reticulum. The neoplasm was successfully transmitted experimentally to healthy rudd when tumour cells were inoculated subcutaneously. Eight of 19 surviving test fish developed tumour growth at the site of tumour cell injection and/or in a corresponding site on the opposite of the body. One of these 8 fish, which developed a neoplasm, also showed a microscopic internal tumour in the viscera. One of the 19 test fish showed a microscopic tumour in the spleen, even though no skin tumour was visible in this fish. No tumours were found in control fish. In contrast, intraperitoneal injection of tumour cells into healthy rudd did not result in transmission of the neoplasm.     

Histological markers of solid cell nests of the thyroid. With some emphasis on their expression in thyroid ultimobranchial-related tumors

It was recently demonstrated that C cells, mucosubstances, and the intermediate filament epidermal keratin are present in solid cell nests (SCN) of the thyroid. The reliability and usefulness of these markers in detecting these ultimobranchial nests have, so far, not been comparatively investigated. In the light of this, a study for the presence of these tracers in SCN at different stages of postnatal life was undertaken. The existence of carcinoembryonic antigen (CEA) in this gut-derived tissue was also searched for. Epidermal keratin was present in the epidermoid-like cells from all SCN studied; calcitonin-immunoreactive C cells and mucosubstances did not always occur. These findings reveal that this cytokeratin would remain as a potential marker to detect and trace back the ultimobranchial tissue component of the thyroid in earlier stages of development. The presence of CEA in practically all SCN surveyed would further support the view that they originate in the gut. This antigen would also be of great value for histological identification of these nests. The usefulness of these markers for the interpretation of the histogenesis of some ultimobranchial-related thyroid neoplastic growths, specifically the medullary and mucoepidermoid carcinomas, is briefly discussed.     

Uterine müllerian adenosarcoma with histiocytic (xanthomatous) mesenchymal component.

We present an endometrial Müllerian adenosarcoma in which the sarcomatous component showed prominent nests of foamy cells that accounted for 50% of the neoplastic mesenchyma. Such foamy cells showed occasional cytological atypias and immunohistochemical features of histiocytic (macrophagic differentiation in the absence of changes that could substantiate the presence of an inflammatory infiltration of foamy histiocytes. These facts suggest histiocytic differentiation from neoplastic mesenchymal cells. Such differentiation has been reported in association with malignant mixed mesodermal tumor, but not in Müllerian adenosarcoma.     

A comparative study in twelve mammalian species of volume densities, volumes, and numerical densities of selected testis components, emphasizing those related to the Sertoli cell

Morphometric studies were performed on 12 mammalian species (degu, dog, guinea pig, hamster, human, monkey, mouse, opossum, rabbit, rat, stallion, and woodchuck) to determine volume density percentage (Vv%), volume (V), and numerical density (Nv) of seminiferous tubule components, especially those related to the Sertoli cell, and to make species comparisons. For most species, measurements were taken both from stages where elongate spermatids were deeply embedded within the Sertoli cell and from stages near sperm release where elongate spermatids were in shallow crypts within the Sertoli cell. Montages, prepared from electron micrographs, were used to determine Vv% of Sertoli cell components in seminiferous tubules. Excluding the tubular lumen, the Sertoli cell occupied from a high of 43.1% (woodchuck) to a low of 14.0% (mouse) of the tubular epithelium. There was a strong negative correlation (r = -0.83; P less than 0.005) of volume occupancy of Sertoli cells with sperm production. Nuclear volume, as determined by serial reconstruction using serial thick sections, ranged from a high of 848.4 microns 3 (opossum) to a low of 273.8 microns 3 (degu). There was no correlation (r = 0.02) of nuclear volume with volume occupancy (Vv%) in the tubule. Sertoli cell volume was determined by point-counting morphometry at the electron-microscope level as the product of the nuclear size and points determined over the entire cell divided by points over the nucleus. Sertoli cell V ranged from 2,035.3 microns 3 (degu) to 7,011.6 microns 3 (opossum) and was highly correlated (r = 0.85; P less than 0.001) with nuclear size. However, there was no significant correlation between the Sertoli cell size (V) and volume occupancy (Vv%; r = 0.13) or sperm production (r = -0.21). Stereological estimates of the numerical density (Nv) of Sertoli cells ranged from a high of 101.9 x 10(6) (monkey) to a low of 24.9 x 10(6) (rabbit) cells per cm3 of testicular tissue. There was no correlation of numerical density of Sertoli cells with sperm production (r = 0.002). A negative correlation was, however, observed between the numerical density of the Sertoli cells and the Sertoli cell size (r = -0.79; P less than 0.002). Data from the present study are compared with those previously published. This is the first study to compare Sertoli cell morphological measurements using unbiased sampling techniques. Morphometric data are provided which will serve as a basis for other morphometric studies.     

Neoplastic odontogenic epithelial cells express bone sialoprotein

Bone sialoprotein (BSP) is synthesized and secreted by bone-, dentine- and cementum-forming cells and has been implicated in de novo bone formation and mineralization. In this study, we used histological sections of odontogenic neoplasms and performed immunohi stochemical and in situ hybridization analyses. In ameloblastoma, BSP mRNA signals were seen in the neoplastic epithelial cells forming nests, strips and islands. BSP deposition was also seen in the stellate reticulum of the tumour masses revealed by immunohistochemistry using human BSP antibodies. In calcifying epithelial odontogenic tumour, the calcified masses demonstrated positive immunoreactivity to the human BSP antibodies, and the hybridization signals for BSP were located in the cells near the calcified particles. In the calcifying odontogenic cyst, strong BSP signals were seen in cells surrounding the characteristic nests of ghost cells, which often calcify subsequently. BSP protein was also found in these cells by immunohistochemistry. The active expression of BSP in the epithelial elements of the odontogenic tumours of adult patients suggests the activation of this matrix protein gene in the neoplastic process, and that BSP may play an important role in tumour formation and differentiation with respect to pathological calcification. © Chapman & Hall     

Spontaneous peritoneal malignant mesothelioma in a geriatric japanese macaque (Macaca fuscata).

A 28.5-year-old female Japanese macaque (Macaca fuscata) was euthanatized because of abdominal distension due to severe ascites. Nodular lesions of varying sizes up to 5 mm in diameter were distributed diffusely on the surface of the omentum, mesentery and parietal peritoneum. No neoplastic masses were detected in any visceral organ. The nodules were composed of proliferation of mono- or multi-layered epithelial-like cells occasionally showing papillary growth and sheets of small round or polygonal cells. Signet ring-like cells and tubular structures were occasionally present. Neoplastic cells were strongly positive to cytokeratin, and occasionally to vimentin. Based on gross and histopathological findings, this tumor was diagnosed as an epithelial type of peritoneal malignant mesothelioma, the first reported case in the non-human primates.     

Preparation of rhinovirus antisera in the South American hystricomorph rodent, Octodon degus (38507).

Rhinovirus antisera have been prepared for rhinoviruses (RV) 7,9,26,32,67 and 87 in guinea pigs and in degus. Titers achieved were either similar in the 2 animals (RV7) somewhat higher in the degu (RV9 and RV32) or clearly higher in the degu (RV26, RV67 and RV87). Specificity of the antisera was similar in both animals. In special instances where it is difficult to prepare high-titered rhinovirus antisera in the guinea pig, the degu offers an attractive alternative source.     

Lymphosarcoma in an infant northern fur seal (Callorhinus ursinus)

An infant northern fur seal (Callhorinus ursinus) died in a rookery on St. Paul Island, Pribilof Islands, Alaska. Grossly, slight enlargement of the mesenteric lymph nodes was seen. Microscopically, a lymphosarcoma composed of sheets of monomorphic lymphoid cells in sections of lymph node and tonsil was seen. Electron microscopy of formalin-fixed tissues revealed several structures that were possible of viral origin in the cytoplasm of the neoplastic cells.     

Histomoniasis and reticuloendotheliosis in a wild turkey (Meleagris gallopavo) in North Carolina

A moribund wild turkey (Meleagris gallopavo) died shortly after it was discovered in Martin County, North Carolina (USA). The 4.3-kg female turkey appeared in good condition with no visible external lesions or evidence of injury. There were 2- to 5-mm yellow-white plaques on the mucosal surfaces of the oral cavity and mid-esophagus. The liver had large, multifocal, irregular pale areas on cut and uncut surfaces. The spleen contained multifocal, pale, hard, nodules. Microscopic changes in the liver consisted of large multifocal coalescing areas of necrosis. Occasional spherical 10 to 15 microns in diameter organisms consistent with Histomonas meleagridis were present in the necrotic areas. Viable hepatic parenchyma contained multifocal infiltrations of numerous mononuclear cells interpreted as neoplastic cells resembling lymphoblasts and plasma cells. Similar neoplastic cell infiltrates, consistent with the lymphoproliferative disease reticuloendotheliosis, were present in spleen, lung, and esophageal and oral mucosa. Reticuloendotheliosis virus, subtype 2, was isolated from samples of liver and spleen.     

Cytologic profile of rhabdoid tumor of the kidney. A report of 3 cases

BACKGROUND: Malignant rhabdoid tumor of the kidney (MRTK) is a rare malignant neoplasm that usually presents as an abdominal mass. The histogenesis is uncertain, and cases outside the kidney have been reported. An association with separate primary tumors of primitive neuroepithelial origin occurring in the midline of the posterior or middle cranial fossa has been reported in approximately 15% of cases. CASES: Three patients, a 7-month-old girl and two boys, aged of 6 and 2 months of age, underwent fine needle aspiration biopsy (FNAB) for the diagnosis of renal masses. In 2 cases the smears revealed round to polygonal cells, singly or arranged in irregularly shaped clusters. The neoplastic cells did not differ much in shape and exhibited clear, empty nuclei with prominent nucleoli; the cytoplasm was abundant and sometimes eosinophilic. In the remaining case the aforementioned characteristics of the nuclei and cytoplasm were not as prominent, and sheets of fibrovascular stroma, with attached neoplastic cells, were seen. Diagnosis of MRTK was suspected in every case based upon morphology and immunocytochemistry; the diagnosis was histologically confirmed in the surgical specimens. CONCLUSION: MRTK may pose diagnostic problems due to its broad morphologic spectrum. Distinction from Wilms' tumor and clear cell sarcoma of the kidney is essential for therapeutic proposes. The results obtained in the FNAB study of these 3 cases demonstrate that diagnosis of MRTK may be proposed from fine needle aspiration smears using conventional methods together with ancillary ones (immunocytochemistry and electron microscopy).     

Histological and histochemical studies on the distribution of a few enzymes in the neoplastic liver of Uroloncha malabarica (Linnaeus)

The present work describes histological and histochemical observations made on the neoplastic liver of Indian silver bills, Uroloncha malabarica. The histology of neoplastic tissue as well as liver has been discussed. Further, a few enzymes like alkaline phosphatase, acid phosphatase, 5-nucleotides and non-specific esterase have been localized in the diseased liver. The occurrence of lymphocytoma caused a marked change in the localization of the enzymes. Sometimes total inhibition of the enzyme was encountered. Damaged sinusoid cells and bile canaliculi of the neoplasm as well as liver lobules show no reaction for alkaline phosphatase. However, its counterpart, acid phosphatase, exhibits intense activity in both neoplastic tissue and liver cells. Aggregates of neoplastic tissue give moderate 5-nucleotidase reaction while it gives poor activity in hepatic tissue of the diseased liver. Parenchymatous cells are able to give some activity for the non-specific esterase while it is very dull in the neoplastic tissue.     

Primary perivascular epithelioid cell tumor of the liver not related to hepatic ligaments: hepatic PEComa as an emerging entity

Primary perivascular epithelioid cell tumor (PEComa) of the liver is a very rare example of an emerging family of hepatic PEC tumors. Only few cases have been described so far. We report the case of a large but benign hepatic PEComa in a 53-year-old man without signs of tuberous sclerosis. In contrast to recently described PEC-derived liver tumors in children and young adults, this neoplasm was not related to the hepatic ligaments but had developed deeply within the liver substance. The neoplastic cells displayed the complete phenotype typical for PEComas, i.e. reactivity for several melanoma markers and for smooth muscle actin. The unique relationship of myoid tumor cells to the adventitia of blood vessels prompted us, in comparison with published findings obtained with angiomyolipomas, to comment on the possible origin of the still enigmatic perivascular epithelioid cells.     

Fine needle aspiration biopsy cytology of metastatic renal cell carcinoma

Sixteen cases of metastatic renal cell carcinoma diagnosed by fine needle aspiration biopsy were reviewed. Polygonal malignant epithelial cells present in sheets with loose or strong cellular cohesiveness and granular, vacuolated or filmy cytoplasm were the characteristic findings of this type of tumor.     

Spinal metastasis of a thyroglobulin-rich Hürthle cell carcinoma detected by fine needle aspiration. Light and electron microscopic study of an unusual case

A prospective diagnosis of metastatic thyroid carcinoma was made on an aspirate of a spinal mass. While the cellular component of the aspirate was compatible with a renal or hepatic neoplasm, the recognition of colloid on air-dried smears defined the cells as Hürthle cells. Biopsy of the spinal tumor and subsequent thyroidectomy revealed a Hürthle cell carcinoma. Whereas the primary tumor showed typical Hürthle cell architecture, with solid tumor nests and microfollicle formation, the metastasis contained areas of macrofollicle formation with abundant colloid production and strong immunocytochemical reactivity for thyroglobulin. This change of histologic pattern from the primary tumor to the metastasis has not been previously reported in Hürthle cell lesions. The unusual light microscopic and ultrastructural aspects of this tumor are discussed.     

Ineffectiveness of plastic mesh for protecting artificial freshwater turtle nests from red fox (Vulpes vulpes) predation

Invasive mammalian predators are efficient at driving native animal declines. The red fox (Vulpes vulpes) kills millions of endemic reptiles in Australia each year. In areas of south-eastern Australia, the eastern long-necked turtle (Chelodina longicollis) and Murray River turtle (Emydura macquarii) have declined by more than 50%. High rates of nest predation by foxes limit the recruitment of young turtles in these populations, but previous methods of fox control have been ineffective at protecting turtle nests. Here, we tested the effectiveness of plastic mesh for protecting artificial turtle nests from predation by foxes, in the mid-Murray catchment, Victoria. We also tested whether protecting a large number of artificial nests in a given area encourages foxes to give up foraging following predictions from giving-up density theory. We made a series of plots, each containing 32 artificial turtle nests. In each plot, we covered a percentage (0%, 25%, 50%, 81% or 100%) of the nests with either 1 or 2 sheets of plastic mesh. We used remote cameras to photograph and identify any predator that attacked nests in the plots. The cameras also allowed us to estimate the amount of time a fox was visible on each plot, as a metric of how much effort foxes expended on protected nests. Nest survival rate was not increased by either 1 or 2 sheets of mesh, and increasing the number of protected nests on a plot did not reveal a giving-up density (GUD) value for fox foraging behaviour. Our study demonstrates that plastic mesh is not effective for protecting artificial turtle nests from foxes in this region.