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We describe the clinical and pathological features of a brain collision tumour consisting of a fibrous meningioma and an anaplastic oligoastrocytoma in a 14-year-old male neutered French Bulldog. Computed tomography of the brain revealed a poorly defined, intra-axial lesion affecting the left frontal lobe. Following euthanasia, histological examination showed an anaplastic oligoastrocytoma invading the brain parenchyma and an adjacent fibrous meningioma. As synchronous intracranial tumours are rare in animals, the aims of this report are to describe the clinical, imaging and histopathological features of an intracranial collision tumour in a dog and highlight the importance of a complete histopathological study despite the imaging findings., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

A 13-year-old female miniature dachshund was presented with a centrally-located sublingual mass in the rostral mandibular region. The focally ulcerated growth completely covered the left (305) and right (405) premolar teeth and partially covered the right canine teeth (404). A punch biopsy sample revealed neoplastic proliferation of odontogenic epithelium arranged in irregular cords with frequent comedo-like necrosis. Following the initial diagnosis of ameloblastic carcinoma, a bilateral rostral hemimandibulectomy was performed. Although the detailed examination of the resected mass was consistent with the initial diagnosis, it also contained birefringent congophilic, amelogenin-labelled amyloid deposits similar to an amyloid-producing odontogenic tumour (APOT) in 30-40% of the mass, in continuity with the ameloblastic carcinoma. All neoplastic cells had diffuse moderate expression of cytokeratin (CK) AE1/AE3 and CK5, diffuse mild expression of CK14 and multifocal moderate expression of CK19. Because the APOT-like growth in the mass was histologically benign, the tumour was diagnosed as an ameloblastic carcinoma arising from an APOT., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

A 10-year-old entire male French bulldog was presented following clusters of generalized tonic-clonic epileptic seizures. Neurolocalization was consistent with a lesion in the left forebrain. Magnetic resonance imaging of the brain revealed a large, ill-defined, intra-axial, space-occupying lesion at the level of the left temporal and parietal lobes, causing marked compression of the adjacent parenchyma. Computed tomography of the thorax and abdomen was consistent with disseminated metastatic disease. The dog was humanely destroyed and subjected to necropsy examination. Histological examination of the brain revealed a metastasis of prostatic carcinoma within an anaplastic oligodendroglioma in the left forebrain. To the author's knowledge, this is the first report describing clinical, imaging and histopathological features of an intracranial tumour-to-tumour metastasis in the brain of a dog., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Peripheral nerve sheath tumours (PNSTs) are neoplastic growths derived from Schwann cells, perineural cells or both. Malignant PNSTs (MPNSTs) are uncommon in domestic animals. This report describes the concomitant occurrence of PNSTs in a 10-year-old female cocker spaniel with a clinical history of respiratory impairment. Grossly, there was a large infiltrative mass in the caudal lobe of the right lung; smaller nodules were observed in the other lobes of the right lung. Furthermore, a small encapsulated cutaneous nodule was observed on the left hindlimb. Histopathology of the pulmonary tumours revealed the proliferation of pleomorphic spindle-shaped cells with moderate mitotic index arranged in interwoven bundles and concentric Antoni A and Antoni B patterns; invasion of the adjacent pulmonary tissue was observed. The cutaneous nodule consisted of neoplastic mesenchymal cells in interwoven bundles with concentric whorls, but without the marked anisokaryosis, binucleation and infiltrative growth seen in the pulmonary tumour. Immunohistochemistry revealed that both tumours were immunoreactive for vimentin, glial fibrillary acidic protein and S100 protein, but were negative for factor VIII. These findings are indicative of a MPNST in the lung with a concomitant benign PNST in the limb. This case represents the first report of a primary MPNST in the lung of a dog. This neoplastic growth should be included in the differential diagnosis of primary malignant pulmonary tumours of dogs., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Brain tumours in cattle are uncommon and the spontaneous development of primary brain tumours of different histological types is rare in both man and animals. In man, multiple concurrent primary tumours of different types are occasionally described. We report the rare simultaneous occurrence of two different primary brain tumours, gliosarcoma and choroid plexus carcinoma, diagnosed by microscopical and immunofluorescence evaluation in an 8-year-old cow with a 2-month history of neurological disease. Gliosarcoma is a rare variant of glioblastoma multiforme, characterized by the presence of malignant glial cells and mesenchymal tissue. This tumour has not been reported previously in animals., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

A 7-year-old, male cocker spaniel was presented with a gingival proliferative lesion in the rostral maxilla and enlargement of the regional lymph node. Morphological and immunohistochemical analysis revealed a collision tumour composed of two malignant populations, epithelial and melanocytic, with metastasis of the neoplastic melanocytes to the regional lymph node. The epithelial component consisted of trabeculae and islands of well-differentiated squamous epithelium immunoreactive to cytokeratins. The melanocytic component had a varying degree of pigmentation of polygonal and spindle-shaped cells, growing in nests or densely packed aggregates and immunolabelled with S100, melanoma-associated antigen (melan A), neuron-specific enolase and vimentin antibodies. Protein markers involved in tumorigenesis or cell proliferation (i.e. COX-2, p53, c-kit and Ki67), were overexpressed by the neoplastic cells. To the authors' knowledge, this is the first description of an oral collision tumour involving malignant melanoma and squamous cell carcinoma in the dog., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

The Scottish wildcat (Felis silvestris) is an iconic and endangered subpopulation of the European wildcat (F. silvestris silvestris). There is much research devoted to the ecology, genetics and conservation of this animal, but little published information on pathology and disease. The investigation and reporting of such information is vital to furthering understanding of the effects of hybridization, a factor that is crucial if we are to secure a future for the Scottish wildcat. This report describes the clinical presentation, gross post-mortem and histological findings in an elderly Scottish wildcat hybrid with concurrent transitional meningioma and ceruminous gland adenocarcinoma., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

We describe a case of pancreatic adenocarcinoma and Brunner's gland adenoma in an 18-year-old male Siberian tiger (Panthera tigris altaica) from the Ljubljana Zoo. The tiger was humanely destroyed due to weakness and progressive weight loss. Necropsy examination revealed a large, grey, predominantly necrotic mass replacing the major part of the pancreatic body. Microscopically, the mass was unencapsulated, poorly demarcated, highly cellular and composed of highly pleomorphic, cuboidal to tall columnar cells with basal, round or oval, moderately anisokaryotic nuclei with prominent nucleoli and moderate to large amounts of eosinophilic cytoplasm. The tumour was diagnosed as pancreatic tubular adenocarcinoma with infiltration into the duodenum and mesentery. There were tumour emboli in mesenteric blood vessels and hepatic metastases. The non-affected part of the pancreas exhibited severe chronic pancreatitis. In addition, one firm white neoplastic nodule was observed in the duodenal wall. The nodule was set in the tunica muscularis and was unencapsulated, well demarcated and highly cellular, and consisted of a closely packed layer of normal Brunner's glands and a centrally positioned group of irregularly branched tubules with small amounts of debris in the lumen. The neoplastic nodule was diagnosed as Brunner's gland adenoma. The present case is, to the best of our knowledge, the first report of concurrent pancreatic adenocarcinoma and Brunner's gland adenoma, most probably induced by chronic pancreatitis, either in man or animals., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

A 25-year-old, female rhesus macaque (Macaca mulatta) presented with a history of weight loss despite a normal appetite and supportive care. The animal was humanely destroyed due to poor prognosis. Post-mortem examination revealed a focally extensive, firm, white annular constriction at the ileocaecal junction and an incidental finding of a pale white nodule approximately 0.8 cm in diameter in the left renal pelvis. Based on the microscopical findings, ileocaecal adenocarcinoma and renal pelvis transitional cell carcinoma (TCC) were diagnosed. The use of cytokeratin (CK)-7 and -20 and uroplakin III as potential renal TCC markers was evaluated. The neoplastic cells were labelled intensely with antibodies to uroplakin III, but not to CK-7 or -20. Spontaneous intestinal adenocarcinoma has been documented in the rhesus macaque, but concurrent renal pelvis TCC is highly unusual., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Southern sea otters (Enhydra lutris nereis) are threatened marine mammals that belong to the family Mustelidae and are native to the coast of Central California. Neoplasia is reported infrequently in sea otters. An adult female free-ranging southern sea otter was found alive at Pebble Beach, Monterey County, California, on January 1st, 1994 and died soon after capture. The carcass was submitted to the US Geological Survey - National Wildlife Health Center for necropsy examination. Grossly, a mass with rubbery texture was firmly attached to the left maxillary region of the skull and the nasopharynx was occluded by soft neoplastic tissue. Post-mortem skull radiographs showed an oval, smoothly marginated mineralized opaque mass centered on the left maxilla, extending from the canine tooth to caudal to the molar and replacing portions of the zygomatic arch and palatine and temporal bones. The majority of the mass protruded laterally from the maxilla and was characterized by central homogeneous mineral opacity. Microscopically, the mass was characterized by fully differentiated lamellar non-osteonal bone that expanded beyond the margins of the adjacent normal osteonal bone. Sections of the nasopharyngeal mass were comprised of moderately pleomorphic cells with bony stroma. Gross, microscopical and radiological findings were compatible with maxillary osteosarcoma with concurrent osteoma., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Fifty-three tumours were diagnosed in samples originating from 167 different black-tailed prairie dogs (Cynomys ludovicianus) submitted to Northwest ZooPath (NZP) between 1996 and 2009. Three prairie dogs had more than one type of neoplasm. Thirty-two of the 50 prairie dogs were from zoological parks in the USA; 17 were owned privately and one was from a wildlife centre. Ages ranged from 2-9 years (median age 5.6 years) for 41 animals in which age was known. Thirty-nine (73.6%) of the tumours were classified as malignant and 14 (26.4%) were benign. Common sites for tumours were the liver, the alimentary tract and the haemolymphoid and integumentary systems. Hepatocellular carcinoma, hepatocellular adenoma, lymphoid malignancies and elodontoma were diagnosed most commonly., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

A 15-year-old Limousin-cross cow was presented for examination with neurological signs and serum biochemical changes consistent with liver disease. Necropsy revealed enlargement of the liver with multifocal firm, depressed, pale, circumscribed lesions throughout the parenchyma. Within the gallbladder there were exophytic and villiform mucosal masses. Microscopically, hepatic structure was displaced by neoplastic cells forming trabeculae, nests and rosettes. There was transmural infiltration of the gallbladder by similar cells. The histological pattern of growth of the neoplastic cells, the presence of silver-stained cytoplasmic granules within these cells and the immunohistochemical demonstration of chromogranin A supported the diagnosis of neuroendocrine carcinoma. Bovine liver and gallbladder neuroendocrine carcinomas are rare and this is the first detailed documentation of the disease in the United Kingdom.

In cattle, bracken fern chronic toxicity is characterized by the presence of multiple tumours in the bladder (bovine enzootic haematuria). From October 1999 to March 2003, 433 urinary bladders with macroscopical lesions were collected in the slaughterhouse of São Miguel Island (Azores, Portugal), an endemic area where Pteridium aquilinum infestation in pastures is high. Bladder lesions were divided into three main categories (inflammatory lesions, non-neoplastic epithelial abnormalities and tumours) and described in detail. In some cases, neoplastic growth was confined to a single site, but in most cases multiple tumours developed within the same bladder. Epithelial tumours alone were present in 51.2% of the affected bladders, mesenchymal tumours alone in 17.4%, and both epithelial and mesenchymal tumours in the remaining 31.4%. The large number of tumours examined (870) revealed new categories not yet included in other veterinary classification systems, namely, inverted papilloma, papillary neoplasm of apparent low malignant potential, and haemangioendothelioma.

Multicentric malignant Schwannoma in a crossbred cow is described. Multiple and solitary nodules of varying sizes were seen to be distributed throughout the body of the animal, mainly along the peripheral nerves supplying the muscles of the thoracic and abdominal regions and the skin. Multiple nodules were also observed in the hilus of the liver. The mediastinal lymph nodes were replaced by a large solitary tumorous mass. Multiple neoplastic linear cords with small nodules were observed on the pericardium. Histologically, the nodules showed mainly densely packed, spindle-shaped cells arranged in short interwoven bundles and whorls (Antoni type A pattern). Stellate, spindle-shaped and round or oval tumour cells proliferated haphazardly within the loose texture of a collagenous matrix (Antoni type B pattern). Immunohistochemically, in both Antoni type A and type B areas, neoplastic cells reacted with antibodies against S-100 protein. Based on the metastasis of the tumour to the lymph nodes and on histology, the neoplasm was diagnosed as a multicentric malignant Schwannoma.

Chronic ingestion of bracken fern (Pteridium spp.) by cattle produces upper alimentary tract and urinary bladder tumours causing a syndrome called bovine enzootic haematuria (BEH). Previous studies demonstrated ptaquiloside-DNA adducts and mutations in the h-ras gene in ileal epithelial cells of bracken fern-fed calves. Systematic inspection of the bladder mucosa of grazing cattle (n=126) from bracken-fern areas was carried out in a slaughterhouse. Of the 126 slaughterhouse cattle, 46 showed macroscopical lesions of the bladder. These bladders, together with six others known to have BEH, were examined histopathologically and by H-ras immunohistochemistry. Thirteen affected bladders were also examined by H-ras molecular analysis to detect mutations. Macroscopical and histological study of urinary bladder lesions found at the slaughterhouse revealed chronic cystitis (34.1%) and tumours (2.4%). There was significantly increased immunohistochemical expression of H-ras (P<0.05) in chronic cystitis (H-ras=53.24%) and bladder tumours (H-ras=63.60%) as compared with normal urinary bladders (H-ras=4.32%). A silent mutation (D38D) was detected in one animal with a mixed bladder tumour. The prevalence of urinary bladder lesions (chronic cystitis and tumours) obtained at the slaughterhouse was higher than expected. This study demonstrates that close inspection of urinary bladders of adult grazing cows is necessary to prevent possible human exposure to bracken-fern carcinogens. The absence of mutations in the codons of h-ras studied did not exclude the presence of polymorphisms in other regions of the gene (promoter or regulation sequences) or in other genes (belonging or not to the ras family) that significantly affect the H-ras protein.

Ten sheep naturally affected with enzootic nasal adenocarcinoma (ENA), a disease associated with ovine enzootic nasal tumour virus (ENTV-1), were found also to be infected with jaagsiekte sheep retrovirus (JSRV), the causal agent of ovine pulmonary adenocarcinoma (OPA). Only one of the sheep showed OPA lung lesions. The animals belonged to 10 flocks located in a geographical area in which OPA is frequently seen. ENTV-1 was found in all the ENA tumours but only occasionally in extra-tumoral sites, confirming the results of a previous study. In contrast, JSRV had a disseminated tissue distribution, similar to that previously reported for animals infected with JSRV. However, the occurrence of JSRV in lymphoid tissues was clearly greater than in sheep infected with JSRV but with no lesions of ENA. The data suggested a synergistic relationship between ENTV-1 and JSRV, resulting in increased proliferation of JSRV.

Severe hypergastrinaemia in the dog is considered a strong indicator for a gastrin-producing pancreatic islet cell tumour. In human medicine, gastrinomas are described as enteropancreatic neuroendocrine tumours that cause the Zollinger-Ellison syndrome. However, in contrast to the supposed origin of canine gastrinomas in pancreatic islets, gastrinomas in human beings arise predominantly in the duodenum and gastric antrum, and are often a component of the syndrome of multiple endocrine neoplasia type I. This report is of a canine case of multiple endocrine neoplasms, consisting of a pancreatic islet cell somatostatinoma, and a gastrinoma in the mesenteric lymph nodes and liver. From the literature and the authors' findings, it is concluded that the clinical diagnosis of hypergastrinaemia is not pathognomonic for a gastrin-producing islet cell tumour. Furthermore, the presence of an islet cell tumour in the face of hypergastrinaemia does not warrant a diagnosis of an islet cell gastrinoma. Immunohistochemistry is necessary to confirm the diagnosis of a pancreatic islet cell gastrinoma.

Two primary tumours, squamous cell carcinoma of the tongue and multiple bronchioloalveolar carcinomas, were diagnosed in a Virginia opossum (Didelphis virginiana). Two oral masses were located in the right ventrolateral surface of the tongue, near the frenulum, and the lungs contained multiple, widely distributed, nodular masses. Microscopically, the oral masses were composed of invasive cords of pleomorphic, polyhedral cells, typical of squamous cells. The multiple pulmonary masses consisted of non-ciliated, cuboidal, columnar, or occasionally polyhedral cells arranged in an alveolar pattern with multifocal areas of necrosis. This is the first report of spontaneous oropharyngeal squamous cell carcinoma in the Virginia opossum. However, multiple pulmonary adenomas have been reported previously in this species, the lesions being similar to those in sheep pulmonary adenomatosis (jaagsiekte). In the present study, immunohistochemical examination of the pulmonary tumours with a rabbit polyclonal antiserum to jaagsiekte retroviral capsid protein proved negative., (Copyright Harcourt Publishers Ltd.)

The development of spontaneous multiple tumours is a rare event in domestic rabbits. The diagnosis of a cutaneous basal cell tumour and the successive development of simultaneous bilateral testicular tumours with dissimilar histology (a seminoma and an interstitial cell tumour) are described in a vasectomized, crossbred dwarf rabbit, aged 6 years. Two cases of basalioma associated with uterine adenocarcinoma have been previously described in rabbits. A similar association between basal cell neoplasia and development of tumours (e.g., testicular and breast cancer) at cutaneous and non-cutaneous sites has been reported in man., (Copyright 1999 W.B. Saunders Company Ltd.)

In a necropsy series at the German Primate Centre, 63 of 1132 tree shrews were found to have tumours. The youngest affected animal was < 6 months old, but the incidence of tumours increased strikingly beyond 2 years of age; of 17 animals aged > 8 years, no less than 14 (82.4%) were affected. The sites of neoplasia were the genital system (22 cases), haematopoietic system (18 cases of malignant lymphoma, many involving the digestive tract), lungs (14 cases), integument (five cases), digestive tract (three cases other than those with malignant lymphoma) and urinary bladder (one case).

A hepatic malignant tumour composed of both hepatocellular and cholangiocellular elements was studied histologically, immunohistochemically and electron microscopically in an 18-year-old Thoroughbred mare. Bile canaliculi and alpha-fetoprotein were useful in identifying the hepatocellular element, and mucin and keratin were good markers of biliary differentiation. The simultaneous presence of bile canaliculi and mucin-producing cells in most of the neoplastic lesions suggested that this tumour arose from a stem cell with capacity to differentiate into hepatocytes and biliary epithelium.

The microscopical and immunohistochemical features of a rare cutaneous leiomyoma in a cat are described. The principal characteristics of this tumour were multiple bundles of smooth muscle, either discrete or conjoined, with numerous collagen fibres between the muscle cells, and osteoid metaplasia. The tumour was designated a piloleiomyoma as it was considered to have arisen from the arrector pili muscles.

Abdominal malignant mesothelioma was found in a 17-year-old, spayed female Japanese domestic cat with mast cell leukaemia. The mesothelioma was mainly located at the periphery of the pancreas, spleen and stomach, and showed metastases to the lung, an anterior mediastinal lymph node and lymph ducts in the tracheal mucosa. Micro-circulatory defects caused by the mast cell leukaemia may have been partly responsible for the distant metastases.

Spontaneous altered hepatocellular foci (AHF) of basophilic type were observed in adult male cotton rats. The histological features of these foci were similar to those observed in Fischer 344 rats. However, an immunohistochemical technique with antibody to glutathione S-transferase placental form (GST-P) failed to stain these foci. Also normal bile ducts were not immunoreactive for GST-P. The presence of a gall bladder and of non-GST-P immunoreactive liver foci and bile ducts suggests that these cotton rats are phylogenetically closer to mice than rats.

Two cases of C cell hyperplasia and one case of C cell carcinoma of the thyroid glands were bilaterally recognized in 11 sheep with experimentally-induced lymphosarcoma. The serum calcium concentration in the C cell carcinoma case was slightly increased above the normal concentration of around 9 mg per dl. Bilateral C cell hyperplasia also developed in the thyroid lobes of the C cell carcinoma case. Immunohistochemically, hyperplastic C cells and tumour cells were positive for calcitonin, calcitonin gene-related peptide, chromogranin A and neurone-specific enolase. No amyloid deposition nor multiple endocrine neoplasia was demonstrated in any of the cases. Ultrastructurally, many secretory granules were observed in the cytoplasm of neoplastic cells constituting the C cell carcinoma and in the hyperplastic C cells.

In this report the morphological and immunohistochemical features with respect to intermediate filament proteins and the neuroendocrine nature of bilateral neuroblastomas possibly originating from the adrenal medulla in a goat kid are presented. Histologically, the tumours were composed of small, round, blue cells organized in highly cellular nests and sheets separated by fibrovascular septa. Isolated cells mimicking the morphological features of neurones were observed in both tumours. Ultrastructurally, dense-core neurosecretory granules, about 100 nm in diameter, and irregularly organized neurotubular networks were seen. The small tumour cells were only labelled by vimentin, while the neurone-like cells were labelled by both neurone-specific enolase and synaptophysin. The lack of staining of the tumour cells by the neurofilament proteins antiserum, which was also observed in a human neuroblastoma (used as positive control) has been previously reported and is probably the result of the tissue processing and/or the poor differentiation stage of the tumours. The vimentin labelling of tumour cells could be explained by the poor differentiation stage of the tumours, since vimentin is the only intermediate filament protein in presumptive neuroblasts, being replaced by neurofilament proteins in later stages of neurogenesis.

In a blue fox farm about 300 of 400 weanling pups were affected with diarrhoea and prolapse of the rectum. About 40 pups died in an emaciated state after a few days of disease. Eight pups were submitted for examination. Pathological findings were restricted to the caecum, proximal colon and rectum, with occasional extension to the ileum. Affected areas revealed a thick and rigid intestinal wall, a narrow lumen and a thickened, wrinkled and sometimes ulcerated mucosa. Histologically, the mucosa showed long tortuous crypts outlined by a high pseudostratified epithelium which lacked goblet cells. Epithelial cells revealed increased basophilia, and mitoses were seen along the entire crypt length and in the surface epithelium. Silver impregnation showed curved organisms in the apical cytoplasm of the altered epithelial cells. Penetration of the muscularis mucosa by the altered epithelial cells was frequent. The avidin-biotin-immunoperoxidase complex (ABC) technique revealed positive organisms in the apical cytoplasm of altered epithelial cells, when rabbit antisera against different biotypes and serotypes of Campylobacter jejuni and Campylobacter coli were used. Antisera against Campylobacter sputorum subsp. muscosalis and Campylobacter hyointestinalis were negative.

Scanning electron microscopy of adenomatous intestinal tissue in the blue fox revealed an irregular surface topography of the colon with increased diameter of the crypt openings and prominent ridge formations between crypts. The ileum showed villous atrophy and fusion. Microvilli were short and irregular. Small ulcerations of intestinal mucosa were seen. Freeze-fracture revealed curved intracellular organisms in the altered epithelial cells. Transmission electron microscopy showed features associated with immaturity and high protein synthesis. Filamentous extensions from the basolateral plasma membrane of altered epithelial cells sometimes penetrated the basal lamina. The cytoplasm contained numerous polyribosomes, nuclei had many indentations and large and irregular nucleoli. Intracellular bacteria, with morphology corresponding to Campylobacter spp. were found in the apical epithelial cytoplasm. No host-cell-derived membrane was seen to surround the bacteria.

A retrospective study of abstracted data representing 1.1 million hospital examinations of dogs at veterinary university teaching facilities identified 77 with bile duct carcinoma. Using the hospital population, based on patient years at risk, as the expected frequency of particular zoographic characteristics, there was a suggestion of a familial (breed) predisposition in Labrador retrievers and limited evidence of a sex differential. Because mongrel dogs displayed about the same frequency of bile duct cancer as all breeds combined, other causal factors, besides genetics, are implied. A possible association was detected between canine cholangiocarcinoma and host infection by canine hookworms and/or whipworms. Human infection from hookworms (Necator americanus) and whipworms (Trichuris trichiura) is common in the southern rural areas of the U.S.A. (e.g. Appalachia), and tropical and sub-tropical countries of Africa, Central and South America, where there have been unexplained high rates reported for human biliary cancer. It is possible that the presence of these blood-letting nematodes, like a number of other parasites (ascarids, flukes and protozoa), may be related to the occurrence of human cholangiocarcinoma.

This report contains the first description of a salivary gland tumour in a dasyurid marsupial; the same animal also had a mammary carcinoma. All the previously described neoplasms have been in animals held in captivity for varying periods of time, whereas the case reported here was a young animal trapped in the wild and killed three days later. The development of tumours in the natural environment is important aetiologically.

A seminoma and parathyroid adenoma were diagnosed in an aged snow leopard. The ultrastructural appearance of the seminoma was similar to that described in the dog and in man. The lack of significant amounts of rough endoplasmic reticulum, Golgi complexes and free ribosomes in the parathyroid adenoma suggested that it was non-functional. Parathyroid adenoma has not been previously described in a large wild feline.

A ten-year-old male nubian goat with no previous medical history was found recumbent. Clinical examination revealed an underweight, dehydrated, very depressed and unresponsive animal. At necropsy, the liver contained multiple, well-demarcated hepatocellular carcinomas. The right adrenal gland contained a solitary phaeochromocytoma. Multiple leiomyomas were present within the urinary bladder. The three primary neoplasms reported in this goat have been reported separately in other species; their simultaneous occurrence in one animal is uncommon.