Canine follicular cell and medullary thyroid carcinomas: Immunohistochemical characterization.

Research on modulation of iodine uptake by thyroid cells could help improve radioiodine treatment of dogs with thyroid tumors. The aim of this study was to characterize the immunohistochemical expression of thyroid transcription factor-1 (TTF-1), thyroglobulin, thyrotropin receptor (TSHR), sodium iodide symporter (NIS), pendrin, thyroid peroxidase (TPO), vimentin, and Ki-67 in follicular cell thyroid carcinomas (FTCs) and medullary thyroid carcinomas (MTCs), and to compare protein expression between FTC causing hyperthyroidism and FTC of euthyroid dogs. Immunohistochemistry was performed in 25 FTCs (9 follicular, 8 follicular-compact, and 8 compact) and 8 MTCs. FTCs and MTCs were positive for TTF-1, and expression was higher in FTCs of euthyroid dogs compared with FTCs of hyperthyroid dogs (P= .041). Immunolabeling for thyroglobulin was higher in follicular and follicular-compact FTCs compared with compact FTCs (P = .001), while vimentin expression was higher in follicular-compact FTCs compared with follicular FTCs (P = .011). The expression of TSHR, NIS, pendrin, and TPO was not significantly different among the different subtypes of FTCs or between FTCs causing hyperthyroidism and FTCs in euthyroid dogs. TSHR, NIS, pendrin, and TPO were also expressed in MTCs. Ki-67 labeling index was comparable between FTCs and MTCs, and between FTCs causing hyperthyroidism and FTCs in euthyroid dogs. Proteins of iodine transport were also expressed in canine MTCs, which could have implications for diagnosis and treatment. The different expression of thyroglobulin and vimentin between FTC histological subtypes could reflect variations in tumor differentiation.

Canine thyroid carcinomas: A review with emphasis on comparing the compact subtype of follicular thyroid carcinomas and medullary thyroid carcinomas.

Canine thyroid carcinomas are relatively common malignant endocrine neoplasms in dogs derived from either thyroid follicular cells (forming follicular thyroid carcinomas) or medullary cells (parafollicular, C-cells; forming medullary thyroid carcinomas). Older and recent clinical studies often fail to discriminate between compact cellular (solid) follicular thyroid carcinomas and medullary thyroid carcinomas, which may skew conclusions. The compact subtype of follicular thyroid carcinomas appears to be the least differentiated subtype of follicular thyroid carcinomas and needs to be differentiated from medullary thyroid carcinomas. This review includes information on the signalment, presentation, etiopathogenesis, classification, histologic and immunohistochemical diagnosis, clinical management, and biochemical and genetic derangements of canine follicular and medullary carcinomas, and their correlates with human medicine.

[Neuroendocrine carcinoma of the gallbladder as a rare cause for melena and hematemesis in dogs]. / Neuroendokrines Karzinom der Gallenblase als seltene Ursache für Meläna und Hämatemesis beim Hund.

A 9-year-old male Malinois was presented for further workup of acute melena, hematemesis and chronic weight loss for a duration of one month. Clinically, the patient presented with a mildly reduced general condition. Blood tests revealed mild non-regenerative anemia as well as a mild elevation of alanine aminotransferase (ALT). Ultrasonography showed signs of an early mucocele. Treatment with gastroprotectants failed to lead to clinical improvement and the dog developed progressive anemia. Gastroduodenoscopy was unremarkable. Due to persistent clinical signs, exploratory laparotomy was performed. An ulcerated bleeding mass was detected at the gallbladder neck. Histopathological examination led to the diagnosis of a neuroendocrine carcinoma. There was no evidence of a mucocele on histopathology. Melena and hematemesis subsided postoperatively and 13 months after cholecystectomy, the dog remains without clinical signs. Neuroendocrine carcinomas of the gallbladder should be considered as a rare cause of melena and hematemesis in dogs.

Multiorgan metastases with massive bone involvement of a medullary thyroid carcinoma in a dog.

A 10-year-old mixed-breed male dog was referred for a subcutaneous mass on the ventral neck. Based on total-body computed tomography (TBCT), the mass was located in the left thyroid lobe. Further alterations included enlargement of the ipsilateral mandibular and prescapular lymph nodes (LNs). Surgical excision of the mass and enlarged LNs was performed. Histopathology and immunohistochemistry were consistent with a medullary (C-cell) thyroid carcinoma, with no evidence of nodal metastases. Surgery was considered curative, and no medical treatment was provided. Periodic follow-up rechecks were unremarkable. After 18 months, the dog exhibited lethargy, vomiting, anorexia, and hind leg stiffness. TBCT revealed polyostotic osteopathy, and cytology suggested a metastatic endocrine carcinoma. Due to the dog's poor clinical condition and prognosis, the owner elected euthanasia, and a necropsy was performed. Based on gross pathology, histopathology, and immunohistochemistry, multiple metastases of the previous thyroid carcinoma were diagnosed, involving the occipital bone, multiple vertebrae, left sacral wing, fourth right rib, left scapula, left humerus, intrathoracic LNs, lung, spleen, and adrenal glands. This report describes a case of medullary thyroid carcinoma with distant multiorgan metastases and massive bone involvement after a disease-free interval of 18 months.

Gastric neuroendocrine carcinoma (carcinoid) in a ferret (Mustela putorius furo).

A well-differentiated neuroendocrine carcinoma of the stomach (gastric carcinoid) with transcoelomic and lymph node metastasis was confirmed on post-mortem examination of a 3-year-old, spayed female, domestic ferret (Mustela putorius furo). The animal was initially presented with a history of persistent vomiting which progressed to weight loss, a palpable abdominal mass, and melena. The ferret received palliative treatment and was euthanized 9 mo after initial presentation. The clinical, ultrasonographical, cytological, gross pathological, histopathological, and immunohistochemical findings are described. Gastric neuroendocrine carcinomas are rarely reported in animals; this is the first description in a ferret. Key clinical message: Veterinary practitioners and diagnosticians should include neuroendocrine carcinoma as a differential diagnosis when encountering gastric neoplasms in ferrets and be aware of the potential for aggressive behavior and widely spread metastasis.

Carcinome neuroendocrine gastrique (carcinoïde) chez un furet ( Mustela putorius furo ). Un carcinome neuroendocrinien bien différencié de l'estomac (carcinoïde gastrique) avec des métastases transcoelomiques et ganglionnaires a été confirmé lors de l'autopsie d'une femelle furet domestique (Mustela putorius furo) stérilisée de 3 ans. L'animal a été initialement présenté avec des antécédents de vomissements persistants qui ont évolué vers une perte de poids, une masse abdominale palpable et un méléna. Le furet a reçu un traitement palliatif et a été euthanasié 9 mois après la présentation initiale. Les résultats cliniques, échographiques, cytologiques, de pathologie macroscopique, histopathologiques et immunohistochimiques sont décrits. Les carcinomes neuroendocriniens gastriques sont rarement rapportés chez les animaux; c'est la première description chez un furet.Message clinique clé:Les praticiens vétérinaires et les diagnosticiens doivent inclure le carcinome neuroendocrinien comme diagnostic différentiel lorsqu'ils rencontrent des néoplasmes gastriques chez les furets et être conscients du potentiel de comportement agressif et de métastases largement disséminées.(Traduit par Dr Serge Messier).

Adenomatous Hyperplasia of Bowman's Capsule Epithelium in a Dog with Metastatic Nasal and Hepatic Neuroendocrine Carcinoma.

A 12-year-old spayed Shiba dog with a nasal neuroendocrine carcinoma and multiple hepatic nodules was necropsied. Histologically, proliferated blast cells with a monolayer or multilayered structure were observed in the kidney. This blast cell proliferation extended from Bowman's capsule epithelium to the proximal tubule in approximately 3% of nephrons. Immunohistochemistry revealed that blast cells were positive for vimentin, Wilm's tumour protein 1 (WT1), paired box 2 (PAX2) and CD10, but negative for cytokeratin (CK) AE1/AE3, CK19, CAM5.2, synaptophysin and chromogranin A. On the basis of these findings, adenomatous hyperplasia of Bowman's capsule epithelium was diagnosed. Multiple yellowish‒white nodules (1-3 cm) were found in the liver and diagnosed as neuroendocrine carcinoma with metastases to the lungs, adrenal glands and pancreaticoduodenal lymph nodes.

Alimentary Tract Neoplasia in Captive Bearded Dragons (Pogona spp).

There are multiple reports of gastric neuroendocrine carcinoma in bearded dragons (Pogona spp), but other types of alimentary neoplasia are rarely reported. In a retrospective study, we identified 51 cases of neoplasia, including gastric (n = 26), oral (n = 18), intestinal (n = 13), oesophageal (n = 3) and cloacal (n = 2) neoplasms. Round cell neoplasia was diagnosed in the alimentary tract in 14 cases, all of which had extra-alimentary involvement, most commonly in the liver, lung, spleen and kidney, and was considered to be the cause of death or euthanasia in all cases. Oral neoplasms included sarcoma, adenomatous polyp, round cell neoplasia, fibromatous epulis of periodontal ligament origin and myxoma. Apart from disseminated round cell neoplasia, all the oral neoplasms, including sarcomas, were not associated with death or euthanasia and had a good to excellent prognosis. Oesophageal neoplasms included round cell neoplasia. Gastric neoplasms included neuroendocrine carcinoma, round cell neoplasia, adenocarcinoma and sarcoma. Intestinal neoplasms included round cell neoplasia, sarcoma, adenocarcinoma and metastatic sarcoma. All oesophageal, gastric and intestinal neoplasms were associated with death or euthanasia and had a poor to grave prognosis. Cloacal neoplasms included round cell tumours and squamous cell carcinoma, and all were primary alimentary tumours except for the round cell tumours and one metastatic sarcoma. Round cell neoplasia and gastric neuroendocrine carcinoma were the most common diagnoses. Sarcomas and polyps were common in the oral cavity and rare to absent elsewhere. Adenocarcinoma was rare and only identified in the stomach and intestines.

Hypoglycemia and seizures associated with canine primary hepatic neuroendocrine carcinoma.

A 10-y-old intact male Labrador Retriever dog had a history of ataxia, inability to stand, and grand mal seizures. Complete blood count and serum biochemistry profiles revealed profound hypoglycemia, mildly increased alanine aminotransferase (ALT) activity, mild hypernatremia, and lymphopenia. The seizures could not be controlled with intravenous dextrose, diazepam, or propofol. The dog was euthanized given poor quality of life, and an autopsy was performed. Primary autopsy findings included firm hepatic masses that ranged from dark-red to tan, with the largest ~1.5 cm diameter, and pulmonary edema. Histologic examination of the hepatic masses revealed redundant, several-cell-thick cords, and packeted or acinar arrangements of polygonal cells, supported on a fibrovascular stroma. The neoplastic cells were immunopositive for insulin, synaptophysin, and neuron-specific enolase immunohistochemistry; granules in the tumor cells had an affinity for Grimelius silver stain. The histologic features, as well as the immunohistochemical staining profile, identified the neoplasm as a primary multifocal hepatic neuroendocrine carcinoma. Neuroendocrine carcinomas are rare in dogs and usually occur in the gastrointestinal or respiratory tract.

Pathological and Immunohistochemical Characterization of Thyroid Neoplasms in Cats.

There are few pathological and immunohistochemical descriptions of thyroid neoplasms in cats. We investigated neoplasms of the thyroid in 31 cats (average age 15.6 years) in Southern Brazil. Most (96.8%) of these cases were classified as follicular adenomas and were predominantly unilateral and multinodular. Histologically, macrofollicular adenomas were the most common type observed. Carcinomas represented 3.2% of the investigated tumours. By immunohistochemical labelling, thyroglobulin was expressed more commonly than paired box gene 8 or thyroid transcription factor 1 in the follicular adenomas. One carcinoma was immunopositive for thyroglobulin, pancytokeratin, chromogranin A and synaptophysin, suggestive of a calcitonin-negative neuroendocrine carcinoma.

Clinical, histopathologic, and immunohistochemical features of 13 cases of canine gallbladder neuroendocrine carcinoma.

In this retrospective descriptive study, we characterized the clinical, histologic, and immunohistochemical features of 13 cases of canine gallbladder neuroendocrine carcinoma (GB-NEC). Immunohistochemical stains for neuroendocrine (neuron-specific enolase [NSE], chromogranin A, synaptophysin) and gastrin markers were evaluated, and clinicopathologic and follow-up data were obtained for all cases. The average age at diagnosis was 8.9 y, and breeds included 6 Boston Terriers, 2 Bichon Frise, 1 Poodle, 1 English Bulldog, 1 French Bulldog, and 2 mixed-breed dogs. Boston Terriers were overrepresented in this cohort, and therefore a breed predilection is possible. Most dogs were presented with emesis and elevated liver enzyme activities: 13 of 13 had elevated alanine aminotransferase and alkaline phosphatase activities; 8 of 13 had elevated aspartate aminotransferase activity; 7 of 13 had elevated gamma-glutamyl transferase activity. Abdominal ultrasound and/or exploratory surgery revealed a gallbladder mass. All neoplasms had similar histologic features and positive immunoreactivity for NSE, chromogranin A, synaptophysin, and gastrin. Vascular invasion was noted in 8 of 13 neoplasms, and metastasis was present in 6 of 13 cases (4 hepatic and 2 pulmonary metastases). The median survival time was 3.7 y in patients who died; 5 of 8 deaths were directly attributed to the GB-NEC, 3 of which had metastatic spread. GB-NECs have the potential to metastasize; however, surgical excision may be curative in a subset of dogs.

Histopathological and Immunohistochemical Characteristics of Thyroid Carcinoma in the Dog.

Thyroid carcinomas are a common form of endocrine neoplasia in dogs. In the present study, we combined histopathology with immunohistochemistry (IHC) to search for the presence of oestrogen receptor alpha (ORα), Cox-2 and Ki67 in canine thyroid carcinomas. Forty-eight thyroid carcinomas were diagnosed throughout the study period. Thyroglobulin and calcitonin IHC distinguished between thyroid tumours with a follicular and medullary (C-cell) origin, respectively. IHC-based diagnosis showed that 42 (87.50%) of the cases were follicular cell carcinoma. In these cases, the follicular-compact pattern was the most frequent (n = 20/42; 47.62%) and six cases (12.5%) were medullary cell (C-cell) carcinomas. Both medullary (C-cell) and follicular carcinomas expressed Ki67 and Cox-2. No differences were observed between medullary and follicular carcinomas with respect to expression of Ki67 (P = 0.34) and Cox-2 (P = 0.9523) markers. A total of 4.17% (n = 2/48) of thyroid carcinomas showed positive nuclear labelling for ORα, suggesting that oestrogen does not directly participate in the pathogenesis of canine thyroid neoplasia.

Tumor carcinoide na vesícula biliar em cão / Carcinoid gallbladder tumor in a dog

Carcinoid is a neoplasia that arises from dispersed cells of the neuroendocrine system. This tumor is uncommon in animals, and its occurrence in the gallbladder is rare. A male Basset Hound dog's corpse was taken to the Univerdade Federal de Minas Gerais to be analyzed by the Veterinary Pathology sector, without a description of its previous history. Necropsy revealed the presence of pale oral, ocular and penile mucous membranes. The gallbladder had a thickened wall and a dilated lumen, which was filled with dark and lumpy bile. Its mucosa had a whitish-red nodule, with solid and friable areas. Microscopically, there was a focal neoplastic proliferation, which wasn't encapsulated and had imprecise limits, which cells were distributed in a solid pattern and separated by a delicate fibrovascular stroma. The neoplastic cells presented oval or round shaped nucleus, which had a chromatin predominantly loose, and one or two nucleoli. Their cytoplasm was moderately abundant, and in most of the cells it was eosinophilic, granular, and had well-defined limits. Using the Grimelius coloration, neoplastic cells' cytoplasmic granules stained brownish or black, confirming the neuroendocrine origin of the neoplasia. Based on the macroscopic and microscopic findings, the diagnosis of a gallbladder carcinoid was established.(AU)

Primary Unilateral Small Cell Neuroendocrine Carcinoma of the Kidney in a Dog.

Primary small cell carcinomas are rare in domestic animals. A mass measuring 15 × 20 × 9 cm was detected in the left abdominal cavity of a 7.5-year-old female golden retriever. The cut surface of the excised mass showed a tumour replacing the left kidney. Microscopically, the mass was composed of polymorphic, small basophilic cells with a high nuclear to cytoplasmic ratio and round, oval or short slender fusiform nuclei with condensed or finely granular chromatin, absent or inconspicuous nucleoli, and scant, faintly eosinophilic cytoplasm with poorly defined cytoplasmic borders. Immunohistochemically, most of the neoplastic cells were immunoreactive for thyroid transcription factor 1 and CD56, moderately positive for vimentin and weakly or sparsely labelled for chromogranin A, synaptophysin, Wilms' tumour 1 protein, neuron-specific enolase, pan-cytokeratin (CK) AE1/AE3 and epithelial membrane antigen. The tumour cells were negative for glial fibrillary acidic protein (GFAP), ionized calcium-binding adapter molecule 1, CK7, CK20, CD3, CD45 and CD99. These findings indicated a neuroendocrine origin of the tumour. To the best of author's knowledge, this is the first report of a small cell neuroendocrine carcinoma originating as a primary tumour in the kidney of a dog.

Hepatic neuroendocrine carcinoma with metastases to the lymph nodes in a sika deer (Cervus nippon yakushimae).

A 26-year and 6-month-old male sika deer that was kept at the Showa Park, Tokyo, Japan, collapsed and died of severe disease wasting and severe tabefaction. Grossly, numerous masses, 0.3-1.0 cm diameter, were dispersed throughout the liver. The multiple masses were composed of tumor cells, which had hypochromatic nuclei and abundant faintly eosinophilic cytoplasm, arranged in nests of various sizes. Immunohistochemically, tumor cells were positive for cytokeratin, chromogranin A, synaptophysin and gastrin. Ultrastructurally, the cytoplasm of the tumor cells contained abundant membrane-bound electron-dense granules. A metastatic lesion was observed in the renal, hepatic and pancreatic lymph nodes. On the basis of these findings, this tumor was diagnosed as a neuroendocrine carcinoma with metastases to the lymph nodes.

Primary Hepatic Neuroendocrine Carcinoma Treated with Doxorubicin and Cyclophosphamide in a Dog.

A 7 yr, 6 mo old male neutered Australian cattle dog cross presented to a referral hospital with a large abdominal mass. An abdominal ultrasound revealed multifocal lesions throughout the liver, which were suspicious for intrahepatic metastasis, with no evidence of extrahepatic metastatic disease. Cytology indicated neoplasia of epithelial origin, with neuroendocrine neoplasia the primary suspicion. The patient was started on a maximally tolerated chemotherapy protocol of doxorubicin and metronomic cyclophosphamide. Stable disease was found on repeat abdominal ultrasounds, and the patient tolerated the protocol well. On completion of five doxorubicin doses, the dog was continued on metronomic cyclophosphamide and meloxicam. Progressive hepatic disease was found at 10 mo. The patient was euthanized 15.5 mo (465 days) after commencing treatment. Histopathology and immunohistochemistry (synaptophysin) performed on liver collected postmortem indicated (primary) hepatic neuroendocrine carcinoma. Primary hepatic neuroendocrine carcinomas are rare in dogs, and there is no standard of care for treatment. To the authors' knowledge, this is the first report of a primary hepatic neuroendocrine carcinoma treated with high-dose doxorubicin and metronomic cyclophosphamide.

Mixed Malignant Pancreatic Tumour in a Rhesus Macaque (Macaca mullata).

Pancreatic islet cell tumours are rare in non-human primates. The majority of reported cases are benign islet cell adenomas in rhesus macaques (Macaca mullata). Here we describe a pancreatic tumour composed of both exocrine and endocrine cells known as a mixed acinar-neuroendocrine carcinoma in a captive rhesus macaque. A diagnosis of a mixed tumour requires intermingling of neoplastic exocrine and neuroendocrine cells and must be differentiated from ductal adenocarcinomas in which only the ductal component is neoplastic with interspersed normal neuroendocrine cells. Immunohistochemistry, including antibodies against cytokeratin 7 and chromogranin A, was used to demonstrate that both exocrine and endocrine neoplastic cells exhibited cellular atypia, invasion into the adjacent parenchyma and intraparenchymal metastasis consistent with a mixed malignant tumour. Expression of multiple hormones such as gastrin, insulin, pancreatic polypeptide and somatostatin was also observed throughout the neoplastic cell population, while the endocrine component of the neoplasm was predominantly positive for glucagon.

Hepatic neuroendocrine carcinoma in a Japanese macaque (Macaca fuscata).

Primary neuroendocrine neoplasm of the liver is extremely rare in both humans and non-human primates. The present report describes the clinical and pathological findings of an aged Japanese macaque (Macaca fuscata) with hepatic neuroendocrine carcinoma. To our knowledge, this is the first report of hepatic neuroendocrine neoplasm in macaques.

Pancreatic neuroendocrine carcinoma with exocrine differentiation in a young cat.

A 35-mo-old spayed female mixed-breed cat with continuous vomiting, emaciation, and abdominal distention for 2 wk was presented to a private veterinary clinic for evaluation. At 71 d after the initial visit, the cat died with anemia, jaundice, and hypoalbuminemia, and was subjected to autopsy. Grossly, numerous firm masses, 0.5-2.5 cm diameter, were randomly located in the left lobe of the pancreas. Histologic examination revealed that the pancreatic mass consisted of 2 tumor cell types: mostly small round cells with a minority of epithelial cells. The small cells were arranged in nests of various sizes, which were separated by thin fibrous stroma, and had small, round, hyperchromatic nuclei, scant cytoplasm containing argyrophilic granules, and often formed rosettes. The epithelial cells formed luminal structures. Metastases were observed in the liver, greater omentum, and pancreatic, gastric, pulmonary, and mediastinal lymph nodes. Immunohistochemical examination revealed that the small cells were positive for vimentin, neuron-specific enolase, chromogranin A, cytokeratin (CK) AE1/AE3, and trypsin, whereas the epithelial cells were positive for AE1/AE3, trypsin, CK19, and nestin. Ultrastructurally, the small cells contained abundant electron-dense granules, ~200 nm diameter, whereas the epithelial cells had apical microvilli and numerous zymogen granules, ~300 nm diameter. These findings indicated that the tumor was a pancreatic neuroendocrine carcinoma with exocrine differentiation and systemic metastases.

Spontaneous proliferative and neoplastic lesions in thyroid and parathyroid glands of nondomestic felids.

Based on microscopic and immunohistochemical characterization, we documented spontaneous proliferative and neoplastic lesions in the thyroid and parathyroid glands of nondomestic felids. Ten animals (4 leopards, 3 tigers, and 3 cougars), all with a previous diagnosis of thyroid neoplasia were identified from the University of Tennessee College of Veterinary Medicine database. The mean age of affected animals was 15.9 y. Twelve neoplasms were identified; 2 animals had 2 concurrent neoplasms. After immunohistochemical characterization using a panel of chromogranin A, thyroglobulin, and calcitonin, 7 of the former thyroid neoplasms were diagnosed as thyroid adenomas, 1 was diagnosed as a thyroid carcinoma, and 4 were diagnosed as parathyroid adenomas. No thyroid medullary neoplasms (C-cell tumors) were diagnosed in the current study. Most of the diagnosed neoplasms were benign (11 of 12), and metastasis was not documented in the single carcinoma. Only 2 animals were suspected to have functional neoplasms (1 thyroid adenoma and 1 parathyroid adenoma), based on associated tissue lesions or serum biochemistry. Other documented lesions in the thyroid and parathyroid glands included thyroid nodular hyperplasia ( n = 7), parathyroid hyperplasia associated with chronic renal disease ( n = 2), a thyroid abscess, and a branchial cyst. Parathyroid adenomas were more commonly diagnosed than expected in comparison with domestic cats. We demonstrated that an immunohistochemistry panel for thyroglobulin, calcitonin, and chromogranin A can be used to differentiate neoplasms of thyroid from parathyroid origin in nondomestic felids.

Metastatic neuroendocrine carcinoma of aortic body origin in a cat.

An 8-year-old, female spayed Domestic Shorthair cat was presented to the Auburn University Emergency and Critical Care service for evaluation of pleural effusion and a suspected intrathoracic mass. Computed tomography was performed which confirmed the presence of a large intrathoracic mass, likely heart-based. Fine-needle aspirates were obtained and a cytologic diagnosis of a neuroendocrine tumor was made. Treatment with toceranib phosphate was briefly attempted at home by the owners. The cat died at home approximately 6 weeks after diagnosis. Necropsy and subsequent histopathologic examination revealed a metastatic neuroendocrine carcinoma of aortic body origin. Aortic body tumors are extremely rare in cats and to the authors' knowledge, a neuroendocrine carcinoma of aortic body origin with distant metastases has not yet been reported in a cat.