Primary localized nodular cutaneous amyloidosis in a male neutered Golden Retriever

Cutaneous amyloidosis occurs as primary localized form or secondary to systemic amyloidosis. In dogs, cutaneous amyloidosis is reported in association with localized plasma cell proliferation or cutaneous extramedullary plasmacytoma. Primary cutaneous amyloidosis is a very rare condition in dogs. There is paucity of information and published report on primary nodular cutaneous amyloidosis in dogs. This report describes a case of primary nodular cutaneous amyloidosis for the first time in a male Golden Retriever.     

Idiopathic telangiectasia in a Golden Retriever

A case report of a 12-year-old spayed female Golden Retriever with a 4-month history of persistent diffuse erythema involving the right and left antebrachia is presented. Cutaneous biopsies revealed superficial dermal vascular dilation and proliferation with moderate epidermal acanthosis. Diagnostic tests failed to reveal an underlying aetiology. Telangiectasia is defined as a permanent dilation of pre-existing blood vessels creating small focal lesions. Generalized essential telangiectasia of humans is common in women of middle-age and can involve entire segments of the body. Lesions predominantly affect the extremities and can persist for years without any systemic effects. The cutaneous lesions in this case have remained static for 3 years with no manifestation of systemic signs. A diagnosis of idiopathic telangiectasia was made based on the clinical and histological findings in the dog of this report. The lesions described in this dog resemble generalized essential telangiectasia of humans.     

Dendritic cell leukemia in a Golden Retriever

An 8-year-old castrated male Golden Retriever was evaluated for decreased appetite, lethargy, and labored breathing of 1-week duration. Bilateral pulmonary infiltrates, hepatomegaly, and splenomegaly were present. Results of a CBC revealed marked leukocytosis (62,600/microL; reference interval 4000-15,500/microL) and large numbers of atypical cells (30,700/microL) with abundant cytoplasm. There was no concurrent anemia, neutropenia, or thrombocytopenia. Morphology of the atypical cells was most consistent with a histiocytic origin. Similar cells were identified in bone marrow aspirates, and were morphologically suggestive of the macrophage variant of disseminated histiocytic sarcoma. However, flow cytometry of the abnormal circulating cells revealed CD1c, CD11c, and major histocompatibility complex (MHC) Class II expression without expression of CD11d or lymphoid markers, consistent with myeloid dendritic antigen-presenting cells. At necropsy, the splenic architecture was effaced by neoplastic histiocytes that were also infiltrating lung, liver, an abdominal lymph node, myocardium, an bone marrow. Immunohistochemistry of the splenic neoplastic cells confirmed dendritic cell origin (CD1c+, CD11c+, MHC II+, no expression of CD11d and lymphoid markers). To the authors' knowledge, this is the first report of canine dendritic cell leukemia-in this instance accompanied by marked tissue infiltration.     

Nodular Dermatofibrosis and Renal Cystadenomas in a Golden Retriever

Abstract— The clinical and histologic features of a 2-year-old intact male golden retriever with nodular dermatofibrosis and renal cystadenomas are described. The skin lesions failed to respond to antibiotic and glucocorticoid therapy. Abdominal ultrasound revealed a wedge-shaped area of hyperechoic mottled echogenicity at the cranial pole of the left kidney and a small right kidney. Euthanasia was performed thirty-six months following initial presentation, owing to progressive enlargement of the dermal and subcutaneous nodules and gross deformity of the left hind limb secondary to fibrous tissue deposition and lymphatic obstruction. Necropsy confirmed the presence of bilateral renal cystic hyperplasia and multifocal renal cystadenomas. This is the first confirmed report of nodular dermatofibrosis and renal cystadenomas in a breed other than the German shepherd dog.     

Hydrocephalus and hypertrichosis in Golden Retriever dogs

Congenital hydrocephalus has been reported in most species of domestic animals and is one of the most common congenital malformations of the canine central nervous system⁽¹⁾. Small, toy and brachycephalic breeds are at higher risk of hydrocephalus than larger breeds. Newborn and immature hydrocephalic puppies typically show an enlarged, domeshaped cranium, open fontanelles, visual and auditory impairment, poor growth rate and sometimes an uncoordinated gait. The pathogenesis of hydrocephalus is unclear but inheritance as an autosomal recessive trait has been identified in some breeds. Suspected inherited polymicrogyria and hydrocephalus has been identified in young Standard Poodles and a similar condition seen in a Golden Retriever dog in the USA⁽¹⁾. During the past 2 years, congenital and suspected inherited (as an autosomal recessive trait) hydrocephalus has been diagnosed in Golden Retriever puppies in New Zealand.     

Hereditary spectrin deficiency in Golden Retriever dogs

Spectrin deficiency with increased erythrocyte osmotic fragility (OF) is a hallmark of hereditary spherocytosis, which is the most common congenital hemolytic anemia in humans of northern European ancestry. A radioimmunoassay revealed that erythrocyte spectrin concentration was 50-65% of normal in 5 adult Golden Retriever dogs, which had recovered from hemolytic anemia but whose OF had persistently remained increased. OF also was increased and spectrin concentration was decreased (60-73%) in 10 dogs of an apparently healthy family of 19 Golden Retrievers related to a proband. Pedigree analysis revealed autosomal dominant inheritance. In addition, OF was increased in 23 (17%) of 134 randomly chosen Golden Retrievers with nonhematologic diseases. In these Golden Retrievers, the spectrin concentration was decreased in 5 dogs with increased OF and within the reference range in 6 dogs with normal OF, indicating that in this population spectrin deficiency and increased OF are highly associated (P < .002). Considering these patients a representative sample of the Golden Retriever population in the Netherlands, spectrin deficiency may occur in 11.2-24.6% of Dutch Golden Retrievers (confidence level = 0.95). In blood smears, spherocytes were recognized only in dogs with immune-mediated anemia. At scanning electron microscopy, blood from spectrin-deficient Golden Retrievers showed slight crenation when fixed freshly but abundant echinospherocytes after 24 hours of incubation. We conclude that occult autosomal dominant spectrin deficiency occurs in dogs and is frequent in Dutch Golden Retrievers. It is not clear whether spectrin deficiency in Golden Retrievers may result in hemolytic anemia, as in humans.     

The electroretinographic phenotype of dogs with Golden Retriever muscular dystrophy

Objective To characterize the flash electroretinogram (ERG) in the Golden Retriever muscular dystrophy (GRMD) dog and to compare the results with those from a control group of Golden Retrievers. To investigate whether similar abnormalities of the ERG as those found in a majority of human patients with Duchenne muscular dystrophy (DMD) are also observed in the GRMD dog, the canine model for DMD. Animals Five GRMD dogs and five age‐matched clinically normal Golden Retrievers. Procedure An ophthalmic examination was carried out prior to performing electroretinography under general anesthesia. Rod, combined rod–cone and oscillatory potentials responses were recorded after dark adaptation. Responses to 30‐Hz‐flicker were recorded after light adaptation. The ERG responses of the GRMD dogs were compared with those of the control dogs by use of a Wilcoxon signed rank test. Results GRMD dogs had significantly reduced a and b‐wave amplitudes after dim white flash stimuli (rod response) and reduced a‐wave amplitude after bright white flash stimuli (rod–cone response). Conclusion and clinical relevance The ERG abnormalities observed in the GRMD dog suggest a dysfunction in the rod signaling pathway. These ERG alterations are different from those observed in human patients with DMD.     

Uterine myxoid leiomyosarcoma with widespread metastases in a cat

A 10-year-old domestic shorthair cat was spayed to remove bilateral ovarian masses and an enlarged uterus. Both ovaries were effaced by large, irregular, firm, glistening, white cystic masses filled with clear viscous fluid. The uterine lumen was filled with copious amounts of clear viscous fluid, and the uterus contained multiple, firm, glistening, white nodules. Histologic examination revealed an invasive spindle cell neoplasm with features of malignancy, and extensive hypocellular areas containing an alcian blue-positive myxoid matrix. Tumor cells expressed caldesmon, alpha-smooth muscle actin, and estrogen receptor but were negative for desmin. The animal was euthanized 1 month later because of suspected local tumor recurrence. At necropsy, the abdominal cavity contained 120 ml of mucoid ascites; multiple tumor nodules were present in the abdominal and thoracic cavities. The clinical behavior and gross, microscopic, and immunohistochemical findings established a diagnosis of myxoid leiomyosarcoma.     

Seminoma with cutaneous metastases in a dog

A 10-year-old Great Pyrenees was presented for anorexia and weight loss. On physical examination, the dog was emaciated and showed a large ulcerated lesion on the right lower lip in addition to an enlarged right testicle. Fine-needle aspiration biopsy of the testicle and surgical biopsy of the lip lesion were performed; the histopathological report was consistent with metastatic seminoma. The diagnostic and therapeutic approach in this unusual metastatic seminoma is presented and compared to the previous literature. A multimodality therapy consisting of surgery and chemotherapy is proposed for the clinical management of metastatic seminoma in dogs.     

Primary bone marrow T‐cell lymphoma in a Golden Retriever

A 6.2‐year‐old 28‐kg (61.7 lb) intact female Golden Retriever was referred due to persistent and multiple cytopenias noted on a routine CBC prior to a mature ovariohysterectomy procedure. The patient's physical examination was unremarkable, and staging of the thorax and abdomen identified no abnormalities. At the referral hospital, moderate hypercalcemia, borderline anemia, and neutropenia were noted. Assessment of bone marrow samples by cytology, histology, immunohistochemistry, and flow cytometry indicated a T‐cell neoplasm. The patient was treated with a multi‐agent chemotherapy protocol for 6 months, which induced remission. Nine months after diagnosis, she relapsed with recurrence of hypercalcemia, cytopenias, and clinical illness. Single‐agent anthracycline (mitoxantrone) in combination with prednisone therapy was initiated for 3 months. Two months after completion, the patient relapsed again, and palliative therapy with prednisone was elected. The patient was euthanized 16 months after diagnosis due to progressive disease. Post‐mortem histopathologic evaluation showed extensive replacement of bone marrow by neoplastic cells, and infiltrates in multiple organs. The neoplasm was diagnosed as lymphoma rather than leukemia due to the lack of abnormal circulating cells throughout the course of disease. The neoplasm was detected only in marrow at the time of initial diagnosis, and the marrow was the most extensively effaced organ at the time of death. Therefore, leukemia or stage V lymphoma was considered unlikely. In patients with a cytopenia and lack of neoplastic leukocytosis or solid tissue masses, primary bone marrow lymphoma should be considered among the differential diagnoses.     

Cosegregation of a factor VIII microsatellite marker with mild hemophilia A in Golden Retriever dogs

Mild hemophilia A (factor VIII deficiency) was diagnosed in Golden Retrievers and pedigree studies were undertaken to test the cosegregation of an intragenic factor VIII marker with the disease phenotype. The study population consisted of 30 client-owned dogs (22 males and 8 females). Hemophilic males (n = 12) typically demonstrated prolonged bleeding after trauma or surgery rather than spontaneous hemorrhagic events. The affected males had a proportionate reduction in factor VIII coagulant activity (mean FVIII:C = 4%) and factor VIII protein concentration (mean FVIII:Ag = 3%). Twenty-five dogs (10 affected males, 8 clear males, 2 obligate carrier dams, and 5 suspect carrier daughters) were genotyped for a factor VIII microsatellite marker, with allele size assigned by an automated capillary electrophoresis system. Five distinct marker alleles were present in the study pedigree and a 300-base pair allele was found to segregate with the hemophilia A phenotype. The inheritance of the hemophilia-associated allele defined carrier status for 5 suspect daughters of obligate carrier dams. The limitations inherent to linkage analyses (i.e., lack of access to key family members and homozygosity at the marker locus) did not preclude carrier detection in this pedigree. We conclude that genotype analysis for the intragenic factor VIII marker can aid in control of canine hemophilia A through enhanced carrier detection.     

Primary conjunctival mast cell tumor in a Labrador Retriever

A 4-year-old, intact male Labrador Retriever with a rapidly progressive conjunctival mass was evaluated. Ocular examination showed a 2-cm elongated mass arising from the superior bulbar conjunctiva of the left eye. The mass resulted in distortion of the palpebral fissure and contacted the superior aspect of the cornea without modifying its structure; no adhesion to the sclera was detected. The superior palpebral conjunctiva was unaffected, and the remaining ocular examination was normal. The initial diagnostic work-up included CBC, serum biochemical analysis, urinalysis, and fine needle biopsy of the mass. A poorly differentiated mast cell tumor was diagnosed by cytology. Immunocytochemistry was performed to evaluate Ki-67 proliferation index, and 54/1000 tumoral nuclei showed a dark red staining. After a complete clinical staging, the mass was excised and identified histologically as a grade-II mast cell tumor. An adjuvant treatment with prednisone and vinblastine was instituted because of the limited excisional margins. No evidence of local recurrence or metastasis has been apparent during the 29-month follow-up period. This report contributes to the current literature pertaining to canine conjunctival mast cell tumors; unfortunately, the paucity of case reports and the absence of large studies regarding this tumor make conclusions regarding its biologic behavior impossible.     

Cutaneous mass aspirate from a Golden Retriever: "glandular guile"

A 3-year-old, neutered, male Golden Retriever was presented for evaluation of a 10 X 9 X 5 mm, firm, red, raised, cutaneous mass located over the left cranial thorax and noted incidentally by the owner. On cytologic evaluation of a fine-needle aspirate of the mass, the interpretation was a malignant tumor with predominantly mesenchymal features. Differentials included liposarcoma, atypical amelanotic melanoma, anaplastic sarcoma, and anaplastic carcinoma. Following complete excision of the mass, a diagnosis of sebaceous adenocarcinoma was made based on histologic features, positive immunostaining for pancytokeratin, and negative staining for vimentin, Melan-A, and S-100. There was no evidence of metastasis on physical examination or thoracic radiographs, and the prognosis was good. The unique and previously unreported cytologic features of this small, sebaceous adenocarcinoma were the extreme pleomorphism, including marked anisocytosis, anisokaryosis, and multinuclearity, and the paucity of epithelial features.     

Primary infundibular stenosis and pedigree analysis in three Golden Retriever littermates

Three eight-week-old Golden Retriever puppy littermates were evaluated because of left basilar systolic murmurs and were diagnosed with primary infundibular stenosis. Pedigree analysis in this line was also performed to identify a mode of inheritance. All dogs were asymptomatic at the time of diagnosis; two of the three had congenital lesions in addition to primary infundibular stenosis. Two additional affected dogs were identified in the line, and pedigree analysis suggested an autosomal recessive mode of inheritance. Another, unrelated golden retriever was also identified with isolated infundibular stenosis in the record database. Primary infundibular stenosis should be considered in the differential diagnoses for golden retriever dogs with a left basilar systolic murmur, and is often associated with complex congenital cardiac disease. Primary infundibular stenosis may worsen in severity with time, and in this line of dogs an autosomal recessive pattern of inheritance is likely.     

Extensive cutaneous metastases in a dog with duodenal adenocarcinoma

Abstract: A 6-year-old Rottweiler was presented to the North Carolina State University College of Veterinary Medicine for evaluation of multiple cutaneous nodules. The dog had a history of anorexia, vomiting, and hind-limb paraplegia. Results of cytologic examination of the cutaneous nodules were consistent with a round cell tumor. At necropsy, primary tumors were found coalescing in the duodenum and the pancreas and extending into the associated mesentery. Numerous masses also were found throughout the skin, abdominal and thoracic viscera, and lumbar spinal cord. Histologically, the duodenal tumor had variable morphology, with some areas resembling adenocarcinoma and others resembling anaplastic round cell neoplasia; the skin and other metastatic lesions resembled round cell neoplasia. Immunohistochemistry of the cutaneous, duodenal, and pancreatic masses showed the neoplastic cells were positive for pancytokeratin, supporting an epithelial origin. In addition, low numbers of neoplastic cells were positive for periodic acid-Schiff and Alcian blue, consistent with acid mucin production by duodenal epithelium. These findings confirmed that the cutaneous nodules were metastatic lesions originating from the duodenal adenocarcinoma. Cutaneous metastasis of intestinal carcinoma is rare in domestic animals. This case demonstrates the potential difficulty in diagnosing metastatic lesions based on cytologic and histologic morphology alone, because the cutaneous metastases may not resemble the primary neoplasm morphologically.     

Association between Aortoseptal Angle in Golden Retriever Puppies and Subaortic Stenosis in Adulthood

Background

Predicting subaortic stenosis (SAS) in adult Golden Retriever dogs (GRs) by evaluating them as puppies is hampered by the progressive expression of the SAS phenotype in youth. In some children who develop SAS as adults, an abnormal aortoseptal angle (AoSA) precedes development of stenosis.

Objectives

To determine the normal AoSA in young adult GRs using echocardiography; to assess the value of AoSA in GR puppies for predicting development of the SAS phenotype.

Animals

Forty‐eight 2‐ to 6‐month‐old GR puppies.

Methods

Prospective study. Puppies were recruited from clients and breeders. Puppies were evaluated with a physical examination and an echocardiogram, and this evaluation was repeated when they were 12–18‐month‐old adults. Puppies were classified as unaffected (WNL) or affected (SAS) retroactively, based on their results as adults.

Results

In WNL young adult GRs, mean ± SD AoSA was 152.3 ± 6.5°. Mean ± SD AoSA in SAS puppies (144.9 ± 8.6°) was significantly different from mean AoSA in WNL puppies (155.7 ± 8.8°, P < .01). No puppy with AoSA >160° had the SAS phenotype as a young adult; 93% (75.7–99.1%) of puppies with AoSA <145° had the SAS phenotype as young adults. Peak LVOT velocity increased significantly between evaluations (P < .0001) whereas AoSA did not (P = .45).

Conclusion and Clinical Significance

A steep AoSA in GR puppies is associated with the SAS phenotype in young adulthood. Some GR puppies have an abnormal AoSA that persists in young adulthood and is detectable before peak LVOT velocity reaches levels consistent with SAS.     

Descriptive analysis of haemangiosarcoma occurrence in dogs enrolled in the Golden Retriever lifetime study

Haemangiosarcoma is a relatively common malignant tumour in dogs, and one of the primary outcomes of interest for the Golden Retriever Lifetime Study. This study collects longitudinal data and samples from a cohort of golden retrievers, with the aim of identification of nutritional, genetic, environmental, lifestyle and reproductive risk factors for cancers and other important diseases in dogs. This analysis describes the accumulating data and samples, which are available for use by researchers to fulfil the study's objectives. As of September 2022, 233/3044 dogs enrolled in the study had been diagnosed with haemangiosarcoma (7.65%), with an incidence rate of 1.10 cases per 100 dog-years. Visceral haemangiosarcoma was the most common, affecting 211/3044 study dogs (6.9%). One hundred and twenty eight visceral haemangiosarcoma diagnoses specified the presence of splenic tumours (60.7%) and 119 specified the presence of cardiac tumours (56.4%). The probability of remaining without a haemangiosarcoma diagnosis declined from 100% from approximately 4 years of age, to a 12 year probability of 91.1% in intact females (95% CI 84.4%–98.3%), 60.7% in neutered females (95% CI 41.6%–88.6%), 72.9% in intact males (95% CI 62.9%–84.6%) and 70.0% in neutered males (95% CI 53.4%–92.0%). The 1 year survival probability for visceral haemangiosarcoma was 1.42% (95% CI 0.37%–5.47%); for cutaneous haemangiosarcoma, it was 84.6% (95% CI 67.1%–99.99%). The accumulated data and samples are a considerable resource for further investigation of canine haemangiosarcoma and have a potential role in translational medicine.