Spinal nephroblastoma in a crossbreed dog

A three-year-old, male crossbreed dog presented with progressive hindlimb paresis. Magnetic resonance imaging revealed an intramedullary spinal cord lesion of 1.5 cm diameter at the levels of the first and second lumbar vertebrae. Following surgical excision of the mass, there was resolution of the neurological signs. Twelve months later, hindlimb paresis was again evident. A second surgical procedure restored ambulatory status for a further five months before signs recurred and the dog was euthanased. A diagnosis of spinal nephroblastoma was made on the basis of signalment, lesion location and histopathological analysis of biopsy specimens.     

Spinal nephroblastoma in a miniature Dachshund

A 2-year-old castrated miniature Dachshund dog was presented to the Rakuno Gakuen Veterinary Teaching Hospital for diagnosis of progressive hindlimb paresis and ataxia. There was no thoracolumbar intervertebral disk hernia and magnetic resonance imaging revealed an intramedullary spinal cord lesion at the ninth and tenth thoracic vertebrae. Following surgical excision of the neoplasm, there was minor amelioration of neurological signs, but forelimb function was not recovered. The extracted tumor was histopathlogically diagnosed as spinal nephroblastoma.     

Spinal nephroblastoma in an Irish wolfhound

A 1-year-old Irish wolfhound was presented with a history of slowly progressive left pelvic limb paresis. A neurological examination demonstrated bilateral deficits referable to the thoracolumbar spinal cord. Lumbar cerebrospinal fluid contained neoplastic cells. An intradural, extramedullary mass was demonstrated by myelography at the caudal aspect of T13. Surgical excision was abandoned owing to severe macroscopic damage to, and apparent infiltration of, the cord, and the dog was euthanased. The tumour was diagnosed histologically as an extrarenal nephroblastoma. Nephroblastoma should be suspected in young, large-breed dogs with intradural extramedullary masses over spinal segments T10-L2. The prognosis for complete recovery after surgical excision is guarded to poor.     

Treatment of renal nephroblastoma in an adult dog

An 8-year-old Labrador retriever was diagnosed with a unilateral malignant nephroblastoma and hypertrophic osteopathy. The histopathologically malignant tumor was confined to the renal capsule, but the sarcomatous component was anaplastic, resulting in its classification as a Stage I tumor with unfavorable histopathology. The dog was treated with unilateral nephrectomy, vincristine, and doxorubicin. This dog has remained disease free for >25 months. Reported treatments of renal nephroblastoma in the dog have not described disease-free intervals of >8 months.     

Nasopharyngeal nephroblastoma in a 3-month-old Boer goat

A 3-mo-old, female Boer goat was presented because of respiratory difficulties. Tachypnea and inspiratory dyspnea were noted during physical examination. Thoracic radiographs were unremarkable; however, upper airway and nasal passage radiographs revealed a soft tissue mass within the nasal passages. The patient underwent cardiorespiratory arrest and did not respond to resuscitation efforts during endoscopy. A large, pedunculated, semi-firm mass originated from the soft palate and obstructed 90% of the nasopharynx on autopsy. Histologically, the mass was composed of primitive cells that multifocally formed tubules and glomeruloid structures intermingled with areas of fusiform and blastemal cells. The neoplastic cells were positive for cytokeratin (tubular and glomeruloid cells), vimentin (fusiform population and blastemal cells), and Wilms tumor 1 protein (glomeruloid structures) on immunohistochemistry, consistent with a triphasic nephroblastoma. To our knowledge, nasopharyngeal nephroblastoma has not been reported previously in any species.     

Renal nephroblastoma in a 3-month-old golden retriever

Nephrectomy was performed in a 3-month-old intact female golden retriever dog for a renal nephroblastoma. The dog has remained disease-free for 19 months with nephrectomy alone. The adoption of human Wilms’ tumor grading criteria may be useful in determining clinical stage, adjuvant treatment options, and prognosis in this rare disease.     

Porcine Circovirus Type 2 and Porcine Circovirus-Associated Disease

Porcine circovirus type 2 (PCV2) belongs to the viral family Circoviridae and to the genus Circovirus . Circoviruses are small, single-stranded nonenveloped DNA viruses that have an unsegmented circular genome. PCV2 is the primary causative agent of several syndromes collectively known as porcine circovirus-associated disease (PCVAD). Many of the syndromes associated with PCVAD are a result of coinfection with PCV2 virus and other agents such as Mycoplasma and porcine reproductive and respiratory syndrome virus. PCV2 infection is present in every major swine-producing country in the world, and the number of identified cases of PCVAD is rapidly increasing. In the United States, the disease has cost producers an average of 3–4 dollars per pig with peak losses ranging up to 20 dollars per pig. The importance of this disease has stimulated investigations aimed at identifying risk factors associated with infection and minimizing these risks through modified management practices and development of vaccination strategies. This paper provides an overview of current knowledge relating to PCV2 and PCVAD with an emphasis on information relevant to the swine veterinarian.     

Extradural spinal,bone marrow,and renal nephroblastoma

A 1-year-old, female intact Shetland sheepdog presented with acute onset of neurological signs. Physical examination revealed a large abdominal mass. Neurological examination revealed multifocal disease with neck pain, short-strided forelimbs, and hind-limb paresis with loss of tail and anal tone. Blood work, imaging techniques, cytopathology, and histopathology led to a diagnosis of renal, bone-marrow, and extradural spinal nephroblastoma. This report documents potential clinical and pathological manifestations of canine nephroblastoma that have not been previously reported.     

Possible intraspinal metastasis of a canine spinal cord nephroblastoma

A 2-year-old Basset Hound was admitted to the University of Florida Veterinary Medical Teaching Hospital with progressive spastic paraparesis. At necropsy, intradural extramedullary tumors produced areas of spinal cord swelling and softening in spinal cord segments T11-T12 and L4-L6. Histologic examination of the masses revealed sheets of polygonal blastemal cells, epithelial cells forming tubules and rosettes, and embryonal glomeruloid-like structures in the thoracic mass. Cells in the lumbar mass were less differentiated, forming rare tubules and no glomeruloid-like structures. The occurrence of two tumors in the spinal cord along with the less differentiated appearance of the lumbar tumor raises the possibility that the lumbar mass arose as a result of intraspinal metastasis. To our knowledge, this is the first report of multifocal or metastatic canine spinal nephroblastoma. In addition, the vimentin and cytokeratin immunohistochemical staining characteristics of these spinal cord nephroblastomas are described.     

Proliferative potential of a spinal nephroblastoma in a young dog

The proliferative potential of a spinal nephroblastoma was studied in a young dog. A 4-month-old, female golden retriever showed developing deterioration in her gait and subsequent paralysis of her hind legs. At necropsy, a well-demarcated grayish brown tumor mass was found in the lumbar spinal cord segments between L2 and L3. Histologically, a blastemal cell tumor with a tubule- or glomeruli-like structure was found to be infiltrating intradurally. Proliferating cells at the S-phase, assessed using the bromodeoxyuridine (BrdU) labeling method, were seen occasionally in the tubular cells and glomeruli-like structures and were frequently seen in the blastemal cells. Immunohistochemically, the tubular epithelial cells were positive for cytokeratin, and the blastemal cells were positive for vimentin. The present tumor showed a high potential for growth and invasion, which suggests that it the potential to expand into the adjacent spinal cord.     

Intrarenal pelvic nephroblastoma in a meerkat (Suricata suricatta).

Nephroblastoma is the most common primary renal tumor in children and has also been reported in domestic and nondomestic animal species. Intrapelvic renal nephroblastoma is a rare variant of this tumor type in human patients. Postmortem examination of a captive meerkat (Suricata suricatta), which was found dead, revealed enlargement of the pelvis of the left kidney by a tumor mass. Gross, histological, and immunohistochemical findings were consistent with a diagnosis of triphasic intrapelvic renal nephroblastoma. This is the first reported spontaneous case of intrapelvic renal nephroblastoma in a nonhuman species.     

Malignant nephroblastoma in a common marmoset (Callithrix jacchus)

Necropsy of a 17-month-old male common marmoset (Callithrix jacchus) with a history of increased abdominal girth resulted in the finding of a unilateral polycystic renal neoplasm. Detailed histopathologic and immunohistochemical investigations revealed different tissue types within the tumor including stromal connective tissue and fusiform mesenchymal cell formations surrounding blastemal cells as well as different developmental stages of organ-specific epithelial cells accompanied by extensive cyst formation. Metastases were not observed. In consideration of the macroscopic, histologic, and immunohistochemical findings, the tumor was classified as a nephroblastoma closely resembling the so-called Wilms' tumor, a malignant embryonic renal tumor frequently observed in humans, especially in young children. In contrast, this tumor entity has rarely been observed in nonhuman primates. This report represents the first documented case of a cystic variant of nephroblastoma in a nonhuman primate.