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.     

Congenital mesoblastic nephroma in a young basset hound dog

An 18‐month‐old male basset hound was presented with vomiting, diarrhoea and depression. Abdominal ultrasonography revealed a mass in the left kidney. An ultrasound‐guided core‐biopsy indicated aggregates of spindle cells, but did not allow a definitive diagnosis. Nephrectomy was performed after a period of six months, when ultrasound examination revealed a slight increase in mass dimensions. Histologically the mass was composed of neoplastic spindle cells forming interlacing fascicles, bundles and whorls, within a loose myxoid to dense collagenous stroma. Immunohistochemically neoplastic cells were positive for vimentin and smooth muscle actin. Based on these findings the tumour was diagnosed as a congenital mesoblastic nephroma, classical variant. After a two‐and‐a‐half‐year follow‐up the dog was clinically healthy, indicating a benign behaviour. To the authors’ knowledge, this report describes the first case of canine congenital mesoblastic nephroma successfully treated surgically, with a reasonable postsurgical follow‐up.     

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.     

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.     

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.     

Spontaneous nephroblastoma in a Japanese giant salamander (Andrias japonicus)

An adult male Japanese giant salamander (Andrias japonicus) died accidentally, and necropsy showed a white mass (23 × 15 mm) in the left kidney and hepatorrhexis with hemoperitoneum. Histologically, the renal mass was mainly composed of immature nephroblastic tumor cells. In the tumor tissue, a trabecular pattern lined by oval to polygonal tumor cells with a rich interstitium, solid growth and a few tubular structures was observed. Nephroblastic tumor cells were strongly positive for vimentin and weakly positive, and epithelium-like tumor cells were strongly positive for cytokeratin. However, antibody for Wilms' tumor protein 1 did not react with the salamander's cells. On electron microscopy, a desmosome junction was observed between tumor cells. This is the first report of nephroblastoma in a Japanese giant salamander.     

Renal embryonal nephroma exhibiting malignant features in a Dutch rabbit (Oryctolagus cuniculus)

BackgroundBenign embryonal nephromas have been documented in rabbits. However, only one case of nephroblastoma with concurrent metastasis (pulmonary), a postmortem incidental finding, has been published.Case presentationA 3-year-old neutered male Dutch rabbit (Oryctolagus cuniculus) was referred for assessment of a firm mass located in the mid-dorsal abdomen. Abdominal ultrasonography confirmed a large soft tissue mass of suspected renal origin. A left-sided nephrectomy was performed via a ventral midline approach. Multiple white macular lesions, hyperemia, and petechiae were observed in the mesenteric fat surrounding the spleen. Histopathological examination of the abnormal kidney and the mesenteric fat revealed microscopic findings consistent with an embryonal nephroma exhibiting distinct features of malignancy. At 6- and 12-month postsurgery, ultrasonographic evidence of tumor recurrence was not observed.Conclusion and case relevanceThis is the first report of successful treatment of an embryonal nephroma showing malignant behavior and metastasis to the surrounding adipose tissue with a minimum postoperative survival time of 12 months and no ultrasonographic evidence of local recurrence.     

Oslerus (Filaroides) osleri in a dog

A young female Queensland Blue Heeler with signs of severe respiratory distress was diagnosed as having Oslerus osleri. Radiographic, bronchoscopic, parasitologic and pathologic findings are described and treatment is briefly reviewed. A possible route of larval migration from the pulmonary capillaries to the predilection site is proposed.     

SOMA (carisoprodol) toxicity in a dog

Objective: To describe a case of SOMA intoxication in a dog. Case summary: A 13‐year‐old, 25 kg, female spayed Australian shepherd presented to the emergency service after ingestion of ten to fifteen 350 mg tablets of SOMA (carisoprodol), a muscle relaxant used for back pain in humans. Toxic effects of the drug in this dog included mild sinus tachycardia, respiratory depression, seizures, and ataxia. The dog's mentation progressively deteriorated from depressed to comatose within 1 hour after admission. Treatment on initial presentation consisted of induction of emesis while the dog still had a gag reflex, administration of activated charcoal, oxygen therapy, and supportive care. The dog was discharged to the owner prior to full recovery (4 days later). New or unique information provided: This is the first known report of carisoprodol intoxication in the dog.     

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.