Cervical spinal cord astrocytoma in a dog

An astrocytoma of the cervical spinal cord was diagnosed in a 3-year-old Siberian Husky. The dog had an 8-week history of progressive neurologic deficits that finally resulted in nonambulatory tetraparesis. Neurologic examination, CSF analysis, myelography, exploratory laminectomy and histopathologic examination were performed. Intramedullary spinal cord tumors such as astrocytomas are rare, and this case illustrates the manner in which spinal cord tumors may be confused with other nervous system diseases, both from a clinical and clinicopathologic standpoint.     

Cervical spinal arachnoid cyst in a dog

An 18-month-old, intact male Akita presented with a 12-month history of progressive ataxia, hypermetria, and loss of conscious proprioception of the thoracic and pelvic limbs. Neurological examination and myelography localized a lesion at cervical vertebrae 1 and 2 consistent with an arachnoid cyst. Hemilaminectomy and cyst fenestration led to virtually full recovery.     

Cervical syringohydromyelia secondary to a brainstem tumor in a dog

An 11-year-old male Pekingese was evaluated because of a history of head tilt. Neurologic examination revealed a right-sided head tilt, ataxia, scoliosis, and proprioceptive deficits. Diagnostic testing included magnetic resonance imaging (MRI) of the head and neck. After IV administration of gadopentetate dimeglumine, an extra-axial, highly contrast-enhanced mass in the brainstem, cerebellar herniation, and syringohydromyelia were detected via MRI. The dog was treated with corticosteroids and radiation therapy of the mass for 4 weeks (total dose, 42.5 Gy). Magnetic resonance imaging was repeated 9 weeks and 6 months after radiation therapy; compared with the initial findings, a reduction in the size of the brainstem mass was observed in both MRI scans. The third MRI scan also revealed a normal cerebellar shape, no evidence of herniation, and resolution of syringohydromyelia in the dog at that time. It is recommended that whenever syringohydromyelia is observed via MRI, a primary cause (cranial or caudal to the affected region) should be sought.     

Cervical spinal chordoma with chondromatous component in a dog

A 7-year-old male Belgian Shepherd dog was presented with sudden onset of lateral recumbency and tetraparesis. At the level of the third cervical vertebra, magnetic resonance imaging demonstrated an intrameningeal and intramedullary mass lesion. The animal was subsequently euthanatized. A necropsy revealed a semitranslucent solid mass infiltrating dorsal and ventral dura mater and the spinal cord. Histologic examination revealed a lobulated pleomorphic mass, mainly resembling undifferentiated cartilage interspersed by spindle-shaped and polygonal cells with highly vacuolated cytoplasm (physaliphorous cells). Immunohistochemistry of the tumor cells demonstrated dual expression of vimentin and cytokeratin. Based on the histologic and immunohistochemical results, the diagnosis of a chordoma with chondromatous component was made.     

Co‐existing monophasic teratoma and uterine adenocarcinoma in a female dog

Ovarian teratomas are occasionally reported in dogs; the rarest type is the monophasic teratoma, composed of tissues originating from only one germ layer. Canine endometrial adenocarcinomas are also rare in dogs and mainly affect geriatric females. This report describes the case of co‐existing ovarian teratoma and uterine adenocarcinoma in a 10‐year‐old nulliparous female Boxer presented with lethargy, anorexia and purulent vaginal discharge. Abdominal ultrasonography evidenced pyometra and a mass in the left ovary. This was composed of a uniform whitish tissue with multiple cystic structures. The histology revealed an atrophy of the ovarian parenchyma, compressed by a proliferation of well‐differentiated nervous tissue staining positively to vimentin, S100 and neuronal specific enolase (NSE), and negatively to keratin and inhibin. The left uterine horn, whose diameter was markedly increased, showed foci of endometrial cellular atypia, evident nucleoli and mitoses, at light microscopy. To our best knowledge, this is the first report of a co‐existing ovarian monophasic teratoma and endometrial adenocarcinoma, two rare reproductive neoplasia in dogs.     

Ovarian teratoma with a formed lens and nonsuppurative inflammation in an old dog

A 9-year, 7-month-old female German shepherd weighing 26.6 kg was admitted to the hospital for pica and diarrhea. A large mass was found in the right ovary and removed, and cross section of the mass revealed a multilobular tumor consisting of several cystic cavities which contained tufts of dark hair in thick creamy-white sebaceous fluid. Histologically, the tumor consisted of adipose tissue, central nervous tissue, crystalline lens, cartilage and bone. In the central nervous tissue, lens and lesions like nonsuppurative inflammation comprizing of accumulation of glial cells and lymphocytic perivascular cuffing were observed. The tumor was diagnosed as a mature cystic teratoma.     

Cervical neoplasia originating from the vagus nerve in a dog

An eight-year-old intact male Bernese mountain dog was referred with a history of chronic vomiting, coughing and signs of respiratory distress. Other historical findings included lethargy, weight loss and choking. On presentation, clinical findings were Horner's syndrome, ipsilateral laryngeal hemiplegia, coughing, gagging, respiratory distress and vomiting. Lateral cervical radiographs showed ill-defined mineralisation in the soft tissue ventral to the third cervical vertebra, while ultrasonography of the neck revealed a well marginated heterogeneous mass with focal hyperechogenic lesions and acoustic shadowing. Results of an ultrasound-guided fine needle aspirate suggested neoplasia. At necropsy, a large tumour was detected in the ventral cervical region, originating from the right vagosympathetic trunk. In view of the infiltrating pattern, the cellular pleomorphism and the numerous mitoses on histopathological examination, the tumour was classified as a malignant peripheral nerve sheath tumour.     

Renal teratoma in a llama

Teratomas are neoplasms of embryonal origin in domestic animals and are generally associated with reproductive organs. We report a case of teratoma involving the right kidney in a young llama that presented clinically with signs of mild colic and constipation.     

Ovarian teratoma in a bitch

An ovarian teratoma in a 5-year-old bitch with a history of vaginal discharge was removed successfully by ovariohysterectomy. The mass was discovered on abdominal palpation and contained multiple mineralized densities that were visualized radiographically. Histologic examination of the mass confirmed the presence of tissues originating from multiple germ-cell layers, characteristic of a teratoma. Clinical findings in dogs with teratomas include abdominal distention, a palpable abdominal mass, and rarely, evidence of reproductive hormonal activity. These neoplasms are uncommon in the dog, and they may exhibit malignant tendencies, with metastasis developing in approximately 33% of the reported cases. Ovariohysterectomy is the preferred treatment for ovarian teratomas, and this procedure was curative in the dog of this report.     

Cervical vertebral instability (wobbler syndrome) in the dog.

Observations on a series of 38 cases (35 Doberman Pinschers and three Great Danes) of the canine wobbler syndrome are described. Radiographic examinations suggested that the primary lesion is an intervertebral instability at C6/7, but with time, secondary changes of the disc degeneration and prolapse and vertebral body malformation causing stenosis of the vertebral canal occur. Cases detected at a young age and showing only the primary lesion were treated successfully, by disc fenestration alone or by disc fenestration and intervertebral screwing. The success rate in older cases with secondary lesions was poor and in this type of case, cord decompression by dorsal laminectomy appears necessary.     

Retrobulbar teratoma causing exophthalmos in a cat

A 3-year female-neutered domestic shorthair cat presenting with exophthalmos and an ipsilateral subzygomatic soft tissue mass lesion is described. Magnetic resonance imaging of the mass was performed followed by complete surgical excision. The mass was determined to be a retrobulbar teratoma and complete resection was curative. Teratomas are rare germ-cell tumours that uncommonly form in extragonadal sites. A retrobulbar location has not been previously reported in the cat and should be considered a rare cause of exophthalmos in this species.     

Ovarian teratoma and endometritis in a mare

An 8-year-old Arabian mare was admitted for a large ovarian anovulatory follicle. A clinical diagnosis of ovarian tumor and endometritis was established. Histological examinations revealed an ovarian teratoma and a grade II endometritis. Three months after unilateral ovariectomy, the mare was confirmed pregnant and eventually gave birth uneventfully.