Diagnosing appendicular osteosarcoma with ultrasound-guided fine-needle aspiration: 36 cases

OBJECTIVES

To determine the ability to obtain diagnostic cytology samples from appendicular bone lesions using ultrasound-guided needle aspirations. Secondary objectives were to compare cytological evaluations with histopathological results and to determine the utility of staining malignant mesenchymal cells for the presence of alkaline phosphatase.

METHODS

Aspirations from 36 aggressive appendicular bone lesions with histological diagnoses were included in the study. Ultrasound was used to guide the needle to the medullary cavity or the adjacent soft tissue mass. The smears stained with Wright-Giemsa and nitroblue tetrazolium chloride/5-bromo-4-chloro-3-indoyl phosphate toluidine salt (NBT/BCIP) were examined.

RESULTS

A diagnostic sample was obtained in 32 of the 36 cases. Of the 32 diagnostic samples, cytology indicated sarcoma, with a sensitivity of 97 per cent (confidence interval: 83 to 100 per cent) and a specificity of 100 per cent (confidence interval: 16 to 100 per cent). When a diagnosis of sarcoma was made on cytology, alkaline phosphatase staining indicated osteosarcoma, with a sensitivity of 100 per cent (confidence interval: 87 to 100 per cent).

CLINICAL SIGNIFICANCE

The results of this study indicate that ultrasound-guided needle aspiration of aggressive bone lesions is a viable technique for identifying malignant mesenchymal cells and for diagnosing sarcomas. It is cost-effective and minimally invasive. Furthermore, identifying alkaline-phosphatase-negative malignant mesenchymal cells from a bone aspiration may rule out osteosarcoma, whereas alkaline-phosphatase-positive malignant mesenchymal cells are suggestive of osteosarcoma.

Results of craniotomy for the treatment of cerebral meningioma in 42 cats

Forty-two cats underwent craniotomy for removal of a meningioma between 1985 and 1991. Median duration of clinical signs before examination was 1.25 months. All cats had inappropriate demeanor: 48% were dull and 38% were lethargic. Neurological deficits included impaired vision in 93%, paresis in 83%, and seizures in 19%. Computed tomography (CT) showed solitary masses in 86% and multiple masses in 14%. Intraoperative complications included hemorrhage and difficulty excising deep or adherent masses. Anemia in 13 of 42 cats was the most common immediate postoperative complication. Ten of 42 cats had no improvement or a more severe neurological status after surgery. Eight of 42 cats died immediately after surgery; 6 of these were anemic. Of the cats that survived the immediate postoperative period, evaluation 10 to 14 days after surgery showed that 97% (33 of 34) were alert and 79% (27 of 34) had returned to normal behavior. Neurological deficits, except for vision impairment, had resolved in most cats. The duration of follow-up varied from 1.3 months to 55.1 months. Ten cats developed neurological abnormalities from 1 month to 44.2 months after surgery; of these, 6 had tumor recurrence or new growth confirmed by CT scan or necropsy. Overall survival was 71% at 6 months, 66% at 1 year, and 50% at 2 years. Age of cat and location of tumor did not significantly affect survival (P = .1034 and .1851, respectively). There were too few precise measurements of tumor size to make a valid statistical comparison of the effect of size on survival. Location or presence of multiple tumors did not affect final outcome.(ABSTRACT TRUNCATED AT 250 WORDS)

High-rise syndrome in dogs: 81 cases (1985-1991)

We evaluated 81 dogs with high-rise syndrome. Dogs fell from 1 to 6 stories, and of 52 dogs for which the fall was witnessed, 39 had (75%) jumped. Dogs sustained a triad of injuries to the face, thorax, and extremities, similar to injuries seen in cats with high-rise syndrome, but with differences in degree and distribution. Height fallen and landing surface affected initial status and type and severity of injury. Cause of fall influenced distribution of extremity injury. Dogs falling < 3 stories had a high prevalence of extremity fractures. Higher falls resulted in more spinal injuries. We recommend initial treatment for shock and thoracic trauma followed by orthopedic and neurologic evaluation. Visceral trauma should be considered if response to emergency treatment is poor. All but 1 of the dogs survived.

Case report 673: Telangiectic osteogenic sarcoma

A case is presented of a telangiectatic osteogenic sarcoma involving the left third metatarsal of a 4-year-old male Great Dane dog. Radiographs revealed a diaphyseal, expanding, lytic lesion with minimal intralesional sclerosis and a sclerotic rim in the proximal portion. The lesion contained a large amount of blood. The biopsy specimens consisted of spaces which were outlined by fibrous osteoid or granulation tissue. There were islands of multinuclear giant cells and/or fibrous osteoid tissue. A diagnosis of aneurysmal bone cyst was made. The lesion was treated by curettage and insertion of cancellous bone graft but was progressive 10 weeks after treatment. The lesion was further curetted, and these biopsy specimens consisted of aneurysmally dilated spaces and areas of anaplastic sarcomatous cells with mitotic figures and osteoid production, characteristic of telangiectatic osteogenic sarcoma. The dog was euthanized as the owner requested; an autopsy was not performed.

Case report 622. Multiple cartilaginous exostoses

The case is presented of multiple cartilaginous exostoses involving the right and left metatarsals and phalanges, left scapula, ends of several distal ribs, and the spinous processes of several thoracic and lumbar vertebrae in a 3-month-old female Scottish terrier dog. Radiographical studies showed circumscribed expansile lesions in the affected bones. The dog developed neurological deficits 3 weeks later. Myelography displayed extradural compression of the opaque column at several thoracolumbar vertebrae. The biopsy specimen from an affected phalanx consisted of trabecular bone and hemopoietic tissue covered by a thin cap of hyaline cartilage. The dog was euthanized due to the poor prognosis. At autopsy, the surface of the affected bones was covered by a bluish-white, smooth, undulating cartilage cap. Histopathologically, the cartilaginous cap consisted of hyaline cartilage without a reserve zone, and abnormal endochondral ossification. The hereditary nature and the malignant transformation of multiple cartilaginous exostoses in the dog have been considered.

Problems with owner communications

This chapter deals with communication problems between the veterinary surgeon and the owners of animals undergoing treatment for intervertebral disc disease, an area that has often been neglected in other works that usually deal exclusively with pathophysiology, diagnosis, and treatment. Neurologic disease can be a confusing subject, especially for the untrained owner of an afflicted animal and many areas of potential confusion between the veterinarian and the owner can occur. Potential problems may arise during the discussion of the medical history, interpretation of the neurologic examination, explanation of differential diagnostic and treatment alternatives, and description of the operative and postoperative phases. Each of these areas is discussed relative to the veterinarian's interaction with the owner of the animal patient.

Osteosarcoma of the patella in a dog

Osteosarcoma of the patella was diagnosed by biopsy in a 9-year-old, male dog of mixed breeding. The dog was originally examined because of intermittent lameness of the left hindlimb; there were minimal palpable abnormalities of the stifle. After the diagnosis, the owner refused further treatment for the dog. The dog was reexamined 13 months later because of a marked swelling of the stifle. The dog was euthanatized and necropsy findings confirmed the diagnosis.

Vulvar and vaginal tumors in the dog: a retrospective study

Vulvar or vaginal neoplasia was diagnosed in 99 dogs. The most common clinical sign was vulvar discharge or the sudden appearance of a protruding mass from the vulva. Most of the dogs were old (average age, 10.8 years) and sexually intact. Of the 99 tumors, 72 were benign, 17 were malignant, and 10 were transmissible venereal tumors. Except for the transmissible venereal tumors, most tumors were of smooth muscle or fibrous tissue origin (leiomyoma, fibroma, and leiomyosarcoma). In the dogs with benign tumors, surgical excision of the tumor combined with ovariohysterectomy was effective in preventing recurrence of disease.