Amiya K. Patnaik

Spinal tumors in 37 dogs: clinical outcome and long-term survival (1987-1994).

The current management of dogs with spinal canal neoplasia in a large veterinary institution was evaluated. Postoperative survival time and prognostic indicators for survival were examined. Spinal neoplasms in dogs and humans also were compared. Thirty-seven cases with histologically confirmed spinal tumors were included in the study. The cervical region was affected most commonly, and 23 (62%) of 37 cases had extradural tumors. A hemilaminectomy or a dorsal laminectomy was performed in each case; three cases received adjuvant treatment. Twelve (32%) cases were euthanized at the time of surgery, and two died immediately after surgery. One dog was euthanized 20 days after surgery because of persistent clinical signs. Twenty-two cases were followed postoperatively; nine different types of primary tumors were confirmed by histological examination of tissue specimens from these 22 cases, and three cases had metastatic lesions. The median survival time of these 22 cases was 240 days. Twelve (32%) of the 37 cases had nerve-sheath tumors; the median survival time for these 12 cases was 180 days. No prognostic indicators were identified. However, median survival times of cases with benign versus malignant tumor types were 1,410 days and 180 days, respectively (p of 0.07). Four cases each had a myxoma/myxosarcoma, a tumor previously unreported in the spinal canal in dogs.

Prognostic Factors in Dogs with Urinary Bladder Carcinoma

Medical records and biopsy specimens were retrospectively reviewed from 25 dogs diagnosed with unresectable urinary bladder carcinoma and treated with chemotherapy. Our intention was to identify clinical, histologic, and immunohistochemical indicators of prognosis. Immunohistochemical stains for P-glycoprotein, glutathione-S-transferase pi, and factor VIII-related antigen were applied to archived tissue. There were more spayed female dogs than castrated male dogs (76% versus 24%). Transitional cell carcinoma was the most common tumor (88%, n = 22), followed by undifferentiated carcinoma (8%, n = 2) and squamous cell carcinoma (4%, n = 1). Overall median survival was 251 days. Histologic diagnosis and immunohistochemical characteristics did not correlate with prognosis. Spayed females survived significantly longer than castrated males (358 days versus 145 days, P = .042). Dogs that received either doxorubicin or mitoxantrone in addition to a platinum-based chemotherapeutic (either cisplatin or carboplatin) lived significantly longer than those that received only a platinum compound (358 days versus 132 days, P = .042).

Hepatobiliary neuroendocrine carcinoma in cats: a clinicopathologic, immunohistochemical, and ultrastructural study of 17 cases.

Hepatobiliary neuroendocrine carcinoma was diagnosed in 17 cats in a period of 10 years. Seven tumors were of intrahepatic origin, one of which was a composite containing components of epithelial and neuroendocrine carcinoma. Nine tumors were of extrahepatic origin, and one tumor was located in the gallbladder The cats were adult and geriatric, and the male: female ratio varied according to tumor group. Hepatomegaly, anorexia, weight loss, and vomiting were the most common clinical signs observed in the cats with hepatic neuroendocrine carcinoma. The cats with extrahepatic neuroendocrine carcinoma showed these signs plus icterus (5/9) and high concentrations of hepatic enzymes. Histologically, the hepatic neuroendocrine carcinomas had two patterns, one with acinar structures separated by vascular stroma lined by cuboidal or columnar cells and the other solid with groups of anaplastic cells separated by vascular stroma. The composite tumor consisted of both bile duct carcinoma and neuroendocrine carcinoma. The extrahepatic neuroendocrine carcinomas and the gallbladder neuroendocrine carcinoma were characterized by solid sheets or groups of round to oval cells with vascular or fibrovascular stroma. Immunohistochemical examination of 10 of the neuroendocrine carcinomas revealed that all 10 stained with neuron-specific enolase; one bile duct carcinoma and the gallbladder carcinoma stained with chromogranin; four of five bile duct carcinomas and the gall bladder carcinoma stained with synaptophysin; and one bile duct carcinoma stained with gastrin. one cat with hepatic carcinoma had duodenal ulcer; in this cat, ultrastructural studies showed neurosecretory granules leading to the diagnosis of Zollinger-Ellison syndrome. In four cats in which necropsy was permitted, carcinomatosis (4/4), lymph nodes (4/4), lungs (2/4), and intestines (1/4) were the metastatic sites. Fourteen of the 17 cats were euthanatized during or immediately after surgery.

Canine Hepatic Neuroendocrine Carcinoma: An Immunohistochemical and Electron Microscopic Study

Ten dogs with neuroendocrine carcinoma of the liver were selected for inclusion in the study. Clinical signs were anorexia (7), vomiting (5), polydipsia/polyuria (3), icterus (2), lethargy (2), weight loss (2), paresis (1), ataxia (1), weakness (1), collapse (1), and urinary tract infection (1). Hematologic and biochemical abnormalities included anemia (2/8), leukocytosis (4/8), high liver enzyme activity (serum alkaline phosphatase, 7/9; alanine transaminase, 7/9; aspartate transaminase, 8/9), and high total bilirubin (6/9). Grossly, the tumors were diffuse, involving all liver lobes in six dogs, and two dogs had various-sized nodules in addition to diffuse involvement. Histologically, there were eight tumors with solid or trabecular pattern (group A), one tumor with cords or rows of neoplastic cells (group B), and one tumor with multiple rosette-like structures (group C). immunohistochemical studies revealed that all 10 neoplasms were positive for at least one of the endocrine markers used: neuron-specific enolase (NSE; 8/10), synaptophysin (5/10), and chromogranin-A (3/10). A panel of NSE, chromagranin-A, and synaptophysin detected 100% of the tumors in our series. Electron microscopy confirmed the diagnosis by the presence of intracytoplasmic neurosecretory granules in the two examined cases. our results show that neuroendocrine markers commonly used in humans can be used for the diagnosis of hepatic neuroendocrine carcinoma in dogs, preferably a panel of synaptophysin, chromagranin-A, and NSE because chromogranin-A alone is not as useful in dogs as in humans.

Efficacy of Cobalt-60 Radiation Therapy for the Treatment of Nasal Cavity Nonkeratinizing Squamous Cell Carcinoma in the Dog

The purposes of this study were to evaluate the efficacy of cobalt-60 radiotherapy in the treatment of nonkeratinizing squamous cell carcinoma of the nasal cavity in dogs and to compare this treatment group to historical controls. Six dogs with histopathologically confirmed nasal cavity nonkeratinizing squamous cell carcinoma were treated with cobalt-60 radiotherapy to a total dose of either 63 Gy or 54 Gy. Overall survival times ranged from 30 days to 330 days, with a median survival time of 165 days. Nasal cavity nonkeratinizing squamous cell carcinoma in the dog is an aggressive tumor that responds poorly to radiotherapy.

Malignant Ovarian Teratoma in a Red-Eared Slider (Trachemys Scripta Elegans):

A 7-year-old intact female red-eared slider (Trachemys scripta elegans) presented with anorexia of 2–3-weeks duration. Coelomic radiographs demonstrated 3 shelled eggs in the right cavity. Hormone therapy failed to induce oviposition. Exploratory laparotomy revealed 3 calcified eggs in the right oviduct and a large mass obliterating the left ovary. The large, multilobulate mass had scattered, firm, white nodules and weighed 450 g. Histopathology revealed a malignant teratoma composed of immature embryonal and extraembryonal elements derived from all 3 germ layers with multifocal epithelial anaplasia. This is the first report of a teratoma in chelonian gonadal tissue. Teratomas and reptilian gonadal neoplasia are reviewed.