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  • Author or Editor: Elizabeth A. McNiel x
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Abstract

Objective—To establish an immortalized cell line and transplantable xenograft of feline bronchioloalveolar lung carcinoma (BAC).

Sample Population—Pleural effusion from a 12-yearold Persian male cat with BAC.

Procedure—Tumor cells from the pleural effusion were grown in monolayer cell culture and injected into severe combined immunodeficient (SCID) mice to establish an immortalized cell line as well as a transplantable xenograft.

Results—Both the primary lung carcinoma, the derived cell line, and the transplantable xenograft had evidence of a type-II pneumocyte origin expressing lamellar bodies ultrastructurally and thyroid transcription factor-1 and surfactant immunocytochemically. All 3 also expressed nuclear p53 immunoreactivity. A metaphase spread of the cell line (SPARKY) probed with fluorescein-labeled genomic feline DNA gave evidence of its feline origin. Flow cytometric studies indicated aneuploidy with a DNA index of 1.6. An R-banded karyotype revealed a modal number of 66 including the feline Y chromosome. The cell line had a doubling time of 16 hours. The xenograft (SPARKY-X) reached a diameter of 1 cm in 3 weeks in SCID mice. Deoxyribonucleic acid fingerprint analysis revealed that SPARKY and SPARKY-X were novel and strongly matched each other, except for the murine component found in SPARKY-X. Interestingly, SPARKY-X manifested the characteristic lepidic growth pattern of pulmonic BAC.

Conclusions—Both the cell line and xenograft retained their autochthonous BAC phenotype, making them useful for the subsequent dissection of molecular abnormalities in feline BAC and in vitro screening of chemotherapeutic agents. (Am J Vet Res 2002; 63:1745–1753)

Full access
in American Journal of Veterinary Research

Abstract

Case Description—A 9-year-old spayed female mixed-breed dog was evaluated because of a progressively worsening, nonproductive cough and gagging of 1 year's duration.

Clinical Findings—Physical examination results were unremarkable. A cranial mediastinal mass was identified at the heart base with 3-view thoracic radiography. A CT scan of the thorax revealed an invasive mass surrounding major vessels at the heart base that was not considered surgically resectable. Thoracoscopic biopsy specimens of the cranial mediastinal mass were obtained, and histologic evaluation revealed that the tumor was a chemodectoma.

Treatment and Outcome—On the basis of results of the CT scan, a 3-D conformal radiation therapy plan was generated with computer treatment-planning software. The patient was treated with external beam radiation therapy; a 6-MV linear accelerator was used to deliver a prescribed dose of 57.5 Gy in twenty-three 2.5-Gy fractions. The cough improved following radiation therapy. Prior to treatment, the tumor volume was calculated to be 126.69 cm3. Twenty-five months following radiation therapy, a follow-up CT scan was performed and there was a >50% reduction in tumor volume at that time. Disease progression causing pericardial, pleural, and peritoneal effusion and syncopal episodes occurred 32 months following radiation therapy, which were treated with pericardectomy and additional radiation therapy. The dog was still alive and doing well 42 months following initial radiation treatment.

Clinical Relevance—Conformal radiation therapy provided an additional treatment option for a nonresectable heart base chemodectoma in the dog of this report; conformal radiation therapy was reasonably tolerable and safe.

Full access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To evaluate the use of urinary biomarkers to assess exposure of cats to environmental tobacco smoke (ETS).

Animals—61 healthy client-owned cats (19 from households in which smoking was reported and 42 from households in which there was no smoking).

Procedures—Urine samples were obtained from each cat and assayed for total nicotine (nicotine plus nicotine glucuronide) and total cotinine (cotinine plus cotinine glucuronide) content by use of gas chromatography-mass spectrometry. In addition, total urinary content of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), a major metabolite of the tobacco-specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone, was measured by use of gas chromatography with nitrosamine-selective detection.

Results—Cats from households in which smoking was reported had significantly higher concentrations of total nicotine (70.4 ng/mL), total cotinine (8.53 ng/mL), and total NNAL (0.0562 pmol/mL) in urine, compared with concentrations for cats that lived in households in which there was no smoking (4.89 ng/mL, 0.74 ng/mL, and 0.0182 pmol/mL, respectively).

Conclusions and Clinical Relevance—Analysis of these data provided biochemical evidence of exposure to ETS and uptake of tobacco-specific carcinogens by cats that live in households with smokers. Biomarkers could facilitate investigation of the health effects of ETS in cats and other species.

Full access
in American Journal of Veterinary Research

Abstract

Objective—To evaluate changes in serial hemograms and serum biochemical profiles in tumor-bearing dogs undergoing daily anesthesia with propofol as an induction agent for radiation therapy.

Design—Retrospective case series.

Animals—31 dogs with cutaneous or subcutaneous malignancies over the trunk or limbs.

Procedures—Radiation therapy consisted of 18 daily treatments administered Monday through Friday over a period of 24 days. Propofol was administered IV to effect for induction of anesthesia. Complete blood count and serum biochemical data were generated at the beginning, middle, and end of radiation therapy and compared to identify changes over time via either a repeated-measures ANOVA or Friedman test.

Results—Leukocyte and platelet parameters did not differ significantly over time. Calculated Hct, erythrocyte count, hemoglobin concentration, and mean corpuscular hemoglobin concentration decreased overtime, whereas mean corpuscular volume increased overtime.

Conclusions and Clinical Relevance—Dogs receiving propofol for induction of anesthesia and radiation therapy had a decrease in RBC count, although these changes were not determined to be of clinical importance in this patient population. The cause of these alterations was not immediately apparent. Propofol appeared to be a safe choice for induction of anesthesia in dogs during daily radiation therapy.

Full access
in Journal of the American Veterinary Medical Association

Objective

To determine associations between clinical and histologic factors in dogs with primary lung tumors and outcome and to develop a histologic grading method for primary lung tumors.

Design

Retrospective study.

Animals

67 dogs undergoing thoracotomy and lobectomy for primary lung tumors.

Procedure

Medical records and histologic sections were reviewed to evaluate factors of prognostic importance. Association of these factors with disease-free interval (DFI) and survival time was evaluated, using the Cox proportional hazards model. Median DFI and survival time were determined, using the Kaplan-Meier product-limit method.

Results

Clinical and histologic factors significantly associated with prognosis were histologic score, detection of clinical signs, and metastasis to regional lymph nodes. On the basis of histologic score, a histologic grading method was developed. Dogs with well-differentiated tumors had significantly longer survival time and DFI (median DFI, 493 days) than dogs with moderately (median DFI, 191 days) or poorly (median DFI, 0 days) differentiated tumors. Dogs with clinical signs or metastasis to regional lymph nodes had shorter survival times and DFI than dogs in which lung masses were discovered as an incidental finding.

Clinical Implications

Dogs with well-differentiated, nonmetastasized, primary lung tumors that do not have clinical signs associated with the tumor have a favorable prognosis. Dogs with more advanced disease or aggressive tumors histologically may require treatment, such as chemotherapy in combination with surgery. The grading method proposed here for primary lung tumors may be useful in other dogs with primary lung tumors. (J Am Vet Med Assoc 1997;211:1422–1427)

Free access
in Journal of the American Veterinary Medical Association

Objective

To determine the effectiveness and safety of asparaginase administered SC versus IM for treatment of multicentric lymphoma in dogs receiving doxorubicin.

Design

Prospective study.

Animals

49 dogs with multicentric lymphoma

Procedure

Dogs were treated with doxorubicin every 3 weeks, for a total of 5 treatments, and were given 3 weekly treatments of asparaginase, SC or IM. Using high-performance liquid chromatography, mean plasma asparagine, aspartic acid, glutamine, and glutamic acid concentrations were determined in dogs before and during treatment with asparaginase (10,000 U/m2 of body surface area, once a week for 3 weeks). Asparaginase was administered SC in 23 dogs and IM in 26 dogs. Variables evaluated included time to response to chemotherapy, remission and survival times, and clinical and serum biochemical indicators of toxicoses

Results

Using the World Health Organization's staging system for lymphoma, 30 dogs were in clinical stage III and 19 were in clinical stage IV. One week after asparaginase treatment, plasma asparagine concentrations were low and plasma aspartic acid, glutamine, and glutamic acid concentrations were high. Differences in plasma amino acid concentrations were not found between SC and IM groups. For dogs in clinical stage IV, IM administration of asparaginase significantly decreased the number of days to complete remission, compared with SC administration (8 vs 17 days, respectively). For dogs in clinical stage III, IM administration favorably increased the duration of first remission (191 vs 103 days) and survival time (289 vs 209 days). Overall, dogs treated IM had a faster response to chemotherapy (9 vs 15 days), a longer remission (191 vs 109 days), and a longer survival time (286 vs 198 days), compared with all dogs treated SC. Asparaginase toxicoses were not observed regardless of the route of administration.

Clinical Implications

For dogs with multicentric lymphoma that are receiving doxorubicin, IM treatment with asparaginase is more effective than SC treatment. (J Am Vet Med Assoc 1999;214:353–356)

Free access
in Journal of the American Veterinary Medical Association

Abstract

CASE DESCRIPTION

A 25-year-old 4.4-kg male aquarium-hatched African penguin (Spheniscus demersus) was evaluated because of a raised 1.5 × 0.5-cm pigmented mass extending from within the right naris noted 2 days earlier.

CLINICAL FINDINGS

The penguin had a raised pigmented mass extending out from the right naris and onto the upper beak. Histologic examination of excisional biopsy specimens confirmed a diagnosis of malignant melanoma. A treatment plan including administration of meloxicam, radiation therapy, and immunotherapy was initiated.

TREATMENT AND OUTCOME

Treatment with meloxicam (0.2 mg/kg, PO, q 24 h) was initiated and continued for a total of 45 weeks; however, the medication was discontinued for a period of 6 weeks because of the risk of toxic effects in the chick that the penguin was feeding at that time. The penguin underwent local hypofractionated radiation therapy and received 4 once weekly 8-Gy fractions of radiation (total radiation dose, 32 Gy). The penguin was administered a canine melanoma vaccine transdermally every other week for 4 doses, with a booster injection given 7 months after the first dose. Treatment with the vaccine appeared to have no adverse effects. The penguin’s pre- and postvaccination tyrosinase-specific antibody titers were measured with an anti–human tyrosinase-specific ELISA, and a 3-fold titer increase indicated a positive humoral immune response to the canine melanoma vaccination. The penguin died of unrelated causes 54 weeks after initial diagnosis, and there was no evidence of metastasis on necropsy.

CLINICAL RELEVANCE

These case findings suggested that vaccination with a canine melanoma vaccine may be a safe and useful adjunct treatment for management of malignant melanoma in penguins.

Full access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To evaluate factors associated with survival in dogs with nasal carcinomas that did not receive treatment or received only palliative treatment.

Design—Retrospective case series.

Animals—139 dogs with histologically confirmed nasal carcinomas.

Procedures—Medical records, computed tomography images, and biopsy specimens of nasal carcinomas were reviewed. Only dogs that were not treated with radiation, surgery, chemotherapy, or immunotherapy and that survived ≥ 7 days from the date of diagnosis were included. The Kaplan-Meier method was used to estimate survival time. Factors potentially associated with survival were compared by use of log-rank and Wilcoxon rank sum tests. Multivariable survival analysis was performed by use of the Cox proportional hazards regression model.

Results—Overall median survival time was 95 days (95% confidence interval [CI], 73 to 113 days; range, 7 to 1,114 days). In dogs with epistaxis, the hazard of dying was 2.3 times that of dogs that did not have epistaxis. Median survival time of 107 dogs with epistaxis was 88 days (95% CI, 65 to 106 days) and that of 32 dogs without epistaxis was 224 days (95% CI, 54 to 467 days).

Conclusions and Clinical Relevance—The prognosis of dogs with untreated nasal carcinomas is poor. Treatment strategies to improve outcome should be pursued.

Full access
in Journal of the American Veterinary Medical Association