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
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
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;
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.
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.
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.
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.
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.
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.
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.