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  • Author or Editor: Bruce R. Madewell x
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Summary

Sites, histologic types, and frequencies of neoplasms in immature dogs (≤6 months old) were evaluated from data collected over 25 years. The frequencies of neoplasms in immature dogs were compared with those of mature dogs (>6 months old).

Of 69 immature dogs with neoplasms, 5 had 2 primary neoplasms each, resulting in a total of 74 neoplasms. The 3 most common sites for neoplasia, in decreasing order, were the hematopoietic system, brain, and skin. Immature dogs were 10.9 times more likely to have a neoplasm located in the brain, compared with mature dogs. Immature dogs also were 3.3 times more likely to have a neoplasm associated with the hematopoietic system, compared with mature dogs.

Free access
in Journal of the American Veterinary Medical Association

Objective

To describe diseases, prognosis, and clinical outcomes associated with leukocytosis and neutrophilia in dogs.

Design

Retrospective study.

Animals

118 dogs with leukocytosis and neutrophilia.

Procedure

Medical records from 1996 to 1998 were examined for dogs with WBC ≥ 50,000 cells/μl and neutrophilia ≥ 50%. Signalment, absolute and differential WBC counts, body temperature, clinical or pathologic diagnosis, duration and cost of hospitalization, and survival time were reviewed.

Results

Mean age was 7.7 years, WBC count was 65,795 cells/μl, and absolute neutrophil count was 53,798 cells/μI. Mean duration of hospitalization was 7.4 days and cost of hospitalization was $2,028.00. Forty (34%) dogs were febrile, and 73 (62%) dogs died. Overall median survival time was 17 days. Dogs with neoplasia or fever were more likely to die than dogs that were hospitalized or had systemic or local infections.

Clinical Implications

Leukocytosis and neutrophilia were associated with high mortality rate and have prognostic value. Given the mean duration and cost of hospitalization, frank discussion with an owner at first recognition of leukocytosis and neutrophilia may be warranted. (J Am Vet Med Assoc 1999;214:805–807)

Free access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To describe diseases, prognosis, and clinical outcomes associated with extreme neutrophilic leukocytosis in cats.

Design—Retrospective study.

Animals—104 cats with extreme neutrophilic leukocytosis.

Procedure—Medical records from 1991 to 1999 were examined to identify cats that had ≥ 50,000 WBC/µl with ≥ 50% neutrophils. Signalment, absolute and differential WBC counts, rectal temperature, clinical or pathologic diagnosis, duration and cost of hospitalization, and survival time were reviewed.

Results—Mean age of cats was 8.3 years, mean WBC count was 73,055 cells/µl, and mean absolute neutrophil count was 59,046 cells/µl. Mean duration of hospitalization was 5.9 days, and mean cost of hospitalization was $2,010. Twenty-nine (28%) cats were febrile, and 63 (61%) cats died. Overall median survival time was 30 days. Cats with neoplasia were nearly 14 times as likely to die unexpectedly as cats with other diseases.

Conclusions and Clinical Relevance—Extreme neutrophilic leukocytosis was associated with a high mortality rate. The prognostic importance of extreme neutrophilic leukocytosis should not be overlooked. Cats and dogs have similar diseases, mortality rates, and treatment costs associated with extreme neutrophilic leukocytosis. (J Am Vet Med Assoc 2001;218:736–739)

Full access
in Journal of the American Veterinary Medical Association

Abstract

Objective

To develop a slow-release carboplatin formulation for intratumoral administration to cats.

Design

Preliminary study to analyze pharmacokinetic effects of purified sesame oil in the carboplatin formulation for intratumoral administration, and a second study to evaluate the efficacy and toxicosis of intratumoral administration of carboplatin in purified sesame oil.

Animals

23 cats with squamous cell carcinomas of the nasal plane.

Procedure

Eight cats with advanced-stage tumors were submitted to intratumoral administration of 100 mg of carboplatin/m2 of body surface area, with or without purified sesame oil, using a two-period, cross-over design. Fifteen additional cats were treated by intratumoral administration of carboplatin in purified sesame oil. Four weekly intratumoral chemotherapy injections of carboplatin in purified sesame oil at a dosage of 1.5 mg/cm3 of tissue were given.

Results

Purified sesame oil in the formulation significantly reduced systemic exposure to carboplatin and drug leakage from the sites of injection. Cumulative effects of repeated intratumoral administrations on plasma concentrations of carboplatin were not observed. Systemic toxicosis was not observed, and local toxicosis was minimal. Healing of ulcerated lesions was not compromised. Rates of complete clinical tumor clearance and complete response were 67 and 73.3%, respectively. Product-limit estimates of mean progression-free survival times was 16 ± 3.3 months. The 1-year progression-free survival rate was 55.1 ± 13%. Local recurrence was observed in 7 cats; 4 had marginal tumor recurrence, and 3 had in-field and marginal tumor recurrence.

Conclusions

Intratumoral carboplatin chemotherapy is safe and effective for cats with squamous cell carcinoma of the nasal plane. Future studies to improve treatment efficacy could include evaluation of increased dose-intensity as well as combination of this modality with radiotherapy.

Clinical Relevance

Intratumoral administration of carboplatin in a water-sesame-oil emulsion was found to be a practical and effective new treatment for facial squamous cell carcinomas in cats.

Free access
in American Journal of Veterinary Research

Objective

To determine quality and duration of progression-free survival (PFS) time in dogs with malignant oral tumors after definitive megavoltage irradiation, to analyze prognostic factors for PFS time and patterns of failure, and to analyze the influence of tumor recurrence and development of metastasis on survival.

Design

Prospective clinical trial.

Animals

105 dogs with squamous cell carcinoma, fibrosarcoma, or malignant melanoma of the oral cavity without evidence of metastasis.

Procedure

Dogs were treated with 48 Gy over 4 weeks on an alternate-day schedule of 4 Gy/fraction. Multivariate analysis was done by use of Cox's regression model to determine significant prognostic factors and by use of a competing risk model to determine the differential effects of prognostic factors on type of, and time to, failure. In 8% of the dogs, severe acute radiation reactions in the final week of treatment resulted in treatment discontinuation. In 7.6% of the dogs, chronic radiation reactions, including bone necrosis and fistula formation, developed.

Results

Prognostic factors that independently affected PFS time were histologic type and tumor T stage. Histologic type significantly influenced pattern of failure, but not time to failure, whereas clinical stage significantly influenced time to failure, but not type of failure.

Clinical Implications

Irradiation was a safe and effective treatment of malignant oral tumors. Because the local efficacy of radiation was influenced only by tumor size, early treatment of oral tumors should improve the prognosis. In dogs without tumor recurrence, systemic metastases, rather than regional metastases, limited long-term survival after radiation therapy. (J Am Vet Med Assoc 1997;210:778–784

Free access
in Journal of the American Veterinary Medical Association

Summary

Sixteen dogs, given adjuvant cisplatin chemotherapy after amputation for osteogenic sarcoma of the appendicular skeleton, had a median survival time of 413 days. Ten dogs (62%) were alive 1 year after amputation. Dogs were given cisplatin at a dosage of 50 mg/m2 of body surface every 4 weeks for a total of 6 cisplatin treatments, or until metastatic disease was detected. Cisplatin chemotherapy was well-tolerated by most dogs, with only 1 dog developing serious gastrointestinal toxicosis, requiring hospitalization. Results of this study support other investigators' findings that when a cisplatin chemotherapy-based protocol is administered, survival times after amputation can be prolonged for dogs with osteogenic sarcoma.

Free access
in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association

Objective

To determine clinical and pathologic findings in cats with alimentary malignant lymphoma and results of treatment with a combination of prednisone, l-asparaginase, vincristine, cyclophosphamide, doxorubicin, and methotrexate.

Design

Retrospective study.

Animals

21 cats with alimentary malignant lymphoma.

Procedure

Medical records were reviewed, and information on signalment, clinical history and signs, previous treatments, and results of laboratory tests, thoracic radiography, and abdominal ultrasonography were obtained.

Results

Test results in all cats were negative for FeLV; 3 of 19 were positive for feline immunodeficiency virus. Thirteen tumors were stage III, 7 were stage IV, and 1 was stage V. Diagnosis was confirmed on the basis of microscopic examination of histologic (n = 13) or cytologic (8) specimens. Immunophenotyping was performed on 13 tumors; 10 were T-cell and 3 were B-cell lymphomas. Overall median duration of first remission was 20 weeks. Overall median survival time was 40 weeks. The only factor significantly associated with duration of first remission was whether cats had a complete response following induction chemotherapy; duration of first remission was significantly associated with survival time. Cats tolerated treatment well; only 1 cat had a delay in the treatment schedule because of neutropenia.

Clinical Implications

Use of a multidrug chemotherapeutic protocol that includes l-asparaginase and doxorubicin results in minimal adverse effects and prolonged survival times in cats with alimentary malignant lymphoma. (J Am Vet Med Assoc 1998;213:1144-1149)

Free access
in Journal of the American Veterinary Medical Association

Objective

To determine quality and duration of progression-free survival (PFS) time in dogs with periodontal tumors after definitive megavoltage irradiation and to analyze prognostic factors for PFS time and patterns of treatment failure.

Design

Prospective clinical trial.

Animals

47 dogs with acanthomatous, fibromatous, or ossifying epulis.

Procedure

Dogs were treated with 48 Gy over 4 weeks on an alternate-day schedule of 4 Gy/fraction. Multivariate analysis was done by use of Cox's proportional hazards regression model to determine prognostic factors for PFS time.

Results

The only independent prognostic factor for PFS time was tumor T stage. Pattern of local tumor recurrence (marginal vs infield regrowth) was independent of clinical stage, tumor location, and site. In 4% of the dogs, severe acute radiation reactions in the final week of treatment resulted in treatment discontinuation. In 6.4% of the dogs, chronic radiation reactions included bone necrosis.

Clinical Implications

Irradiation was a safe and effective treatment of small (T1 and T2 stage) periodontal tumors. The usefulness of the radiation protocol in this study is limited in dogs with large (T3) tumors, particularly those located in the caudal half of the oral cavity, because of poor results and high risk of acute radiation toxicoses. (J Am Vet Med Assoc 1997;210:785–788

Free access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine the incidence of bovine papillomavirus (BPV) type 1 or 2 in sarcoids and other samples of cutaneous tissues collected from horses in the western United States.

Animals—55 horses with sarcoids and 12 horses without sarcoids.

Procedure—Tissue samples (tumor and normal skin from horses with sarcoids and normal skin, papillomas, and nonsarcoid cutaneous neoplasms from horses without sarcoids) were collected. Tissue samples were analyzed for BPV-1 or -2 DNA, using a polymerase chain reaction (PCR) and restriction fragment length polymorphism. The PCR products from 7 sarcoid- affected horses were sequenced to evaluate percentage homology with expected sequences for BPV-1 or -2.

Results—Most (94/96, 98%) sarcoids contained BPV DNA. Sixty-two percent of the tumors examined had restriction enzyme patterns consistent with BPV-2. Thirty-one of 49 (63%) samples of normal skin obtained from horses with sarcoids contained BPV DNA. All samples subsequently sequenced had 100% homology with the expected sequences for the specific viral type. All tissues from healthy horses, nonsarcoid neoplasms, and papillomas were negative for BPV DNA.

Conclusions and Clinical Relevance—Bovine papillomaviral DNA was detected in essentially all sarcoids examined. There appears to be regional variation in the prevalence of viral types in these tumors. The fact that we detected viral DNA in normal skin samples from horses with sarcoids suggests the possibility of a latent viral phase. Viral latency may be 1 explanation for the high rate of recurrence following surgical excision of sarcoids. (Am J Vet Res 2001;62:741–744)

Full access
in American Journal of Veterinary Research