Histology of ferret skin: preweaning to adulthood.

Ferrets are important companion animals that incur a multitude of cutaneous diseases requiring diagnostic dermatohistopathology. This study provides a description of the histology of normal ferret skin, emphasizing changes in the interval from preweaning to adulthood, an essential basis for identification of pathological situations. Skin samples obtained post-mortem from 29 topographical sites on 41 ferrets, revealed in the haired, general body surface skin an epidermis consisting of strata basale, spinosum, granulosum, and corneum and a dermis consisting of strata papillare and reticulare. Adult skin contained compound hair follicles composed of one primary hair and a collection of secondary hairs with a primary to secondary ratio of 1/5-1/15. All hairs emerged through the same follicle outlet of the skin surface. There was associated with each primary follicle, an arrector pili muscle, a multilobular sebaceous gland, and a coiled tubular sweat gland, but secondary hairs lacked these features. Compound follicles, grouped mainly as triads across the body surface, were already fully formed in the youngest group studied (3 to 6 weeks). The secondary hairs all developed from one specific region of the primary follicles and smaller ones were formed with increasing age. The differences found in specialized body regions are described. Demodex sp. mites were found in follicles and sebaceous glands in nine of 25 individuals in the perianal, vulvar, preputial, facial, and caudal abdominal skin.

Pretreatment tumor prostaglandin E2 concentration and cyclooxygenase-2 expression are not associated with the response of canine naturally occurring invasive urinary bladder cancer to cyclooxygenase inhibitor therapy.

The purpose of this study was to determine the extent to which pretreatment prostaglandin E2 (PGE2) concentration and cyclooxygenase-2 (cox-2) expression could be used to predict the antitumor activity of cox inhibitor treatment in naturally occurring canine transitional cell carcinoma of the urinary bladder (TCC). Snap frozen tissues (to measure PGE2) and formalin-fixed TCC samples (for cox-2 immunohistochemistry) were obtained by cystoscopy or surgery. Complete tumor staging was performed before and after one month of treatment with the cox inhibitor, piroxicam (0.3 mg/kg q24 h po). The pretreatment PGE2 concentration ranged from 57 to 1624 ng/g of TCC tissue; n=18 dogs). Cox-2 immunoreactivity was observed in all TCC samples. There was no association between PGE2 concentration, cox-2 expression, and change in tumor volume with piroxicam treatment. In conclusion, cox-2 expression or PGE2 concentration alone, or the combination of the two was not useful in predicting response to piroxicam treatment in canine TCC.

Carboplatin and piroxicam therapy in 31 dogs with transitional cell carcinoma of the urinary bladder.

Invasive transitional cell carcinoma (TCC) of the urinary bladder responds poorly to medical therapy. Combining platinum chemotherapy with a cyclooxygenase (cox) inhibitor has shown promise against canine TCC, where the disease closely mimics the human condition. A phase II clinical trial of carboplatin combined with the cox inhibitor, piroxicam, was performed in 31 dogs with naturally occurring, histopathologically confirmed, measurable TCC. Complete tumour staging was performed before and at 6-week intervals during therapy. Tumour responses in 29 dogs included 11 partial remissions, 13 stable disease and five progressive disease. Two of the 31 dogs were withdrawn prior to the re-staging of the tumour. Gastrointestinal toxicity was observed in 23 dogs. Hematologic toxicity was noted in 11 dogs. The median survival was 161 days from first carboplatin treatment to death. In conclusion, carboplatin/piroxicam induced remission in 40% of dogs providing evidence that a cox inhibitor enhances the antitumour activity of carboplatin. The frequent toxicity and limited survival, however, do not support the use of this specific protocol against TCC.

Evaluation of piroxicam for the treatment of oral squamous cell carcinoma in dogs.

OBJECTIVE: To evaluate the use of piroxicam for the treatment of oral squamous cell carcinoma in dogs. DESIGN: Prospective case series. ANIMALS: 17 dogs with measurable oral squamous cell carcinoma. PROCEDURE: Dogs were treated with piroxicam at a dosage of 0.3 mg/kg (0.14 mg/lb) of body weight, PO, every 24 hours until progressive disease or unacceptable signs of toxicosis developed or the dog died. RESULTS: One dog had a complete remission (maxillary tumor), and 2 dogs had partial remissions (lingual tumor and tonsillar tumor). An additional 5 dogs had stable disease, including 1 with a maxillary tumor, 2 with mandibular tumors, and 2 with tonsillar tumors. Variables associated with tumor response were not identified. Median and mean times to failure for the 3 dogs that had a remission were 180 and 223 days, respectively. Median and mean times to failure for the 5 dogs with stable disease were 102 and 223 days, respectively. Time to failure was positively associated with tumor response and negatively associated with tumor size. One dog had mild adverse gastrointestinal tract effects that resolved with the addition of misoprostol to the treatment regimen. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that piroxicam may be useful in the treatment of dogs with oral squamous cell carcinoma; response rate was similar to that reported for other cytotoxic treatments. Larger-scale studies are warranted to determine what role piroxicam may have, alone or in combination with other treatments, for the treatment of dogs with oral squamous cell carcinoma.

Evaluation of dual energy x-ray absorptiometry for in situ measurement of bone mineral density of equine metacarpi.

OBJECTIVE: To determine the accuracy and precision of dual energy x-ray absorptiometry (DEXA) for measuring bone mineral density in horses in situ. Sample Population-12 randomly selected forelimbs from 12 horses. PROCEDURE: Metacarpi were scanned in 2 planes and DEXA measurements obtained for 6 regions of interest (ROI). Each ROI was isolated and bone density measured by Archimedes' principle. Linear regression analysis was used to determine the correlation between the 2 measurements at each ROI. An additional metacarpus was measured 10 times to determine the coefficient of variation for both techniques. RESULTS: Dual energy x-ray absorptiometry and bone density were significantly associated at multiple ROI. The addition of age, weight, and soft tissue or bone thickness improved these associations. Repeated measurements had a low coefficient of variation. CONCLUSIONS AND CLINICAL RELEVANCE: Dual energy x-ray absorptiometry can be used to accurately and precisely measure the bone density in the equine metacarpus. Dual energy x-ray absorptiometry appears suitable for serial in vivo measurement of bone density of the equine metacarpus. Dual energy x-ray absorptiometry may be used for studies to evaluate the effects of diet or drugs on bone density or density changes from bone remodeling that develop prior to stress fractures.

Prostaglandin E2 concentrations in naturally occurring canine cancer.

The purpose of this study was to determine the PGE2 concentration in naturally-occurring cancer in pet dogs and in canine cancer cell lines in order to identify specific types of canine cancer with high PGE2 production which could serve as preclinical models to evaluate anticancer strategies targeting PGE2. PGE2 concentrations were measured by enzyme immunoassay in canine melanoma, soft tissue sarcoma, transitional cell carcinoma, osteosarcoma, and prostatic carcinoma cell lines; in 80 canine tumor tissue samples including oral melanoma (MEL), oral squamous cell carcinoma (SCC), transitional cell carcinoma of the urinary bladder (TCC), lymphoma (LSA), mammary carcinoma (MCA), osteosarcoma (OSA), prostatic carcinoma (PCA); and in corresponding normal organ tissues. High concentrations of PGE(2)(range 400-3300 pg/10(4)cells) were present in cell culture medium from the transitional cell carcinoma, prostatic carcinoma, and osteosarcoma cell lines. PGE2 concentrations in tumor tissues were elevated (tumor PGE2 concentration>mean+2X sd PGE(2)concentration of normal organ tissue) in 21/22 TCC, 5/6 PCA, 7/10 SCC, 5/10 MEL, 3/8 MCA, 4/15 OSA, and 0/9 LSA. Results of this study will help guide future investigations of anticancer therapies that target cyclooxygenase and PGE2.

Cisplatin versus cisplatin combined with piroxicam in a canine model of human invasive urinary bladder cancer.

PURPOSE: More than 12,000 people are expected to die from invasive transitional cell carcinoma (TCC) of the urinary bladder each year in the United States, indicating that more effective therapy is needed. Drugs inhibiting cyclooxygenase (cox) have recently been found to have chemopreventive and antitumor activity and may potentiate the effects of chemotherapy. The purpose of this study was to determine whether cisplatin combined with the cox-inhibitor piroxicam would induce remission more frequently than cisplatin alone in a relevant animal model of human invasive TCC. METHODS: Pet dogs with naturally occurring, histopathologically confirmed, measurable TCC of the urinary bladder were randomized to receive cisplatin (60 mg/m2 i.v. every 21 days) or cisplatin (same dosage) combined with piroxicam (0.3 mg/kg orally every 24 h). Complete staging was performed prior to and at 6-week intervals during therapy. RESULTS: After eight dogs had been evaluated in each treatment group, a significant difference in remission rate was noted (Fisher's Exact test, P < 0.004). Tumor responses in the cisplatin/piroxicam group included two complete remissions (CR), four partial remissions (PR), two stable disease (SD), and no progressive disease (PD). Tumor responses to cisplatin alone in eight dogs were no CR, no PR, four SD, and four PD. Six additional dogs were treated with cisplatin/piroxicam, and in total 10 of 14 dogs had remission (two CR, eight PR). Renal toxicity of cisplatin/ piroxicam was frequent and dose limiting. CONCLUSIONS: Cisplatin/piroxicam induced remission more frequently than cisplatin alone in a canine model of human invasive TCC. Strategies to reduce renal toxicity need to be developed prior to evaluation of cisplatin/piroxicam in humans or general use of this treatment in pet dogs.

Incidence of and breed-related risk factors for gastric dilatation-volvulus in dogs.

OBJECTIVE: To compare incidence of and breed-related risk factors for gastric dilatation-volvulus (GDV) among 11 dog breeds (Akita, Bloodhound, Collie, Great Dane, Irish Setter, Irish Wolfhound, Newfoundland, Rottweiler, Saint Bernard, Standard Poodle, and Weimaraner). DESIGN: Prospective cohort study. ANIMALS: 1,914 dogs. PROCEDURE: Owners of dogs that did not have a history of GDV were recruited at dog shows, and the dog's length and height and depth and width of the thorax and abdomen were measured. Information concerning the dogs' medical history, genetic background, personality, and diet was obtained from owners, and owners were contacted by mail and telephone at approximately 1-year intervals to determine whether dogs had developed GDV or died. Incidence of GDV based on the number of dog-years at risk was calculated for each breed, and breed-related risk factors were identified. RESULTS AND CLINICAL RELEVANCE: Incidence of GDV for the 7 large (23 to 45 kg [50 to 99 lb]) and 4 giant (> 45 kg [> 99 lb]) breeds was 23 and 26 cases/1,000 dog-years at risk, respectively. Of the 105 dogs that developed GDV, 30 (28.6%) died. Incidence of GDV increased with increasing age. Cumulative incidence of GDV was 5.7% for all breeds. The only breed-specific characteristic significantly associated with a decreased incidence of GDV was an owner-perceived personality trait of happiness.

Non-dietary risk factors for gastric dilatation-volvulus in large and giant breed dogs.

OBJECTIVE: To identify non-dietary risk factors for gastric dilatation-volvulus (GDV) in large breed and giant breed dogs. DESIGN: Prospective cohort study. ANIMALS: 1,637 dogs > or = 6 months old of the following breeds: Akita, Bloodhound, Collie, Great Dane, Irish Setter, Irish Wolfhound, Newfoundland, Rottweiler, Saint Bernard, Standard Poodle, and Weimaraner. PROCEDURE: Owners of dogs that did not have a history of GDV were recruited at dog shows, and the dog's length and height and the depth and width of its thorax and abdomen were measured. Information concerning the dog's medical history, genetic background, personality, and diet was obtained from the owners, and owners were contacted by mail and telephone at approximately 1-year intervals to determine whether dogs had developed GDV or died. Incidence of GDV, calculated on the basis of dog-years at risk for dogs that were or were not exposed to potential risk factors, was used to calculate the relative risk of GDV. RESULTS AND CLINICAL RELEVANCE: Cumulative incidence of GDV during the study was 6% for large breed and giant breed dogs. Factors significantly associated with an increased risk of GDV were increasing age, having a first-degree relative with a history of GDV, having a faster speed of eating, and having a raised feeding bowl. Approximately 20 and 52% of cases of GDV among the large breed and giant breed dogs, respectively, were attributed to having a raised feed bowl.

Naturally-occurring canine transitional cell carcinoma of the urinary bladder A relevant model of human invasive bladder cancer.

Invasive bladder cancer results in over 10,000 deaths yearly in the United States alone. More effective therapy for invasive bladder cancer is clearly needed. As new cellular and molecular targets for therapy are identified, relevant animal models are needed to test new therapeutic strategies aimed at these targets prior to human clinical trials. The purpose of this review is to characterize spontaneous invasive transitional cell carcinoma of the urinary bladder (TCC) in dogs, to summarize the similarities and differences between canine and human invasive TCC, and to describe how canine TCC could serve as a relevant model of human invasive bladder cancer. Information was summarized from 102 dogs with TCC evaluated and treated at the Purdue University Veterinary Teaching Hospital, from a review of the Veterinary Medical Data Base, and from reports in the literature. Canine TCC was found to be very similar to human invasive bladder cancer in histopathologic characteristics, molecular features, biological behavior including metastasis, response to medical therapy, and prognosis. Differences between canine and human TCC were few, but included gender predilection with a male:female ratio of 2.8:1 in humans versus a male:female ratio of 0.5:1 in dogs. The location of the TCC within the bladder also differed: Most canine TCC was trigonal in location, whereas more than 50% of human TCC was in the lateral and posterior walls of the bladder. Considering the great similarity between invasive bladder cancer in humans and dogs, spontaneous canine TCC can be considered a relevant animal model of human invasive bladder cancer.

Prevalence of gastric ulcers in show horses.

OBJECTIVE: To determine prevalence and risk factors for gastric ulcers in show horses. DESIGN: Field survey. ANIMALS: 50 horses in active training that had been transported to at least 1 event in the 30 days prior to endoscopy. PROCEDURE: Interview of owner, physical examination, serum biochemical analysis, CBC, and gastric endoscopy were performed. RESULTS: Gastric ulceration was detected in 58% of the horses. Horses with a nervous disposition were more likely to have ulceration than quiet or behaviorally normal horses. Horses with gastric ulceration had significantly lower RBC counts and hemoglobin concentrations than those without ulceration. CONCLUSIONS AND CLINICAL RELEVANCE: Show horses have a high prevalence of gastric ulceration. Lower RBC counts and hemoglobin concentrations may be the result of chronic gastric ulceration.

Functional outcome in dogs after surgical treatment of caudal lumbar intervertebral disk herniation.

Caudal lumbar disk herniations (i.e., third lumbar [L3] to seventh lumbar [L7] intervertebral spaces) represent approximately 15% of surgically treated thoracolumbar disk herniations in dogs. A retrospective case-control study was conducted to determine the postoperative outcome of this subset of dogs in the authors' neurosurgical practice. Medical records (1985 through 1996) were reviewed for dogs with caudal lumbar disk herniation confirmed at surgery. Thirty-six cases were identified. For each case, two dogs that underwent surgical treatment for upper motor neuron thoracolumbar disk herniation (tenth thoracic [T10] to L3 intervertebral spaces) were selected as controls. Probabilities of functional recovery for cases and controls were 81% and 85%, respectively (p value of 0.49). In dogs with caudal lumbar disk herniation, complete sensorimotor loss was the only significant predictor of functional recovery (p value of 0.005). Disk herniations that occur at the thoracolumbar junction and those that occur in the caudal lumbar region should not be considered to be different in terms of surgical treatment and postoperative outcome. The lower motor neuron signs that often accompany caudal lumbar disk herniation reflect the site of spinal cord injury and do not necessarily predict a poor prognosis.

Nematode intestinal parasites of children in rural Guinea, Africa: prevalence and relationship to geophagia.

BACKGROUND: Intestinal parasitism is common among children in developing countries, but the risk factors for infection are not well characterized. METHODS: A stool examination was performed on 286 randomly selected children aged 1-18 years from three rural villages in Guinea, Africa. Information collected by questionnaire was used to examine the relationship between geophagia and infection with intestinal nematodes acquired by ingestion versus skin penetration. RESULTS: Fifty-three per cent of children were infected by at least one type of soil-transmitted nematode. Geophagia was reported by parents to occur in 57%, 53%, and 43%, of children ages 1-5, 6-10, and 11-18 years, respectively. The pattern of geophagia by age and gender of the children more closely resembled the infection pattern for the two orally acquired and soil-transmitted nematodes (Ascaris lumbricoides, Trichuris trichiura) than it did the infection pattern for the two soil-transmitted nematodes that infect by skin penetration (hookworm, Strongyloides stercoralis). CONCLUSIONS: These findings demonstrate that geophagia is an important risk factor for orally acquired nematode infections in African children. Education regarding geophagia prevention should be an integral component of any soil-transmitted parasite control programme.

PIP: Intestinal parasites are routinely found among children in developing countries, but the risk factors of such infection are poorly characterized. The stools of 286 randomly selected children aged 1-18 years from 3 rural villages in Guinea were examined. Data collected via questionnaire were then analyzed to assess the relationship between geophagia, the regular ingestion of soil, and infection with intestinal nematodes acquired through ingestion rather than through skin penetration. 53% of children were infected with at least 1 type of soil-transmitted nematode, and geophagia was reported by parents to occur in 57%, 53%, and 43% of children aged 1-5, 6-10, and 11-18 years, respectively. The pattern of geophagia by age and gender of the children more closely resembled the infection pattern for the 2 orally acquired and soil-transmitted nematodes Ascaris lumbricoides and Trichuris trichiura than it did the infection pattern for the 2 soil-transmitted nematodes which infect by penetrating the skin, hookworm and Strongyloides stercoralis. Geophagia is therefore an important risk factor for orally acquired nematode infections among African children, and education on geophagia prevention should be an integral component of all soil-transmitted parasite control programs.

Complete fractures of the third metacarpal or metatarsal bone in horses: 25 cases (1980-1996).

OBJECTIVES: To compare treatments of complete fractures of the third metacarpal (MC) or metatarsal (MT) bone in horses and to identify factors that could impact prognosis. DESIGN: Retrospective case series. ANIMALS: 25 horses with fractures of the third MC or MT bone that were treated by use of internal fixation, external coaptation, or both. PROCEDURE: Medical records from the Veterinary Medical Data Base of horses treated for fractures of third MC or MT bone at Texas A&M University from 1980 to 1994 and Purdue University from 1980 to 1996 were reviewed. Information on signalment, results of physical and radiographic examinations, treatment, and outcome were obtained. For horses that had radiographic evidence of healing, long-term follow-up information was obtained by telephone contact with owners or referring veterinarians. RESULTS: Age, sex, weight, and limb affected were not related to outcome; however, affected horses were younger than the general hospital populations. Seventeen horses had open fractures at referral. Infection was the most common complication after surgery, with open fractures more likely to become infected. Nonunion in an infected fracture was the most common reason for postoperative failure (7 horses). Long-term follow-up was available for 16 horses; 11 of these had no complications related to surgical repair. CLINICAL IMPLICATIONS: Fractures of the MC or MT bone are not always associated with a poor prognosis in horses. Proper case selection, rigid fracture stabilization, and efforts to prevent or treat infection will improve success rate.

A prospective study of survival and recurrence following the acute gastric dilatation-volvulus syndrome in 136 dogs.

Dogs (n = 136) with gastric dilatation-volvulus (GDV) syndrome were followed over time to measure recurrence and mortality rates and to identify prognostic factors. Thirty-three (24.3%) died or were euthanized during the first seven days. Of 85 cases that were followed for up to three years, nine (10.6%) cases each had a recurrence of GDV and seven (8.2%) cases died or were euthanized. The median survival times for cases that had gastropexies and those that did not were 547 and 188 days, respectively. Depressed or comatose cases on admission were three and 36 times, respectively, more likely to die than alert cases, while cases with gastric necrosis were 11 times more likely to die.

Influence of thoracic conformation and genetics on the risk of gastric dilatation-volvulus in Irish setters.

Body measurements, history of gastric dilatation-volvulus (GDV), and other data were obtained for 155 Irish setters at the 1994 National Specialty Show. The dogs ranged in age from 6.5 months to 12.4 years (mean+/-standard deviation [SD], 3.6+/-2.6 years); 11 (7%) of the dogs had histories of GDV. Gastric dilatation-volvulus risk increased 33% for each year of age (p of 0.01). Dogs with the deepest thorax relative to width (ratio range, 1.61 to 1.85) had a significantly greater GDV risk than those with the shallowest thorax (ratio range, 1.20 to 1.50); the odds ratio was 8.45; the 95% confidence limits were 1.44 to 49.57; and the p value equaled 0.02. Having a relative (particularly a parent) with GDV also increased GDV risk. Five-generation pedigrees yielded a significantly higher mean coefficient of relationship for the 11 dogs with GDV than for the 11 dogs without GDV.

Predisposition to gastric dilatation-volvulus in relation to genetics of thoracic conformation in Irish setters.

Thoracic depth/width ratios (TDWRs) were calculated from measurements of the parents (i.e., common dam and two sires) and puppies in two litters of Irish setters. The TDWRs of the parents, distribution of TDWRs in the litters, and comparisons with earlier population studies suggest that an incompletely dominant major gene and a background of minor genes and environmental factors are responsible for the TDWR. A history of gastric dilatation-volvulus (GDV) (i.e., bloat) was correlated with high TDWRs in this family as it was for Irish setters and certain other breeds studied earlier. It may be possible to reduce the incidence of GDV by selective breeding of dogs with lower TDWRs.

Multiple risk factors for the gastric dilatation-volvulus syndrome in dogs: a practitioner/owner case-control study.

A study was conducted of 101 dogs (i.e., case dogs) that had acute episodes of gastric dilatation-volvulus (GDV) and 101 dogs (i.e., control dogs) with nonGDV-related problems. The control dogs were matched individually to case dogs by breed or size, and age. Predisposing factors that significantly (p less than 0.10) increased a dog's risk of GDV were male gender, being underweight, eating one meal daily, eating rapidly, and a fearful temperament. Predisposing factors that decreased the risk of GDV significantly were a "happy" temperament and inclusion of table foods in a usual diet consisting primarily of dry dog food. The only factor that appeared to precipitate an acute episode of GDV was stress.

Phase II clinical trial of carboplatin in canine transitional cell carcinoma of the urinary bladder.

Fourteen dogs with histologically-confirmed transitional cell carcinoma (TCC) of the urinary bladder were treated with 300 mg/m2 carboplatin every 3 weeks. Response to therapy was assessed with abdominal radiography, double contrast cystography, urinary bladder ultrasonography and thoracic radiography before therapy and at 6-week intervals during therapy. Dogs were monitored for hematologic toxicity with a CBC and platelet count performed immediately before and 10 to 14 days after carboplatin treatment. Tumor responses included progressive disease in 11 dogs and stable disease in 1 dog. Two dogs were euthanized due to carboplatin toxicity before assessment of tumor response. Toxicity included thrombocytopenia with or without neutropenia in 7 dogs and gastrointestinal toxicity in 6 dogs. Carboplatin therapy was not beneficial in the treatment of TCC in the 14 dogs in this study.

Cisplatin treatment of transitional cell carcinoma of the urinary bladder in dogs: 18 cases (1983-1993).

OBJECTIVE: To determine whether cisplatin administered at a dosage of 60 mg/m2 of body surface area, IV, every 21 days, would induce remission of transitional cell carcinoma of the urinary bladder in dogs. DESIGN: Retrospective analysis of medical records. ANIMALS: 18 dogs with histologically confirmed transitional cell carcinoma of the urinary bladder. PROCEDURE: Clinical staging was performed by means of physical examination, contrast cystography or ultrasonography, and thoracic radiography prior to and 42 days after the initiation of cisplatin treatment. Dogs with clinical signs of tumor progression were reevaluated earlier than 42 days in some instances. Complete remission (CR) was defined as complete resolution of measurable tumor. Partial remission (PR) was defined as a > or = 50% reduction in tumor volume without development of new tumors. Stable disease was defined as < 50% change in tumor volume at 42 days without development of new lesions. Progressive disease (PD) was defined as > or = 50% increase in tumor volume or development of new tumors at any time. Dogs were reevaluated at 42-day intervals until they had a CR, developed PD, or developed unacceptable adverse effects. RESULTS: Three dogs had a PR, 4 had stable disease, and 9 had PD. Tumor response could not be assessed in 2 dogs: 1 dog developed grand mal seizures 3 hours after the first dose of cisplatin was given and was euthanatized; the other dog continued to have clinical signs of urinary tract obstruction and was euthanatized 8 days after the first dose of cisplatin. Four dogs developed renal azotemia that was suspected to be secondary to cisplatin nephrotoxicity. CLINICAL IMPLICATIONS: The cisplatin dosage was higher than that reported in studies of dogs with transitional cell carcinoma of the bladder. Even with this higher dosage, none of the dogs had a CR, and only 3 of 18 had a PR. A more effective, less toxic treatment for transitional cell carcinoma in dogs is needed.