Weekly administration of low-dose doxorubicin for treatment of malignant lymphoma in dogs

Nine dogs with intermediate- or high-grade lymphoma were prospectively entered into a protocol to be given a total of 15 weekly doses of doxorubicin (10 mg/m2 of body surface, IV) in an attempt to eliminate all clinical evidence of neoplasia, with minimal risk of drug toxicity. Eight of these dogs did not complete the protocol because of progression of the disease. The median number of doses administered to dogs that developed progressive disease before the regimen was completed was 5 (range, 2 to 9). Seven dogs achieved partial (n = 5) or complete (n = 2) remission, with median duration of 14 days (range, 7 to 231 days). The dog that was given all 15 weekly treatments remained in complete remission for 231 days. Complete remission that lasted for 14 days was observed in another dog. Toxicosis developed in 3 dogs; signs of toxicosis were generally mild and included colitis (n = 1), vomiting (n = 1), neutropenia (n = 1), and lethargy (n = 1). The lowest neutrophil count (1,876 cells/microliter) was seen in one dog after 7 doses of doxorubicin were given. Doxorubicin at dosage of 10 mg/m2/wk appears to be safe, but is generally ineffective for treatment of lymphoma.     

A combination chemotherapy protocol with dose intensification and autologous bone marrow transplant (VELCAP-HDC) for canine lymphoma

Twenty-eight dogs with lymphoma were treated with a 12-week, 5-drug chemotherapy protocol concluding with high-dose cyclophosphamide supported by autologous bone marrow transplants. A dose escalation design was used to determine the maximum tolerated cyclophosphamide dose (MTD) in this setting. Three cyclophosphamide dose levels were given: 300 mg/ m2 IV (groupl, 3 dogs), 400 mg/m2 IV (group 2, 12 dogs), and 500 mg/m2 IV (group 3, 13 dogs); and the MTD was 500 mg/m2 IV. Toxicity was common but mild, and the dose-limiting toxicity was myelosuppression, specifically neutropenia. No dog died as a result of treatment-related toxicity. One dog in group 3 developed fever, neutropenia, and presumed sepsis and responded promptly to routine management. No other dog required hospitalization. Lower stage and higher cyclophosphamide dose (both increasing dose [study groups 1-3], and the highest dose [group 3]) compared with the lower doses combined (groups 1 and 2) were significantly associated with longer remission duration (all P < .0001). Median remission duration for dogs in group 3 was 54 weeks, compared with 21 weeks for dogs in groups 1 and 2 combined. Factors associated with longer survival time were lower stage (P = .042) and higher cyclophosphamide dose (both increasing dose [study groups 1-3], and the highest dose [group 3] compared with the lower doses combined [groups 1 and 2]) (P = .027). Median survival time for dogs in group 3 was 139 weeks, compared with 43 weeks and 68 weeks for dogs in groups 1 and 2, respectively.     

The efficacy and adverse event profile of dexamethasone,melphalan, actinomycin D,and cytosine arabinoside (DMAC) chemotherapy in relapsed canine lymphoma

In this retrospective study, a chemotherapy protocol using dexamethasone, melphalan, actinomycin D, and cytosine arabinoside (DMAC) was evaluated for efficacy and adverse event profile as a first line rescue protocol in 86 client-owned dogs previously treated with a CHOP-based protocol. Forty-three dogs (43%) achieved remission (16% complete remission, 27% partial remission), and 57% were non-responders. The median overall progression-free survival (PFS) was 24 days. Adverse events included thrombocytopenia in 41% of dogs, neutropenia in 17% of dogs, and gastrointestinal toxicity in 13% of dogs. Overall, 16% (13/79) dogs experienced grade III to IV thrombocytopenia, 8% (6/74) dogs grade III to IV neutropenia and 1% (1/79) dogs grade III to IV gastrointestinal toxicity. The efficacy of the DMAC protocol is similar to that of other rescue protocols in dogs with relapsed lymphoma but is associated with shorter PFS. The main toxicity is thrombocytopenia, which may limit treatment.     

Dexamethasone, melphalan, actinomycin D, cytosine arabinoside (DMAC) protocol for dogs with relapsed lymphoma

BACKGROUND: In general, treatment of relapsed lymphoma is associated with a lower probability of response and shorter duration of remission. The purpose of this study was to evaluate the efficacy of the combination chemotherapy protocol DMAC (dexamethasone, melphalan, actinomycin D, and cytosine arabinoside) for reinduction of remission in dogs with relapsed lymphoma. HYPOTHESIS: That DMAC would be an effective reinduction protocol for dogs with relapsed lymphoma. ANIMALS: Fifty-four dogs. RESULTS: Seventy-two percent of the dogs achieved remission (44% complete remission [CR] and 28% partial remission [PR]), 11% had stable disease (SD), and 17% had progressive disease (PD). The median remission duration was 61 days (range, 2-467+ days). The median remission durations for dogs with CR, PR, and SD were 112, 44, and 27 days, respectively. Factors that affected the response rate were previous treatment with doxorubicin and an inability to achieve remission with the previous protocol. Thrombocytopenia occurred in 56% of the dogs (grade 1 in 3 dogs, grade 2 in 6 dogs, grade 3 in 7 dogs, and grade 4 in 7 dogs) and neutropenia in 17% of the dogs (grade 2 in 1 dog, grade 3 in 2 dogs, and grade 4 in 4 dogs). Gastrointestinal toxicosis occurred in 22% of the dogs (grades 1 in 5 dogs, grade 2 in 3 dogs, and grade 3 in 1 dog). CONCLUSIONS AND CLINICAL IMPORTANCE: The DMAC protocol is an effective rescue protocol for dogs with relapsed multicentric lymphoma. Although thrombocytopenia is a common manifestation of toxicity, in general, the protocol is well tolerated.     

Treatment of vascular and soft-tissue sarcomas in dogs using an alternating protocol of ifosfamide and doxorubicin

A retrospective analysis was done to assess the toxicity and efficacy associated with an alternating chemotherapy protocol of ifosfamide (375 mg m^?2) and doxorubicin (30 mg m^?2) for adjuvant treatment of 39 dogs with sarcomas. Twelve dogs had various soft‐tissue sarcomas and 27 dogs had hemangiosarcoma (HSA). Complete blood counts were evaluated 7 days after the first dose of ifosfamide and doxorubicin. One dog had grade 4 neutropenia (<500 µL^?1) after treatment with ifosfamide and one dog had grade 3 neutropenia (500–1000 µL^?1) after treatment with doxorubicin. One dog treated with doxorubicin was hospitalized for 24 h due to vomiting. The median survival time (ST) for the 27 dogs with HSA treated by surgery and with doxorubicin/ifosfamide was 149 days (mean 366 days). Although the protocol of alternating ifosfamide and doxorubicin was well tolerated, it failed to result in a statistically significant improvement in the ST when compared to a historical population of dogs with stage 2 splenic HSA treated by surgery alone.     

Evaluation of ifosfamide for treatment of various canine neoplasms

lfosfamide (3-[2-chloroethyl]-2[(2 chloroethyl)amino]tetrahydro-2H-1,3,2-oxazaphosphorine 2-oxide) is an alkylating agent with a broad spectrum of antitumor activity. The efficacy and toxicity of ifosfamide were evaluated in 72 dogs with spontaneously occurring tumors. Forty dogs (56%) had lymphoma, 31 (43%) had sarcomas, and 1 had a metastatic carcinoma. Five dogs received ifosfamide at dosages <350 mg/m2 IV. Neither toxicity nor response were observed, and the remaining dogs received ifosfamide at 350 mg/m2 (n = 18) and 375 mg/m2 body surface area IV (n = 49). Saline diuresis and the thiol compound mesna were used to prevent urothelial toxicity. Fifty-two dogs had measurable tumors and could be evaluated for response. Complete responses were seen in 1 dog with metastatic leiomyosarcoma of the urinary bladder and in 1 dog with metastatic cutaneous hemangiosarcoma. One dog with lymphoma had a partial response for 112 days. Six dogs with splenic hemangiosarcoma received ifosfamide postsplenectomy and their median survival time was 147 days. The acute dose limiting toxicity was neutropenia 7 days after administration of ifosfamide. The median and mean neutrophil counts 7 days after ifosfamide at 350 mg/m2 were 2,035 cells/microL and 4,773 cells/microL, respectively (n = 12). The median and mean neutrophil counts 7 days after ifosfamide at 375 mg/m2 were 2,500 cells/microL and 3,594 cells/microL, respectively (n = 37). No dog developed clinical or microscopic evidence of hemorrhagic cystitis. Ifosfamide appears safe to use in tumor-bearing dogs, and the evaluation of combination chemotherapy protocols that include ifosfamide should be considered.     

Monthly application of 10 per cent moxidectin and 2{middle dot}5 per cent imidacloprid spot-on to prevent relapses in generalised demodicosis: a pilot study

Canine generalised demodicosis (GD) can be difficult to cure, with some dogs requiring life-long treatment. The aim of this pilot study was to evaluate the effectiveness of monthly 10 per cent moxidectin/2·5 per cent imidacloprid spot-on in maintaining long-term (12 months) clinical and parasitological remission in dogs with relapsing GD. Fourteen dogs were included: 10 with juvenile-onset GD (JOGD) and four with adult-onset GD (AOGD). All?dogs had been treated previously and relapsed (1-4 times). Each dog was treated again with either milbemycin oxime 2 mg/kg or ivermectin 400 μg/kg orally once daily, until two consecutive negative skin scrapings at one-month intervals (total 4-7 months of treatment). After treatment discontinuation, 10 per cent moxidectin/2·5 per cent imidacloprid spot-on was applied monthly for 12 months. Dogs were rechecked after 1, 2, 3, 6 and 12 months, and multiple skin scrapings were taken. Twelve dogs completed the study and were clinically normal and parasitologically negative at each recheck (four dogs with AOGD and eight with JOGD). One dog died suddenly for unrelated reasons, and one dog relapsed. Results of this pilot study suggest that monthly application of 10 per cent moxidectin/2·5 per cent imidacloprid spot-on may be effective as maintenance therapy in relapsing cases of GD.     

Efficacy and toxicity of paclitaxel (Taxol) for the treatment of canine malignant tumors

Paclitaxel (Taxol) was administered to 25 dogs with histologically confirmed malignant tumors at a dosage of 165 mg/m2 i.v. over 3-6 hours every 3 weeks. Dogs received premedication with antihistimines and corticosteroids to reduce hypersensitivity reactions. However, 64% of the dogs still experienced allergic reactions. Six dogs (24%) had grade 3 or 4 neutropenia, 6 dogs (24%) required hospitalization and 3 dogs (12%) died of sepsis. Five dogs (20%) had a partial response (osteosarcoma [2 dogs] mammary carcinoma [2 dogs] and malignant histiocytosis [1 dog]) for a median duration of 53 days. The overall toxicity was unacceptable at the 165 mg/m2 dose. Therefore, subsequent evaluations of paclitaxel in tumor-bearing dogs should a starting dose of 132 mg/m2 i.v. every 3 weeks.     

Phase I Evaluation of Doxorubicin and Whole-body Hyperthermia in Dogs with Lymphoma

Fifteen previously untreated dogs with histologically confirmed, high-grade multicentric lymphoma were entered into a phase I study to evaluate combined doxorubicin and whole-body hyperthermia (DOX/WBH). Groups of three, four, and eight dogs were treated with whole-body hyperthermia and concurrent doxorubicin at 12 mg/m2, 24 mg/m2 and 30 mg/m2, respectively, after one doxorubicin induction dose at 30 mg/m2. Plateau temperature (42 +/- 0.1 degree C) was maintained for 90 minutes using a radiant heating device. A total of five DOX/WBH treatments per dog were planned, and these were given every 21 days. Treatment-related toxicity was not seen in the 12-mg/m2 doxorubicin dose group. Tumor progression prohibited administration of more than three DOX/WBH treatments to any dog in the 12-mg/m2 group. Premature ventricular contractions developed after the fifth treatment in one of the four dogs treated with 24 mg/m2 of doxorubicin. Two dogs (25%) in the 30-mg/m2 dose group had treatment-related toxicity. One dog experienced acute serious myelosuppression 1 week after the third treatment. This dog received all planned DOX/WBH treatments. Asymptomatic cardiac toxicosis consisting of decreased ejection fraction and fractional shortening developed in the second dog. This dog received only two DOX/WBH treatments. The three dogs treated at 12 mg/m2 had partial responses of short duration (60-83 days). Four dogs treated at 24 mg/m2 had complete responses for 150, 164, 186, and 200 days. Eight dogs treated at 30 mg/m2 had complete responses with a mean and median duration of 241 and 190 days, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)     

Prospective trial of metronomic chlorambucil chemotherapy in dogs with naturally occurring cancer

The purpose of this study was to assess the toxicoses and antitumor activity of metronomic chlorambucil at a dosage of 4 mg m(-2) daily in dogs with naturally occurring cancer. Thirty-six dogs were enrolled in the study. The protocol was well tolerated with no grade 3 or 4 toxicoses noted. Complete remission was achieved, and lasted over 35 weeks in three dogs (mast cell tumour, soft tissue sarcoma and thyroid carcinoma). Partial remission was noted in 1 dog with histiocytic sarcoma (39 weeks duration) for an overall remission rate of 11% (4 of 36). Stable disease was noted in 17 dogs (47%) with various other cancers. The median progression-free interval was 61 days, and the median survival time was 153 days. Chlorambucil given in a metronomic protocol showed antitumor activity in dogs with a variety of naturally occurring cancers.     

Use of allopurinol for maintenance of remission in dogs with leishmaniasis

Current treatments for infected dogs with leishmaniasis do not always provide long-term control of the disease and clinical relapses are common. In this study, the usefulness of long-term allopurinol administration in the maintenance of clinical remission in canine leishmaniasis was evaluated. Fifteen dogs with natural leishmania infection were subjected to an initial treatment based on the simultaneous administration of meglumine antimoniate (100 mg/kg/day) and allopurinol (30 mg/kg/day). Once clinical remission was achieved, a maintenance treatment with allopurinol (20 mg/kg/day) administered for one week a month was instituted. Results were compared with those of a retrospective control group comprising 15 infected dogs which only followed the induction treatment. Relapses occurred in 86 per cent of control dogs within 14 months of discontinuing treatment. In contrast, those dogs on intermittent oral allopurinol administration were successfully maintained in clinical remission for a follow-up period of 10 to 44 months. In this latter group, specific antibody titres decreased or were unchanged, no side effects directly attributable to allopurinol were seen and treatment was well accepted by the owners. It is concluded that long-term intermittent administration of allopurinol is an effective way of maintaining clinical remission in dogs with leishmaniasis.     

Treatment of canine mast cell tumors with CCNU (lomustine)

The efficacy and toxicity of CCNU (1-[2-chloroethyl]3-cyclohexyl-1-nitrosourea) were evaluated in 23 dogs with measurable mast cell tumors (MCT). Twenty-two dogs had cutaneous MCT and 1 dog had an intranasal MCT Nineteen (83%) dogs had biopsy of their original mass performed and 4 (17%) had aspiration cytology of masses. Of the 19 tumors histologically graded, 1 (5%) neoplasm was classified as grade I, 10 (53%) were grade II, and the remaining 8 (42%) were grade III. Dogs were treated with CCNU at a dosage of 90 mg/m2 body surface area every 3 weeks. Response could be evaluated in 19 dogs. Eight of the 19 dogs (42%) had a measurable response to CCNU. One dog had a durable complete response for 440 days. Seven dogs (37%) had a partial response for a median and mean duration of 77 days and 109 days, respectively (range, 21-254 days). Treatment with CCNU resulted in stable disease in 6 dogs (32%) for a median and mean duration of 78 days and 122 days, respectively (range, 42-347 days). The acute dose-limiting toxicity was neutropenia 7 days after administration of CCNU. The median and mean neutrophil counts 7 days after CCNU were 1,452 cells/microL and 1,683 cells/microL, respectively (n = 17). Other toxicoses were uncommon. CCNU should be considered an active agent in the treatment of MCT in dogs.     

Results of non-selective adrenocorticolysis by o,p'-DDD in 129 dogs with pituitary-dependent hyperadrenocorticism

One hundred and twenty-nine dogs with pituitary-dependent hyperadrenocorticism were treated according to a protocol aimed at the complete destruction of the adrenal cortices by the administration of o,p'-DDD (mitotane) at a daily dose of 50 to 75 mg/kg bodyweight for 25 days. On the third day, glucocorticoid and mineralocorticoid supplementation was begun for the induced adrenocortical insufficiency. The first followup examination after completion of the 25-day course and the subsequent twice-yearly follow-up examinations included physical examination and measurements of plasma concentrations of sodium and potassium to optimise substitution therapy. In 19 dogs the full course of 25 days treatment could not be completed. Of the 110 dogs which received the full course of treatment, the administration had to be stopped temporarily in 32 because of side-effects, such as anorexia and vomiting. The actual dose of o,p'-DDD administered was not significantly different in the dogs with and without these side-effects. Clinical remission occurred in 111 dogs (86 per cent), of which 43 (39 per cent) had a relapse. The estimated one-year disease-free fraction was 77 per cent (95 per cent confidence interval [CI]: 67 to 85 per cent). The estimated one-year survival fraction was 80 per cent (95 per cent CI: 71 to 87 per cent), the two-year survival was 69 per cent (95 per cent CI: 59 to 78 per cent), and the three-year survival was 61 per cent (95 per cent CI: 49 to 71 per cent). The bodyweight and age of the dog, and vomiting occurring during the period of treatment, were positively correlated with the length of the disease-free period, whereas weakness during the treatment and resistance to dexamethasone suppression of the urinary corticoid/creatinine ratios at the start of the treatment were associated with a relatively short survival time.     

Phase I Dose Escalation of Single‐Agent Vinblastine in Dogs

Background: Vinblastine (VBL) is commonly used in dogs at a dosage of 2.0 mg/m². The minimal toxicity observed at this dosage indicates that higher dosages might be well tolerated. Hypothesis: The maximum tolerated dosage (MTD) for a single VBL treatment is higher than the previously published dosage of 2.0 mg/m². Animals: Twenty‐three dogs with lymphoma or cutaneous mast cell tumors. Methods: Dogs received 1 single‐agent VBL treatment IV. The starting dosage was 3.0 mg/m², and dosages were increased in increments of 0.5 mg/m² in cohorts of 3 dogs. Hematologic toxicity was assessed with weekly CBCs. Gastrointestinal toxicity was assessed from medical histories from owners. Once the MTD was determined, additional dogs were treated with VBL at that dosage. Dogs whose cancers responded to VBL continued to receive treatments q2–3 weeks. Results: VBL dosages ranged from 3.0 to 4.0 mg/m². Neutropenia was the dose‐limiting toxicity, with the nadir identified 7 days after treatment and resolving by 14 days after treatment. The MTD was 3.5 mg/m². Sixteen dogs were treated at this dosage, and 3 experienced severe toxicity characterized by asymptomatic grade 4 neutropenia, febrile grade 4 neutropenia, and death. Gastrointestinal toxicity was mild and self‐limiting. Preliminary evidence of antitumor activity was identified in 2 of 12 dogs with lymphoma treated at the MTD. Conclusions and Clinical Importance: In dogs, single‐agent VBL is well tolerated at a dosage of 3.5 mg/m² IV. At this dosage, the minimum safe treatment interval is q2 weeks, and adjunct treatment with prophylactic antibiotics should be considered.     

Efficacy and Toxicity of Doxorubicin/Cyclophosphamide Maintenance Therapy in Dogs with Multicentric Lymphosarcoma

Doxorubicin/cyclophosphamide were evaluated as maintenance drugs for dogs with multicentric lymphosarcoma (n = 28). Median remission time of all dogs was 173 days. Remission duration was shorter, however, in dogs with stage IV/V disease, in dogs with pretreatment hypoalbuminemia, and in dogs that had received glucocorticoids before initiation of chemotherapy (P less than 0.04). Nineteen dogs were evaluable for toxicity. Dose-limiting gastrointestinal toxicosis was observed in three dogs, neutropenia was observed in three dogs, and cardiomyopathy was observed in three dogs. The doxorubicin/cyclophosphamide protocol described in this report is safe and effective in treating canine multicentric lymphosarcoma. Clinical stage, pretreatment steroid therapy, and hypoalbuminemia are prognostic factors for response to this protocol.     

Prognostic variables in canine multicentric lymphosarcoma

This paper presents the results of a prospective study to investigate the prognostic value of clinical staging, histological grading, immunophenotype, mitotic count and average numbers of argyrophilic nucleolar organiser region counts in dogs with multicentric lymphosarcoma treated with a standard chemotherapy protocol comprising vincristine, cyclophosphamide and prednisolone. Forty-nine dogs were treated according to the study protocol. Univariate and multivariate analysis with regression modelling was used to evaluate the prognostic importance of patient and tumour variables upon tumour response and relapse-free survival. Thirty-seven dogs (76 per cent) achieved a complete remission, seven (14 per cent) a partial remission and five (10 per cent) failed to respond to treatment. None of the variables examined had a statistically significant effect upon tumour response. Tumour immunophenotype was the only parameter found to have a significant influence on patient survival, the hazard ratio for T-cell versus B-cell immunophenotype was 3.99 with 95 per cent confidence interval from 1.399 to 11.372, P = 0.035.     

Cisplatin Therapy in 41 Dogs With Malignant Tumors

Forty-one dogs with a variety of histopathologically diagnosed, measurable tumors were treated with cisplatin (cis-diamminedichloroplatinum, Platinol, Bristol Laboratories, Syracuse, NY 13221-4755) as a single agent at a dosage of 60 mg/m2 given intravenously at 3-week intervals. In an attempt to avoid renal toxicity of cisplatin, saline diuresis was induced and maintained for 4 hours before and 2 hours following cisplatin administration. The dogs received one to ten doses of cisplatin. To determine response to therapy and to monitor toxicity of the drug, the dogs were evaluated with physical examinations including tumor measurements, radiography, complete blood counts, platelet counts, urinalyses, serum urea nitrogen concentrations, and serum creatinine concentrations. An overall response rate of 19% was observed. Complete remission occurred in one of 11 dogs with squamous cell carcinomas and one of one dog with a mediastinal undifferentiated carcinoma. Partial remissions were documented in one of 11 dogs with squamous cell carcinomas, two of three dogs with metastatic osteosarcomas, one of three dogs with nasal adenocarcinomas, and one of one dog with a thyroid adenocarcinoma. Toxic side effects were primarily gastrointestinal in nature, with vomiting occurring 1-6 hours after cisplatin administration in 27 of 41 dogs. Severe anorexia occurred in three dogs, and hemorrhagic diarrhea was observed in one dog. One dog developed grand mal seizures and died 3 hours following therapy. Granulocytopenia was documented in six dogs, and thrombocytopenia was observed in four dogs. One dog showed an increase in serum urea nitrogen and creatinine concentrations, but this patient had known pre-existing renal disease.(ABSTRACT TRUNCATED AT 250 WORDS)     

A phase II clinical trial of vinorelbine in dogs with cutaneous mast cell tumors

Background: Few effective drugs are available to treat dogs with locally aggressive or metastatic mast cell disease.
Hypothesis: Vinorelbine, a semisynthetic derivative of vinblastine, is an effective drug for the treatment of canine mast cell tumors (MCT).
Animals: Twenty-four dogs with cutaneous MCT.
Methods: Dogs with at least 1 measurable, cytologically confirmed, and previously untreated cutaneous MCT received a single treatment with vinorelbine at the previously established dosage of 15 mg/m² IV. Tumor measurements and CBC were evaluated before and 7 days after treatment. Adverse events were graded according to Veterinary Cooperative Oncology Group (VCOG) guidelines.
Statistics: Data were accrued in accordance with a Simon's 2-stage design with a noninteresting response rate of .05, a target response of .25, and α and β values of .10.
Results: Three of 24 dogs (13%) had a response to treatment, including 1 measurable complete response and 1 measurable partial response. The 3rd dog had microscopic complete response to treatment with stable measurable disease. Twenty other dogs (83%) had stable disease and 1 dog (4%) had progressive disease. Neutropenia occurred in 13 dogs (54%) (grade 1, n = 4; grade 3, n = 6; grade 4, n = 3). Gastrointestinal toxicity occurred in 11 dogs (46%) (anorexia: grade 1, n = 3; grade 2, n = 1; grade 3, n = 1; diarrhea: grade 1, n = 2; grade 3, n = 1; vomiting: grade 1, n = 5; grade 3, n = 1).
Conclusions and Clinical Importance: Vinorelbine was associated with an overall response rate of 13% and a high prevalence of neutropenia. Additional studies are indicated to determine if repeated dosing of vinorelbine or combination of vinorelbine with other drugs increases the observed biologic activity against canine MCT.     

Comparison of non-selective adrenocorticolysis with mitotane or trilostane for the treatment of dogs with pituitary-dependent hyperadrenocorticism

Forty-six dogs with pituitary-dependent hyperadrenocorticism were treated with mitotane by the non-selective adrenocorticolysis protocol and 40 were treated twice a day with trilostane. The treatment groups were compared by chi-squared tests, and survival data were analysed using Kaplan-Meier survival plots and a Cox proportional hazard method. The non-selective adrenocorticolysis protocol was very effective (89 per cent), its toxicity was moderate (24 per cent) and there were fewer recurrences (29 per cent) than reported with the classical selective adrenocorticolysis protocol (58 per cent). In a multivariate model, age and bodyweight at diagnosis were significantly negatively correlated with survival time. The median survival time of the dogs treated with trilostane twice a day (900 days) was longer (P=0.05) than that of the dogs treated with mitotane (720 days).     

Unilateral arytenoid lateralisation: An assessment of technique and long term results in 62 dogs with laryngeal paralysis

Sixty-two dogs with laryngeal paralysis were presented over a three year period. Presenting clinical signs included inspiratory stridor (100 per cent), exercise intolerance or syncopal episodes (81 per cent), loss or alteration in phonation (48 per cent) and coughing or gagging when eating (29 per cent). Causes of the paralysis were determined as traumatic (two dogs), neoplastic (two dogs), iatrogenic (two dogs), congenital (one dog) and idiopathic (55 dogs). Unilateral arytenoid lateralisation was performed in all dogs. The perioperative complication rate was approximately 10 per cent, while the success rate as judged by owners one year postoperatively was greater than 90 per cent. The technique avoided many of the recorded complications of intralaryngeal surgery. Operative times were short and the requirement for postoperative monitoring was minimal. Increasing familiarity with the technique favourably influenced the incidence of complications and the success rate.