Combination toceranib and lomustine shows frequent high grade toxicities when used for treatment of non-resectable or recurrent mast cell tumours in dogs: A European multicentre study.

Mast cell tumours (MCTs) in dogs can present in a variety of forms. Non-resectable, recurrent or metastatic MCTs usually carry a poor prognosis and present a therapeutic challenge. Both toceranib and lomustine have shown single agent activity against MCTs in dogs. In this study, 10 dogs with advanced MCTs were enrolled prospectively and treated with toceranib (median dose 2.7mg/kg orally every other day), lomustine (median dose 60mg/m2 orally every 3 weeks) and prednisolone (1mg/kg orally every other day, alternating with toceranib). Severe adverse events (SAEs), requiring alterations in the protocol, occurred in all dogs. The objective response rate was 50%. Three dogs died or were euthanased due to SAEs and therefore enrolment of new dogs was discontinued prematurely. A long term response (>1year) was observed in two dogs. Modifications of the protocol are required for future prospective studies.

Melting curve analysis in canine lymphoma by calculating maximum fluorescence decrease.

PARR is widely used in the diagnostics of canine lymphoma. In human and veterinary medicine, melting curve analysis (MCA) has successfully been introduced to facilitate the process. Since visual interpretation of melting curves can be rather subjective, the purpose of this study was to develop an objective interpretation of melting curves by calculating the maximum fluorescence decrease (dFmax ) within a defined rise of temperature. Lymph node aspirates and blood of 34 dogs with lymphoma and 28 control dogs were tested. 27/34 lymphoma cases were correctly detected to be monoclonal (sensitivity 79%). 2/28 control dogs showed a monoclonal rearrangement (specificity 93%). B- and T-cell neoplasia were still detectable using DNA amount as low as 10 ng. In serial dilutions of tumor DNA with DNA of normal tonsils, the detection limit was 25% for B-cell lymphomas and 100% for T-cell lymphoma, suggesting that PCR conditions could still be optimized.

The tyrosine kinase inhibitor toceranib in feline injection site sarcoma: efficacy and side effects.

Because of their locally invasive growth and high recurrence rate despite of aggressive local therapy, treatment of feline sarcomas is challenging. The tyrosine kinase inhibitor (TKI) toceranib is currently licensed for the treatment of canine mast cell tumours. There are only few reports about TKI usage in cats. Previous studies indicated promising potential of TKI for the treatment of feline injection site sarcoma (FISS). In this prospective clinical trial, 18 cats with unresectable FISS were treated at a target dosage of 3.25 mg kg-1 every other day to evaluate the clinical efficacy and toxicity of toceranib. There was no clinical response measurable. Adverse events were generally mild and temporary. Grade 3 or 4 adverse events developed infrequently and all resolved with drug holidays and dose reductions.

Detection of monoclonality in intestinal lymphoma with polymerase chain reaction for antigen receptor gene rearrangement analysis to differentiate from enteritis in dogs.

The diagnosis of canine intestinal lymphoma by morphological examination is challenging, especially when endoscopic tissue specimens are used. The utility of detection of antigen receptor gene rearrangement by polymerase chain reaction (PARR) in canine lymphoma has been well established, but its usefulness to distinguish enteritis and intestinal lymphoma remains unclear. In this retrospective study we assessed clonality of 29 primary canine intestinal lymphoma, 14 enteritis and 15 healthy control cases by PARR analysis, using formalin-fixed, paraffin-embedded full-thickness tissue specimens. We could detect monoclonal rearrangements in 22 of 29 canine intestinal lymphomas [76%; 95% confidence interval (CI) 56-90%] and polyclonal rearrangements in all of the enteritis and healthy control cases (100%; CI 88-100%). We revealed a predominance of T-cell phenotype compared to B-cell phenotype (85%; CI 65-96% and 15%; CI 4-35%, respectively). We showed that PARR analysis contributes to differentiation of canine intestinal lymphoma from enteritis and to phenotyping of lymphomas.

Masitinib monotherapy in canine epitheliotropic lymphoma.

This study evaluated efficacy and side effects of masitinib in canine epitheliotropic lymphoma. Complete remission occurred in 2 of 10 dogs and lasted for median 85 days. Five dogs went into partial remission for median 60.5 days. Three pretreated dogs did not respond to therapy. Side effects occurred in six dogs and were mostly mild to moderate. Immunohistochemistry was available for eight dogs. KIT receptor was negative in all of them, six of eight lymphomas stained strongly positive for stem cell factor (SCF). platelet-derived growth factor (PDGF)-AA was weakly positive in two and negative in six. PDGF-BB was negative in four tumours, weakly positive in one and strongly positive in three. One was strongly positive for PDGF receptor (PDGFR)-ß, seven were negative for that receptor. Five showed strong expression of PDGFR-α, two showed weak expression, one was negative. In conclusion, masitinib is effective in treating canine epitheliotropic lymphoma. But its effects are most likely not generated through the KIT receptor.

[Quality of life in primary and adjuvant veterinary radiation therapy. An owner survey]. / Lebensqualität der Patienten nach primärer und adjuvanter Strahlentherapie in der Kleintieronkologie. Eine Besitzerumfrage.

OBJECTIVE: External radiation therapy has been available since 2011 for small animals at the University of Munich. The aim of the study was to evaluate the quality of life of treated pets and the satisfaction of their owners. MATERIAL AND METHODS: The questionnaire was sent to the owners of all the pets (n = 91) that had undergone primary or adjuvant radiotherapy at the Clinic of Small Animal Medicine, University of Munich, since April 2011. RESULTS: The questionnaire was returned by 68 (74.7%) owners. According to their assessment, the quality of life improved in 41 cases (60.3%) after treatment where- as in 13 patients (19.1%) a decline was described. The majority of owners (88.2%) would have decided for repeated radiation therapy. CONCLUSION: Improvement of the animals' quality of life is related to a high satisfaction (83.8%) of the owners (p = 0.003) and their positive attitude towards radiotherapy (p = 0.027). CLINICAL RELEVANCE: Analyses showed that for these owners, the treatment was a worthwhile therapy despite it requiring much time and money.

Mesna and furosemide for prevention of cyclophosphamide-induced sterile haemorrhagic cystitis in dogs--a retrospective study.

Sterile haemorrhagic cystitis (SHC) is a possible side effect of cyclophosphamide which can severely impact quality of life. Mesna and diuresis are effective in human medicine to prevent SHC. The aim of the present study was to compare the efficacy of mesna versus diuresis with furosemide in preventing SHC in dogs treated with cyclophosphamide within a multidrug chemotherapy induction protocol for malignant lymphoma. Medical records of dogs treated at the Clinic of Small Animal Medicine, Munich, between 1997 and 2009 were analysed retrospectively. Of the 131 dogs included, 33 received no prophylaxis (group 1), 43 received mesna (group 2), and 55 received furosemide (group 3). Age, gender, breed, bodyweight, body surface area, dose and application method of cyclophosphamide, and the method of SHC prophylaxis were compared between dogs with and without SHC. Six dogs (4.6 per cent) developed SHC. The incidence of SHC in groups 1, 2 and 3 was 4/33 (12.1 per cent), 1/43 (2.3 per cent), and 1/55 (1.8 per cent), respectively. Dogs receiving either mesna or furosemide were significantly less likely to develop SHC (P=0.03). Otherwise no significant differences were found. In conclusion, this study demonstrates the efficacy and the medical indication of mesna and furosemide for prevention of cyclophosphamide-induced SHC.

Lack of association between p53 SNP and FISS in a cat population from Germany.

One recent study indicates a significant association between certain single nucleotide polymorphisms (SNPs) in the genomic sequence of feline p53 and feline injection-site sarcoma (FISS). The aim of this study was to investigate the correlation between a specific nucleotide insertion in p53 gene and FISS in a German cat population. Blood samples from 150 German cats were allocated to a control group consisting of 100 healthy cats and a FISS-group consisting of 50 cats with FISS. All blood samples were examined for the presence of the SNP in the p53 gene. Results found the T-insertion at SNP 3 in 20.0% of the cats in the FISS-group and 19.2% of cats in the control-group. No statistically significant difference was observed in allelic distribution between the two groups. Further investigations are necessary to determine the association of SNPs in the feline p53 gene and the occurrence of FISS.

[Reference values for haematological and clinical-chemical parameters in the dog]. / Hämatologische und klinisch-chemische Referenzwerte für Hunde.

OBJECTIVE: The aim of the study was to establish reference values for haematological and clinical-chemical parameters in adult dogs and to evaluate whether they are influenced by age, sex and feeding. MATERIAL AND METHODS: The study population consisted of 508 clinically healthy dogs of both genders and different breeds aged between ≤ 1 and 17 years. To establish reference values, results of 396 dogs aged 1-9 years were used. Analysis of haematological and clinical-chemical parameters was performed using the following devices: Cell-Dyn 3500, Hitachi 911, GEM Premier 3000 and the coagulometer BE CL 4. The statistical program SPSS was used to calculate the reference values. RESULTS: In 75% of the tested parameters no major discrepancies were noted in comparison to existing reference values. For eosinophils, basophils, monocytes, alanine aminotransferase, alkaline phosphatase, glutamate dehydrogenase, lipase, creatine kinase, bilirubin and creatinine cleardeviationsfromthe existing referencevalues were demonstrated. The reference ranges for eosinophils, monocytes and glutamate dehydrogenase were higher than reported inthe literature whereas for basophils they were lower. The reference ranges for the enzymes alanine aminotransferase, alkaline phosphatase, and lipase in young (< 1 year) and old dogs (≥ 10 years) differed significantly from the reference values of dogs aged 1-9 years. CONCLUSION AND CLINICAL RELEVANCE: Reference require regular re-evaluation because through continuing developments and new knowledge, some factors related to their determination, particularly methods and equipment, change.

European consensus document on mast cell tumours in dogs and cats.

In preparing this document the Authors aimed to pool current information on canine and feline mast cell disease. The information was gathered from international studies and a emphasis was placed on material and opinion with a strong evidence base. We intend it to form the basis of our understanding in this disease at the current time and we anticipate that it will be particularly useful for the general practitioner. It should be emphasized that the authors are presenting this work from a European perspective.

Changes in prevalence of progressive feline leukaemia virus infection in cats with lymphoma in Germany.

Progressive infection with feline leukaemia virus (FeLV) is considered one of the major risk factors for development of feline lymphoma. The aim of this study was to compare cats with lymphoma between 1980 and 1994 (first period) and between 1995 and 2009 (second period) concerning FeLV antigenaemia and age distribution. In addition, differences between FeLV antigen-positive and antigen-negative cats with lymphoma regarding patients' characteristics, tumour location and outcome were evaluated. There was a significant decrease in the percentage of lymphoma cases associated with progressive FeLV infection from the first (59 per cent) to the second (13 per cent) observation period. FeLV antigen-positive cats were significantly younger (median 3.7 v 11.3 years), and had significantly shorter response duration (median 25 days v 472 days) with therapy. In the cats of the second period, gastrointestinal and extranodal lymphomas were the most common anatomical sites, and the majority of those cats were FeLV antigen-negative. Thus, other aetiologies than progressive FeLV infection must have a greater impact on cancerogenesis among affected cats with lymphoma to date.

A randomized trial investigating the efficacy and safety of water soluble micellar paclitaxel (Paccal Vet) for treatment of nonresectable grade 2 or 3 mast cell tumors in dogs.

BACKGROUND: Effective treatments for dogs with advanced stage mast cell tumors (MCT) remain a pressing need. A micellar formulation of paclitaxel (paclitaxel [micellar]) has shown promise in early-phase studies. HYPOTHESIS/OBJECTIVES: The objective was to demonstrate greater activity for paclitaxel (micellar) compared with lomustine. The null hypothesis was µ(p) = µ(L) (ie, proportion of responders for the paclitaxel [micellar] and lomustine groups, respectively). ANIMALS: Two hundred and fifty-two dogs with advanced stage nonresectable grade 2 or 3 MCT. METHODS: Prospective multicenter randomized double-blind positive-controlled clinical trial. The primary endpoint was confirmed overall response rate (CORR) at 14 weeks. A secondary endpoint, biologic observed response rate (BORR), also was calculated. Safety was assessed by the characterization and grading of adverse events (AE). RESULTS: Overall CORR (7% versus 1%; P = .048) and BORR (23% versus 10%; P = .012) were greater for paclitaxel (micellar) compared with lomustine. Paclitaxel (micellar)-treated dogs were 6.5 times more likely to have a confirmed response and 3.1 times more likely to experience a biologic observed response. The majority of AE with paclitaxel (micellar) were transient and clinically manageable. Twenty-seven dogs (33%) receiving lomustine were discontinued because of hepatopathy compared with 3 dogs (2%) receiving paclitaxel (micellar) (P < .0001; odds ratio 26.7). CONCLUSIONS AND CLINICAL IMPORTANCE: Paclitaxel (micellar)'s activity and safety profile are superior to lomustine. The addition of an active and novel taxane to the veterinary armamentarium could fill a substantial need and, as its mechanism of action and AE profile do not overlap with currently available TKI, its availability could lead to effective combination protocols.

A randomized controlled study into the efficacy and toxicity of pegylated liposome encapsulated doxorubicin as an adjuvant therapy in dogs with splenic haemangiosarcoma.

Safety and efficacy of pegylated liposome encapsulated doxorubicin (PL-DOX) was compared with free doxorubicin as an adjuvant monotherapy in dogs with splenic haemangiosarcoma after splenectomy in a randomized prospective clinical trial. A total of 17 dogs in each group were treated. No significant difference in survival between the two treatments was found. The calculated median overall survival time for the 34 dogs was 166 days [95% confidence interval (CI) 148-184]. The ½ year and one-year survival was 41.2% (95% CI 24.8-56.9) and 22.7% (95% CI 9.9-37.4), respectively. In dogs treated with PL-DOX, a desquamating dermatitis like palmar-plantar erythrodysesthesia (PPES) was seen in two dogs, while three other dogs showed anaphylactic reactions. Cardiotoxicity was not seen in either treatment groups.

Thirteen-week dose-intensifying simultaneous combination chemotherapy protocol for malignant lymphoma in dogs.

This prospective study aimed to record the toxicity profile of a dose-intensifying simultaneous chemotherapy (DISC) protocol for lymphoma in dogs. Remission rates and the duration of the protocol were also evaluated. Twenty-one dogs were studied. Diagnosis was based on cytological or histological assessments. The DISC protocol is a 13-week maintenance-free protocol. L-Asparaginase (400 iu/kg) was administered subcutaneously on day 1, followed by weekly simultaneous intravenous administration of vincristine (0.7 mg/m(2) = 100 per cent), cyclophosphamide (200 mg/m(2) = 100 per cent) and doxorubicin (30 mg/m(2) = 100 per cent) at a starting dose level of 33 per cent. Dose levels were given twice and then increased by 5 to 7 per cent if grade 0 or I toxicities were seen, to a maximum dose level of 60 per cent. Two dogs experienced a grade IV toxicity (asymptomatic neutropenia in one dog and sepsis in the other). Two episodes of asymptomatic grade III thrombocytopenia and one episode of neutropenia were recorded. Other toxic events were infrequent and mild. Only one dog required hospitalisation for less than 72 hours. Seventeen dogs (80.9 per cent) achieved complete remission, one (4.8 per cent) achieved partial remission, two (9.5 per cent) had stable disease and in one (4.8 per cent) disease progressed.

Retrospective study of 871 dogs with thrombocytopenia.

Eight hundred and seventy-one dogs with thrombocytopenia were divided into the following five categories: immune-mediated thrombocytopenia (49; 5.6 per cent), thrombocytopenia caused by disseminated intravascular coagulation (DIC) (52; 6.0 per cent), thrombocytopenia caused by miscellaneous disorders (222; 25.5 per cent), neoplasia-associated thrombocytopenia (244; 28 per cent) and inflammatory/infectious thrombocytopenia (304; 34.9 per cent). The incidence of thrombocytopenia among the hospital population was 6.7 per cent. The dogs with immune-mediated thrombocytopenia and thrombocytopenia caused by DIC had significantly (P<0.001) lower platelet counts (median 32.0 x 10(9)/l and 55.0 x 10(9)/l, respectively) than the dogs in the other three categories.

Associations between proteinuria, systemic hypertension and glomerular filtration rate in dogs with renal and non-renal diseases.

Proteinuria and systemic hypertension are well recognised risk factors in chronic renal failure (CRF). They are consequences of renal disease but also lead to a further loss of functional kidney tissue. The objectives of this study were to investigate the associations between proteinuria, systemic hypertension and glomerular filtration rate (GFR) in dogs with naturally occurring renal and non-renal diseases, and to determine whether proteinuria and hypertension were associated with shorter survival times in dogs with CRF. Measurements of exogenous creatinine plasma clearance (ECPC), urine protein:creatinine ratio (UPC), and Doppler sonographic measurements of systolic blood pressure (SBP) were made in 60 dogs with various diseases. There was a weak but significant inverse correlation between UPC and ECPC, a significant inverse correlation between SBP and ECPC and a weak but significant positive correlation between UPC and SBP. Some of the dogs with CRF were proteinuric and almost all were hypertensive. Neoplasia was commonly associated with proteinuria in the dogs with a normal ECPC. CRF was the most common cause leading to hypertension. In the dogs with CRF, hypertension and marked proteinuria were associated with significantly shorter survival times.

Intra-tumoral gene delivery of feIL-2, feIFN-gamma and feGM-CSF using magnetofection as a neoadjuvant treatment option for feline fibrosarcomas: a phase-I study.

Despite aggressive pre- or postoperative treatment, feline fibrosarcomas have a high relapse rate. In this study, a new treatment option based on immune stimulation by intra-tumoral delivery of three feline cytokine genes was performed. The objective of this phase-I dose-escalation study was to determine a safe dose for further evaluation in a subsequent phase-II trial. Twenty-five client-owned cats with clinical diagnosis of fibrosarcoma - primary tumours as well as recurrences - entered the study. Four increasing doses of plasmids coding for feIL-2, feIFN-gamma or feGM-CSF, respectively, were previously defined. In groups I, II, III and IV these doses were 15, 50, 150 and 450 microg per plasmid and a corresponding amount of magnetic nanoparticles. Two preoperative intra-tumoral injections of the magnetic DNA solution were followed by magnetofection. A group of four control cats received only surgical treatment. Side effects were registered and graded according to the VCOG-CTCAE scale and correlated to treatment. Statistical analyses included one-way anova, post hoc and Kruskal-Wallis tests. ELISA tests detecting plasma feIFN-gamma and plasma feGM-CSF were performed. One cat out of group IV (450 microg per plasmid) showed adverse events probably related to gene delivery. As these side effects were self-limiting and occurred only in one of eight cats in group IV, this dose was determined to be well tolerable. Altogether six cats developed local recurrences during a 1-year observation period. Four of these cats had been treated with dose IV. Regarding these observations, a subsequent phase-II trial including a representative amount of cats should be tested for the efficacy of dose IV as well as dose III.

Lack of GNB3 exon 9 polymorphism in primary hypertensive and normotensive dogs.

The 5500T allele variant of the C5500T single nucleotide polymorphism in the human G protein beta3 subunit (GNB3) has been reported to be associated with primary hypertension. In this study, the GNB3 gene of primary hypertensive and normotensive dogs was examined for an analogous nucleotide polymorphism associated with hypertension. The genomic GNB3 dna, with 10 exons and nine introns coding for 340 amino acids, is described. PCR product sequencing of the GNB3 exon 9 from 25 dogs (including five hypertensive animals) failed to detect any nucleotide polymorphism. In contrast to human beings, there was no polymorphism at either the analogous nucleotide or in the respective exon. Only the human hypertension-associated thymine was detected, regardless of whether the dogs were hypertensive or normotensive. Furthermore, examinations of 565 dogs of 85 distinct breeds for the presence of the human 5500C nucleotide at the analogous nucleotide side failed to detect a cytosine that is present with high allele frequency in normotensive man. Owing to the lack of allele variance, it is concluded that canine primary hypertension is not associated with a polymorphism at either the respective human hypertension-associated nucleotide site or in the entire exon.

Treatment of dogs with lymphoma using a 12-week, maintenance-free combination chemotherapy protocol.

BACKGROUND: Treatment of lymphoma in dogs by long-term chemotherapy has favorable results. However, the efficacy of short-term, maintenance-free treatment protocols on remission and survival times in dogs has not been determined. HYPOTHESIS: That treatment using a 12-week chemotherapy protocol would be associated with satisfactory treatment outcome in dogs with lymphoma. ANIMALS: 77 dogs with histologically or cytologically confirmed diagnosis of lymphoma. METHODS: Prospective clinical trial in which dogs were treated with a 12-week chemotherapy protocol consisting of L-asparaginase, vincristine, cyclophosphamide, doxorubicin, and prednisolone. RESULTS: Complete remission rate was 76.3%. Multivariate logistic regression analysis revealed that clinical substage (P = .006) and immunophenotype (P = .003) had a significant influence on the likelihood of a dog achieving complete remission. Median duration of first complete remission was 243 days (range 19-1,191 days). The 6-month, 1-year, and 2-year remission rates were 68%, 28%, and 16%, respectively. In the multivariate analysis of patient variables, immunophenotype (P = .022) revealed a significant influence on first remission duration. Toxicosis was mild with the exception of 1 treatment-associated death. CONCLUSIONS AND CLINICAL IMPORTANCE: In this group of dogs the 12-week maintenance-free chemotherapy protocol was well tolerated and had satisfactory results.