An adult female spayed dog was evaluated after inadvertently receiving a total dose of 1,750 mg oral cyclophosphamide, equivalent to 2,303 mg/m, over 21 days (days -21 to 0). Nine days after the last dose of cyclophosphamide (day +9), the dog was evaluated at Perth Veterinary Specialists. Physical examination revealed mucosal pallor, a grade 2/6 systolic heart murmur, and severe hemorrhagic cystitis. Severe nonregenerative pancytopenia was detected on hematology. Broad spectrum antibiotics, two fresh whole blood transfusions, granulocyte colony stimulating factor, and tranexamic acid were administered. Five days after presentation (day +14), the peripheral neutrophil count had recovered, and by 12 days (day +21) the complete blood count was near normal. A second episode of thrombocytopenia (day +51) was managed with vincristine, prednisolone, and melatonin. The dog made a complete recovery with no long-term complications at the time of writing. To the author's knowledge, this is the highest inadvertently administered dose of cyclophosphamide to result in complete recovery.

Lomustine, vincristine, procarbazine and prednisolone (LOPP) chemotherapy has been suggested to be an effective treatment for dogs with naïve non-indolent T-cell lymphoma (TCL). Studies evaluating prognostic factors for dogs with TCL treated with LOPP chemotherapy are lacking. The aim of this retrospective study was to assess potential prognostic factors for canine naïve non-indolent TCL treated with the LOPP protocol. This was a retrospective cohort study of naïve non-indolent TCL treated with the LOPP chemotherapy protocol at a single specialty veterinary oncology clinic. Sixty-seven dogs met the inclusion criteria. The outcomes assessed included progression free survival (PFS), overall survival time (OST) and duration of complete response (DCR). The overall median PFS was 118 days (range 7-2302 days). The median OST was 202 days (range 8-2302 days). The overall median DCR was 316 days (range 38-2261 days). Number of treatments administered (p < .0001), multicentric disease (p = .044) and the presence of hypercalcaemia (p = .006) were prognostic indicators for PFS. Increasing number of treatments (p < .0001) and age (p = .0088) were prognostic indicators for OST. To our knowledge, this is the first study to describe hypercalcaemia as a positive prognostic indicator of PFS for TCL treated with LOPP chemotherapy.LOPP chemotherapy can be considered as a first-line treatment protocol against naïve hypercalcaemic non-indolent TCL.

Thrombocytopenia is commonly encountered in veterinary oncology. Currently, there are no standard guidelines regarding the administration of chemotherapy to the patients with thrombocytopenia. This observational epidemiological cohort study aimed to determine whether thrombocytopenic dogs were at increased risk of gastrointestinal adverse effects (vomiting, diarrhoea, inappetence) or haemorrhage following administration of standard doses of chemotherapy. The adverse effects following 77 prospectively identified episodes of thrombocytopenia (platelet count, <200 000 µL ) were compared with the adverse effects experienced in a retrospective cohort (platelet count >200 000 µL ), and evaluated by statistical analysis. Overall, there was no statistically significant difference in the incidence of gastrointestinal adverse effects or haemorrhage between thrombocytopenic and control dogs. The control group of dogs with lymphoma were statistically more likely to experience vomiting as an adverse effect of chemotherapy (P = 0.028). The results presented here showed no evidence for an increased risk of gastrointestinal adverse effects or haemorrhage in thrombocytopenic dogs after receiving standard doses of chemotherapy.

Human and canine sarcomas are difficult to treat soft tissue malignancies with an urgent need for new improved therapeutic options. Local recurrence rates for humans are between 10%–30%, and 30%–40% develop metastases. Outcomes for dogs with sarcoma vary with grade but can be similar. Pet dogs share the human environment and represent human cancer with genetic variation in hosts and tumours. We asked if our murine studies using genetically identical mice and cloned tumour cells were translatable to larger, genetically diverse domestic dogs with naturally occurring tumours, to (i) develop a canine cancer therapeutic, and (ii) to use as a translational pathway to humans. Our murine studies showed that intra‐tumoral delivery of interleukin‐2 (IL‐2) plus an agonist anti‐CD40 antibody (Ab) induces long‐term curative responses ranging from 30% to 100%, depending on tumour type. We developed an agonist anti‐canine‐CD40 Ab and conducted a phase I dose finding/toxicology 3 + 3 clinical trial in dogs (n = 27) with soft tissue sarcomas on account of suitability for intratumoral injection and straightforward monitoring. Dogs were treated with IL‐2 plus anti‐CD40 antibody for 2 weeks. Three dose levels induced tumour regression with minimal side effects, measured by monitoring, haematological and biochemical assays. Importantly, our mouse and canine studies provide encouraging fundamental proof‐of‐concept data upon which we can develop veterinary and human immunotherapeutic strategies.

Immunohistochemistry on FF-PE blood clots offers clinicians a reliable, inexpensive and minimally invasive method of phenotyping neoplastic cells in circulation. Compared to other available methods, prolonged sample stability allowing for transport and retrospective examination is a distinct advantage. This technique should be considered a useful adjunct to the currently available methods for the phenotypic evaluation of lymphoid leukaemia in dogs.