Definitive-intent uniform megavoltage fractioned radiotherapy protocol for presumed canine intracranial gliomas: retrospective analysis of survival and prognostic factors in 38 cases (2013-2019).

BACKGROUND: Radiotherapy (RT) is currently considered the treatment of choice for presumed canine intracranial gliomas. However, variable therapeutic responses are described, due to heterogeneous populations and different radiation methods or protocols. Only one study dedicated to intracranial suspected glioma highlighted prognostic criteria. Determination or confirmation of specific clinical and imaging prognostic factors may guide the therapeutic management of these tumours. The objectives were to provide data on long-term clinical outcome (including quality of life, QoL) and to determine specific prognostic factors associated with survival time. We report a single-institution retrospective study, including all dogs with suspected symptomatic primary solitary intracranial glioma, treated with a complete uniform fractionated megavoltage radiation protocol of 15x3Gy over 5 weeks, between January 2013 and February 2019. Thirty-eight client-owned dogs were included. Medical records were retrospectively evaluated for median overall survival time (MST), clinical and imaging responses. Prognostic factors on survival were researched in terms of signalment, clinical presentation, tumour imaging characteristics and response following RT. Finally, the RT's impact on the dogs' clinical signs and Qol were evaluated by the owners. RESULTS: The disease-specific MST was 698 days (95% CI: 598-1135). Survival at 1 and 2 years were respectively 74.2 ± 7.4% and 49.0 ± 9.8%. Initial clinical signs were related to survival, as well as tumour characteristics such as cystic-pattern, mass effect and Tumour/Brain volume ratio. No significant adverse effect or radiotoxicity was observed. CONCLUSIONS: RT appears as a safe and effective treatment for canine intracranial gliomas, allowing long-term tumour control, improvement of life's quality and management of associated clinical signs. The initial clinical signs and MRI characteristics (Tumour/Brain volume ratio, cyst-like lesion and mass effect) may help predict the prognosis.

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.

Use of preoperative computed tomography for surgical treatment of recurrent draining tracts.

OBJECTIVES: To evaluate a rational decision-making approach based on preoperative computed tomography for surgical planning in dogs and cats with recurrent draining tracts. METHODS: Retrospective evaluation of case records of animals that underwent preoperative computed tomography for surgical treatment of thoracic/abdominal recurrent draining tracts. Cases were classified according to whether a source of inflammation and/or infection, in particular foreign bodies, was identified (group 1), suspected (group 2) or neither identified nor suspected (group 3) at computed tomography. Surgery consisted of removal of the source of inflammation and/or infection (group 1), debridement or abscess drainage (group 2) or en bloc resection of diseased tissues (group 3). Clinical outcome was evaluated at least 12 months after surgery. RESULTS: A source of inflammation and/or infection was found in 100% (8 of 8), 41% (7 of 17) and 25% (3 of 12) of cases in groups 1, 2 and 3, respectively. Recurrent draining tracts resolved in 100% (8 of 8), 94% (16 of 17) and 92% (11 of 12) of cases in groups 1, 2 and 3, respectively. CLINICAL SIGNIFICANCE: The proposed strategy provided a 95% (35 of 37) cure rate, after a single procedure in 81% (30 of 37) of cases. Recovery of a foreign body at surgery was not a prerequisite for the resolution of the recurrent draining tracts.

Clinical vignette Fortuitous diagnosis of a persitent left cranial vena by color flow Doppler echocardiography in a dog.

A persistent left cranial vena cava is described in an asymptomatic three-year-old female Shi Tzu. The purpose of this report is to show the value of color flow Doppler echocardiography in the diagnosis of this uncommon congenital cardiovasular abnormality.