Evaluation of a targeted anti-αβ integrin near-infrared fluorescent dye for fluorescence-guided resection of naturally occurring soft tissue sarcomas in dogs.

Purpose: Complete resection is a key prognostic factor for survival in patients with soft tissue sarcoma (STS), in humas and companion animals alike. Fluorescence-guided surgery could improve resection accuracy. As dogs are frequently affected by STS, they serve as a model to test an anti-αβ integrin targeting near-infrared fluorescent (NIRF) dye (Angiostamp800) for fluorescence-guided surgery in STS to evaluate its safety and feasibility in dogs, and if it translates into a clinically relevant benefit compared to the standard of care with regards to completeness of surgery and local recurrence.

Relationship between radiation dose and cerebral microbleed formation in dogs with intracranial tumors.

Background: Cerebral microbleeds (CMBs) are a possible sequela in human brain tumor patients treated with radiation therapy (RT). No such association is reported in dogs.

Objectives: To investigate whether CMBs occur in dogs after radiotherapy, and if there is an association between number and dose, and an increase over time.

Stereotactic Radiation Therapy Planning, Dose Prescription and Delivery in Veterinary Medicine: A Systematic Review on Completeness of Reporting and Proposed Reporting Items.

Increasing numbers of dogs and cats with cancer are treated with stereotactic radiosurgery, stereotactic radiation therapy or stereotactic body radiotherapy (SRS, SRT or SBRT). We provide a systematic review of the current data landscape with a focus on technical and dosimetric data of stereotactic radiotherapy in veterinary oncology. Original peer-reviewed articles on dogs and cats with cancer treated with SRT were included.

Radiation toxicity grading after chemoradiotherapy of canine urinary tract carcinomas: Comparing VRTOG to VRTOG_v2.0.

Radiation toxicities may be underestimated after treatment of transitional cell carcinoma in dogs' lower urinary tract. Assessing acute and late toxicities and differentiating them from progressive disease (PD) impacts further therapeutic approach. We retrospectively assessed dogs treated with definitive-intent chemoradiotherapy (12 × 3.

Risk adaptive planning with biology-based constraints may lead to higher tumor control probability in tumors of the canine brain: A planning study.

Background: Classical radiation protocols are guided by physical dose delivered homogeneously over the target. Protocols are chosen to keep normal tissue complication probability (NTCP) at an acceptable level. Organs at risk (OAR) adjacent to the target volume could lead to underdosage of the tumor and a decrease of tumor control probability (TCP).

Triple combination of lomustine, temozolomide and irradiation reduces canine glioma cell survival in vitro.

Background: Combined chemoradiation offers a promising therapeutic strategy for dogs with glioma. The alkylating agents temozolomide (TMZ) and lomustine (CCNU) penetrate the blood-brain barrier, and doses for dogs are established. Whether such combinations are clinically advantageous remains to be explored together with tumour-specific markers.

A shortened whole brain radiation therapy protocol for meningoencephalitis of unknown origin in dogs.

Introduction: A variety of treatment options have been described for canine meningoencephalitis of unknown origin (MUO). Few studies focused on radiation therapy as a second line immunomodulating treatment, implicating its effective use. However, a standard radiation therapy protocol is lacking, and further research will help to evaluate the effect of different dose regimens.

Comparison of alfaxalone and propofol on haematological and serum biochemical variables in cats undergoing radiotherapy with sevoflurane maintenance.

Objective: To evaluate effects of repeated alfaxalone or propofol administration on haematological and serum biochemical variables in cats undergoing radiotherapy.

Study Design: Prospective, block-randomized, clinical trial.

Animals: A group of 39 client-owned cats.

Elevated circulating Hsp70 levels are correlative for malignancies in different mammalian species.

Circulating Hsp70 levels were determined in feline and porcine cohorts using two different ELISA systems. These comparative animal models of larger organisms often reflect diseases, and especially malignant tumors, better than conventional rodent models. It is therefore essential to investigate the biology and utility of tumor biomarkers in animals such as cats and pigs.

A concept for anisotropic PTV margins including rotational setup uncertainties and its impact on the tumor control probability in canine brain tumors.

In this modelling study, we pursued two main goals. The first was to establish a new CTV-to-PTV expansion which considers the closest and most critical organ at risk (OAR). The second goal was to investigate the impact of the planning target volume (PTV) margin size on the tumor control probability (TCP) and its dependence on the geometrical setup uncertainties.

Treatment of intracranial neoplasia in dogs using higher doses: A randomized controlled trial comparing a boosted to a conventional radiation protocol.

Background: Local progression of intracranial tumors can be the consequence of insufficient radiation dose delivered. Dose increases in the brain must be made carefully so as not to risk debilitating adverse effects such as radiation necrosis.

Hypothesis: A new protocol with 10 × 4 Gy + 11% physical dose increase limited to the macroscopic tumor volume results in a clinically better outcome compared to a 10 × 4 Gy protocol.

Relative tumor volume has prognostic relevance in canine sinonasal tumors treated with radiation therapy: A retrospective study.

Tumor volume is controversially discussed as a prognostic factor in dogs treated with radiation therapy for sinonasal tumors. Dogs' body sizes vary widely and relative rather than absolute tumor volume might provide better prognostic information. Our hypothesis was that relative rather than absolute tumor volume (gross tumor volume, GTV) influences time to progression (TTP) and that a larger tumor volume is correlated with a higher tumor stage.

Dose- and Volume-Limiting Late Toxicity of FLASH Radiotherapy in Cats with Squamous Cell Carcinoma of the Nasal Planum and in Mini Pigs.

Purpose: The FLASH effect is characterized by normal tissue sparing without compromising tumor control. Although demonstrated in various preclinical models, safe translation of FLASH-radiotherapy stands to benefit from larger vertebrate animal models. Based on prior results, we designed a randomized phase III trial to investigate the FLASH effect in cat patients with spontaneous tumors.

Dose-escalated simultaneously integrated boost radiation protocol fails to result in a survival advantage for sinonasal tumors in dogs.

The prognosis for canine sinonasal tumors remains rather poor despite definitive-intent radiotherapy (RT). Theoretical calculations predicted improved outcomes with simultaneously integrated boost (SIB) protocols. With the hypothesis of clinically detectable differences in outcome between groups, our retrospective study evaluated prognostic variables and outcome in dogs treated with regular versus SIB RT.

Diagnosis and radiation therapy of an extensive myxoma in the retropharyngeal region infiltrating the cranial cervical vertebral canal in a dog.

An 8-year-old, intact Rottweiler-female dog presented due to an acute onset of lethargy, abnormal gait, and wheezing. Physical examination revealed stridor, cervical pain, and ambulatory tetraparesis. Magnetic resonance imaging-examination displayed a lobulated, fluid-filled mass extending from the sphenoid bone to C5, infiltrating the cranial vertebral canal causing extradural compression of the spinal cord and narrowing of the pharynx.

Can volumetric modulated arc radiation therapy reduce organ at risk dose in stage 4 sinonasal tumors in dogs treated with boost irradiation?

Intensity modulated radiation therapy (IMRT) introduced marked changes to cancer treatment in animals by reducing dose to organs at risk (OAR). As the next technological step, volumetric modulated arc therapy (VMAT) has advantages (increased degrees-of-freedom, faster delivery) compared to fixed-field IMRT. Our objective was to investigate a possible advantage of VMAT over IMRT in terms of lower OAR doses in advanced-disease sinonasal tumors in dogs treated with simultaneously-integrated boost radiotherapy.

Canine presumed glial brain tumours treated with radiotherapy: Is there an inferior outcome in tumours contacting the subventricular zone?

Post-treatment outcome in canine glial tumours is described with a broad range of survival times between 2 and 28 months. After surgery or radiation therapy, the tumours may progress locally or spread within the central nervous system. It is unknown if tumour- or patient-specific factors influence prognosis.

Retrospective assessment of radiation toxicity from a definitive-intent, moderately hypofractionated image-guided intensity-modulated protocol for anal sac adenocarcinoma in dogs.

A recent calculation study predicted acceptable toxicity in pelvic organs at risk for a new definitive-intent, moderately hypofractionated radiation therapy (RT) protocol (12 x 3.8 Gy), when used with image-guided intensity-modulated radiation therapy (IG-IMRT). We hypothesized this protocol to result in clinically acceptable radiation toxicities.

A Novel Analytical Population Tumor Control Probability Model Includes Cell Density and Volume Variations: Application to Canine Brain Tumor.

Purpose: Tumor control probability (TCP) models based on Poisson statistics characterize the distribution of surviving clonogens. Thus enabling the calculation of TCP for individuals. To mathematically describe clinically observed survival data of patient cohorts it is necessary to extend the Poisson TCP model.

Estimation of planning organ at risk volumes for ocular structures in dogs undergoing three-dimensional image-guided periocular radiotherapy with rigid bite block immobilization.

Planning organ at risk volume (PRV) estimates have been reported as methods for sparing organs at risk (OARs) during radiation therapy, especially for hypofractioned and/or dose-escalated protocols. The objectives of this retrospective, analytical, observational study were to evaluate peri-ocular OAR shifts and derive PRVs in a sample of dogs undergoing radiation therapy for periocular tumors. Inclusion criteria were as follows: dogs irradiated for periocular tumors, with 3D-image-guidance and at least four cone-beam CTs (CBCTs) used for position verification, and positioning in a rigid bite block immobilization device.

Reducing margins for abdominopelvic tumours in dogs: Impact on dose-coverage and normal tissue complication probability.

Image-guided, intensity modulated radiation therapy (IG-IMRT) reduces dose to pelvic organs at risk without losing dose coverage to the planning target volume (PTV) and might permit margin reductions potentially resulting in lower toxicity. Appropriate PTV margins have not been established for IG-IMRT in abdominopelvic tumours in dogs, and herein we explore if our usual PTV 5 mm margin can be reduced further. Datasets from dogs that underwent IG-IMRT for non-genitourinary abdominopelvic neoplasia with 5 mm-PTV expansion were included in this retrospective virtual study.