# Extended Survival in a Dog with Primary Bone Hemangiosarcoma Following Treatment with Neoadjuvant Oncolytic Virotherapy and Standard of Care

## TL;DR

A dog with bone cancer survived over seven years after receiving oncolytic virus therapy, amputation, and chemotherapy.

## Contribution

This is the first reported case of oncolytic virotherapy used in a dog with primary bone hemangiosarcoma.

## Key findings

- The dog survived more than seven years after treatment with oncolytic virus therapy, amputation, and chemotherapy.
- Histopathology confirmed the diagnosis of intramedullary hemangiosarcoma following virotherapy and amputation.

## Abstract

Malignant bone cancer carries a grave prognosis in dogs despite treatment with surgery and chemotherapy. Neoadjuvant systemic oncolytic virus therapy has the potential to improve outcomes in some patients by stimulating an anti-tumor immune response. This case report presents extended survival in a five year old mixed-breed dog with primary bone hemangiosarcoma (HSA) treated with oncolytic virus therapy, amputation, and chemotherapy. According to the reviewed literature, this is the first reported case of a dog with HSA of the bone treated with oncolytic virus therapy.

A three year old male neutered mixed breed dog presented with a mass on the right carpus and accompanying lameness. A Jamshidi bone biopsy was performed, and histopathology results were consistent with a sarcoma. The dog received oncolytic virotherapy (OV) with vesicular stomatitis virus (VSV) as part of a clinical trial in dogs with osteosarcoma (OSA). Ten days after VSV treatment, the affected limb was amputated, and histopathology was consistent with intramedullary HSA. Considering the new diagnosis, standard doxorubicin chemotherapy was prescribed. With this combination of therapies, the dog had an extended survival of more than seven years and remains alive at the time of writing. This is the first case report documenting OV given in conjunction with the standard of care for canine appendicular HSA.