Investigation of the immunostimulatory response of mechanical high intensity focused ultrasound (histotripsy) on naturally-occurring solid tumors


To determine if histotripsy, a novel treatment that can destroy tissue without radiation or heat, can effectively treat canine soft tissue sarcomas.


Solid tumors (including soft tissue sarcomas and mast cell tumors) of the skin are a common form of cancer in dogs. They can invade tissues that are vital to normal function, and complete, curative surgical removal can be impossible without amputation or radiation therapy. In some cases, a tumor may be surgically resectable, but it could still recur at the surgical site or in a distant site like lymph node or lung.

Histotripsy is a novel treatment that mechanically breaks down tissues and can potentially induce the immune system to attack cancer cells. This study aims to evaluate the efficacy of histotripsy to treat dogs with soft tissue sarcomas, to ultimately advance the development of histotripsy as a non-surgical treatment option and an immunotherapy treatment against metastatic disease.

This study is funded by the Focused Ultrasound Foundation.


  • Dogs of any age, weight, sex, or breed diagnosed with a malignant, solid soft tissue tumor that is at least 2 cm in diameter.
  • Owners have elected standard-of-care treatment for soft tissue sarcoma – i.e. surgical removal.
  • Free from serious systemic illness.
  • Life expectancy of at least six weeks.


  • Dogs who have received any tumor-directed therapy (e.g. radiation) or immunosuppressive drugs within four weeks prior to study enrollment.
  • Dogs who have received chemotherapy within three weeks prior to study enrollment

Study Design

The treatment will require three (3) CT scans and two (2) surgical procedures. If your dog meets the eligibility criteria, your dog will be scheduled for a CT scan of the tumor and a surgical biopsy under general anesthesia. The CT scan will also include the thorax and abdomen if not performed at the screening visit. The biopsy includes removing a small sample of the tumor to determine its specific type and for later baseline gene expression. Urine sample, and blood samples for CBC and chemistry will be repeated to evaluate overall health, and additional blood for later baseline measurement of immune cell signals will be taken.

Within ten (10) days of the biopsy, your dog will be scheduled for the histotripsy treatment followed by another CT scan of the tumor. Histotripsy will be applied to the tumor under general anesthesia. Histotripsy treatment will occur on the Blacksburg campus. The histotripsy treatment is expected to take 30 minutes to an hour, but may take longer for some patients. Your dog will be recovered from the procedure and is expected to be sent home the same day. Due to timing and for the safety of your pet, s/he may need to stay overnight while recovering from anesthesia. Your dog will need to return to the Animal Cancer Care and Research Center in Roanoke the following day for a CT scan of the tumor, and s/he will be sent home following the scan.

The final surgery to remove the tumor will take place 4-6 days after treatment. A CT scan of the tumor will be performed prior to removal. The removal will be performed or supervised by a board-certified veterinary surgeon that has undergone additional training in cancer surgery. Your dog will recover and be discharged as is standard for patients, based on surgeon discretion.

Your dog will need to return to the Oncology service in Roanoke 2 weeks after the definitive surgery, as part of the follow up after tumor resection and suture removal. At the recheck visit, your pet will have a physical exam, and additional diagnostics if indicated.


Once your dog is enrolled, the study will cover the expenses for the subsequent lab-work, CT images, tumor biopsy and histopathology, the histotripsy treatment, the hospital stay and associated costs, and will cover up to $3,000 of the cost of definitive surgery.

You are responsible for any clinical fees for surgery exceeding $3,000 and any fees associated with medical complications of the histotripsy therapy or other medical problems. The recheck and screening visits are not covered by the study. Your total out of pocket costs for the study, including the screening and recheck visits, are estimated to be between $350 and $2000.


Mindy Quigley, Clinical Trials Coordinator
Office Phone: 540-231-1363 | Email:

Dr. Shawna Klahn, Oncology
Phone: 540-526-2300 | Email:

If your query is urgent, please call the Animal Cancer Care and Research Center on 540-526-2300.