Radiation Therapy for the Management of Cardiac Hemangiosarcoma in Dogs
Hemangiosarcoma (HSA) is a common and devastating disease in dogs; cardiac HSA (CHSA) is a common variant for which accessible treatments are particularly lacking. Unique vascular biology suggests that high dose single fraction radiation therapy (HDSF RT) should be particularly useful in this disease setting. The primary goal of the planned pilot study is to determine how the activity of HDSF RT against CHSA is clinically manifested. To accomplish this, we will randomize dogs to be treated with RT or mock RT (placebo) in a blinded manner, and quantify changes in tumor volume, frequency and timing of recurrent cardiac tamponade (blood on the heart), and overall survival time. This information will guide use of various outcome measures in future studies. To that end, we hypothesize that HDSF RT will cause tumor volume and frequency of recurrent tamponade to decrease, and overall survival time to increase as compared with unirradiated control subjects. Secondary goals of this study are to (1) collect blood samples before and after RT in effort to develop biomarkers of the tumor response to RT into predictive and prognostic assays, and (2) evaluate means for making such RT more widely accessible to veterinary clientele.
Study Procedure and Requirement:
- Your dog must be hospitalized and anesthetized to undergo a CT (CAT) scan for additional staging and radiation therapy planning.
- Your dog will be randomized into one of two groups; dogs in both groups will be briefly anesthetized the next day, for treatment with either (1) RT or (2) mock RT, also known as a placebo. Dogs in both treatment groups will receive the same follow-up.
- Once recovered from anesthesia on the second day, your dog should be able to go home.
- Blood samples will be collected before and 24 hours after treatment. A brief recheck appointment must be scheduled at NCSU for the 24 hour collection.
- Recheck appointments must be scheduled at NCSU, 4 and 12 weeks after treatment. A CT scan will be performed at both visits. This will allow us to see if the tumor has gotten smaller in response to treatment.
- Follow up exams with either your cardiologist or the emergency room veterinarian should be pursued if your dog displays signs consistent with additional bleeding of the tumor (weakness, lethargy and/or fainting). See "Financial Incentive" regarding the cost of these possible additional procedures.
- Additional information may be collected by periodic phone calls to you or your primary care veterinarian.
- Dogs with an echocardiogram (sonogram of the heart) showing evidence of CHSA, as well as bloody effusion from a pericardial tap will be considered for the study.
- Participating dogs must be otherwise healthy and free of spread of the disease at the time of diagnosis as characterized by a physical examination, routine lab work (complete blood count, and serum chemistry panel) and diagnostic imaging (chest x-rays and an abdominal ultrasound).
- Dogs may not receive other treatments for their CHSA, including chemotherapy, homeopathic, or alternative therapies (such as Yunnan Baiyao) prior to or during enrollment in this study.
- NCSU will pay for the initial CT scan, radiation planning, therapy, and associated anesthesia. A value of about $1500, without the support of this clinical trial.
- We will also cover the cost of the recheck CT scans and associated anesthesia at 4 and 12 weeks after therapy. A value of about $1300, without the support of this clinical trial.
- For the first 3 months after enrolling in this study, the clinical trial will cover the cost of a brief echocardiogram, pericardial tap and evaluation of the fluid removed during the tap, if your veterinarian suspects recurrent pericardial tamponade, and the work-up is performed at NCSU. An approximately $175 value without the support of this clinical trial. We will provide up to $100 for these procedures if performed elsewhere.
- The study will contribute up to $500 for treatment of unexpected complications directly associated with radiation therapy. Care for side effects must be provided at NCSU, under the guidance of a radiation oncologist.
Page last updated December 30, 2013