Stay informed of the latest progress in canine health research.
We need your support to fund research that helps dogs live longer, healthier lives.
By G. Elizabeth Pluhar, D.V.M., Ph.D., Dip ACVS1, John R. Ohlfest, Ph.D.2, and Matthew A. Hunt, M.D.
1Department of Veterinary Clinical Sciences, College of Veterinary Medicine; 2Department of Pediatrics, School of Medicine; 3Department of Neurosurgery, School of Medicine
Meningiomas are the most common brain tumor in dogs. Surgical removal is the mainstay of treatment, and most of these tumors are managed with local therapy. Historically, the survival time of dogs with meningiomas treated with surgery alone has been four and one-half to seven months. Systemic therapies so far have had limited effectiveness. However, based on preclinical data from our research program, we embarked on the development of anti-tumor vaccinations to treat dogs with spontaneous meningiomas after surgical removal.
Thirteen dogs have been treated with surgical removal of the tumor followed by a series of vaccinations made from the dog’s own tumor cells (called an “autologous tumor lysate” vaccine), along with one of two immune stimulators. The vaccines were injected into the skin on the back of the dog’s neck two weeks after surgery at suture removal. A total of six vaccinations were given at two-week intervals. All 13 dogs have completed the vaccination series.
Magnetic resonance imaging (MRI) of the brain was performed immediately after surgery to assess whether the tumor mass was completely removed, and 3, 6, and 12 months after surgery to check for tumor recurrence. Blood collected from each dog during the visits for the MRIs was analyzed for an immune response against the tumor. High-grade malignant tumors were found in two dogs, and low-grade tumors were found in the remaining 11 dogs.
A survival analysis comparing dogs treated with surgery and vaccines to dogs that had surgical removal alone demonstrated a significant survival improvement in the dogs receiving the vaccine therapy. To date, the mean survival time in dogs treated with surgery and vaccines is about one year, with many of the treated dogs still alive and tumor-free, compared to a survival time of approximately 200 days in dogs treated with surgery alone. We also have not seen severe toxicities or side effects in the vaccine-treated dogs. Immune testing demonstrated an antibody response as well as enhanced tumor cell killing by the treated dogs’ lymphocytes.
Our results indicate that immunotherapy using autologous tumor lysate and immune adjuvant after tumor removal elicits specific immune responses against residual tumor cells and increases survival over historical controls. Since this therapy appears to work so well in dogs with meningiomas, it may also be effective in humans with meningiomas that have failed to respond to the standard therapy or are at high risk of recurrence.
Although the pilot phase for this trial is complete and we are not currently recruiting dogs with meningiomas, we are waiting to hear whether two grant proposals to continue our work on dogs with meningiomas will be funded. Check the CVM Clinical Investigation Center website at www.cvm.umn.edu/cic/current/ braintumortrials for more information, applications to enroll dogs in clinical trials, or to make a contribution to support this research.
In this podcast we are wrapping up our “Old Dogs Rule” educational series with a difficult, but important conversation about end of life care. We are very fortunate to feature Dr. Kathleen Cooney, founder of “Home to Heaven,” an in-home pet hospice and euthanasia services practice. She is also the owner of the first-ever pet euthanasia center in the United States. The center is located on her 35-acre farm in Loveland, Colorado and offers two comfort rooms for pet euthanasia. It is open year-round for families looking for an alternative to standard clinic or in-home euthanasia. Dr. Cooney graduated from the Colorado State University College of Veterinary Medicine in the spring of 2004. That same spring, her family had to say goodbye to their 15-year-old yellow lab, McKenzie. McKenzie passed peacefully under the aspen tree in their front yard. From this experience, Dr. Cooney learned just how important it was for pets to be at home for the end of their lives. In 2012, she completed writing the book “Veterinary Euthanasia Techniques: A practical guide.” Dr. Cooney served on the 2013 American Veterinary Medical Association's panel on euthanasia guidelines. She is currently the Vice President and conference coordinator for the International Association for Animal Hospice and Palliative Care (IAAHPC). She travels frequently to speak on her work and on the current advancements in end-of-life care.
This podcast was made possible thanks to the generous support of the Kenneth A. Scott Charitable Trust, A KeyBank Trust.