As one of the most aggressive cancers seen in dogs, hemangiosarcoma grows and spreads rapidly, often without showing clear signs until it’s quite advanced. What can dog owners do to prevent this cancer or catch it early? And if your dog receives a diagnosis, what does it mean? Research on hemangiosarcoma has expanded rapidly in the past five years, getting the veterinary community closer to answering pressing questions like these. Keep reading to learn all about hemangiosarcoma, the current research being conducted about it, and everything dog owners should know about this complex disease.
Hemangiosarcoma: What Every Dog Owner Needs to Know and Research Insights
In this video, Dr. Kelly Diehl from the Morris Animal Foundation has a conversation with Dr. Antonella Borgatti, Professor of Oncology at the University of Minnesota’s College of Veterinary Medicine. They discuss hemangiosarcoma in dogs, covering its signs, how it develops, the available treatments, and ongoing research.
Morris Animal Foundation is a nonprofit organization that fundraises cutting-edge research for the benefit of animals ranging from koalas to kangaroos. Explore other articles about Morris Animal Foundation’s impact on animal health here.
What Is Hemangiosarcoma?
Hemangiosarcoma is a type of cancer that originates from the cells that form blood and blood vessels in pets. It predominantly affects the spleen, but can also affect the heart, skin, and liver. In fact, it can even manifest in multiple places simultaneously, which contributes to its complexity.
By the numbers:
- Ranks among the most devastating dog cancers
- More than 50% of dogs with a hemangiosarcoma diagnosis die within 4–6 months, even with treatment
- Only 10% of dogs survive a year
- Represents 5% of all dog cancers
- Around 50,000 dogs are diagnosed yearly
- Affects various breeds, primarily older dogs
- Also observed in wolves and coyotes, and cats, albeit rarely
What Are Signs To Look Out For?
Unfortunately, hemangiosarcoma is a very insidious type of cancer that often develops quickly and under the radar. Typically, a dog will not show signs of the cancer or have much discomfort until a large tumor is identified on the physical exam, or a tumor mass ruptures, leading to life-threatening complications. That being said, here are some clinical signs that have been linked with hemangiosarcoma.
Clinical signs in dogs:
- Sudden collapse
- Pale gums
- Sudden weakness
- Fluid in abdomen
- Skin mass
What Treatment Strategies Currently Exist?
With the exception of hemangiosarcoma localized in the skin, the principle goal of hemangiosarcoma treatment is to remove a tumor which may be the source of a life threatening hemorrhage, or to slow down or delay the onset or spread and metastasis.
In other words, it is typically not possible to “cure” this cancer, and treatment options focus on extending the life expectancy of the animal and helping to slow the destruction of the cancer.
Emerging research, however, identifies distinct subtypes of the cancer with varying outcomes, including better survival rates. This means that there are some dogs that will receive a hemangiosarcoma diagnosis and will live for a long period of time with the disease. With more research, treatment options are constantly improving.
What Can Dog Owners Do To Prevent This Cancer?
Many dog owners understandably want to know how environment, diet, exercise, genetics, hormones, and other factors contribute to a dog’s likelihood of developing hemangiosarcoma. At this time, there is no definitive answer to these questions. Yet, getting at the bottom of these questions is precisely what the Morris Animal Foundation is hoping to do through sharing the data from their Golden Retriever Lifetime Study.
The Golden Retriever Lifetime Study
Since 2012, the Golden Retriever Lifetime Study has been tracking the lives of over 3,000 golden retrievers in order to help identify risk factors for cancers and other diseases in dogs. Now, after a decade of progress, the data collected from the participating dogs is ready to be studied.
Among all recorded dog fatalities, a striking 75% are linked to cancer, with nearly 70% of these cancer-related deaths specifically attributed to hemangiosarcoma.
Not only have these findings resulted in the launch of the Hemangiosarcoma Initiative—a multi-year, multi-million dollar commitment to researching hemangiosarcoma, but it means researchers can use the data from the Golden Retriever Lifetime Study to answer questions about preventing this cancer.
For example, researchers have lifetime data on dogs that eventually developed hemangiosarcoma, having tracked things like:
- housing situation
- food choices
- preventative medications they took
- vaccination status
- whether they were spayed or neutered
- what kind of carpet was in the house
- what kind of cooking fuel was used in the primary residence
- what type of water they drank
All of this data will help us get much closer to being able to identify preventative measures dog owners can take to protect their dogs from this devastating cancer.
What Are Some Common Misconceptions?
“Hemangiosarcoma Is a Death Sentence”
This is not true! Hemangiosarcoma does not have to be a death sentence. As researchers learn more about the disease, there are more and more treatments that can prevent euthanasia. Many people assume that a diagnosis means that the dog will not live very long. While it’s true that the majority will have a bad outcome, there are some dogs that will live a long time.
“Mortality Data Is Definitive”
Due to the problem of finances and the prevalence of early euthanasia, mortality data for hemangiosarcoma should be interpreted with a grain of salt. The data can be skewed due to the individual decisions that dog owners make regarding treatment. In many cases, dog owners can’t afford the more expensive treatments that could lead to a longer lifespan for their pet. Early euthanasia decisions can make survival times shorter, and can make it more difficult for vets to learn from new treatments.
“You Can Just Remove The Spleen”
If the cancer is most commonly detected in the spleen, some dog owners ask—Why not just remove the spleen? Vets do not advocate for the removal of the spleen in situations where dog owners are concerned about hemangiosarcoma formation in a breed that is considered to be at risk or the presence of hemangiosarcoma before a mass forms. This is because hemangiosarcoma often localizes in multiple organs at the same time, and so it would not be beneficial.
“It’s Just One Cancer”
Hemangiosarcoma is actually more of a complex of diseases instead of just one disease. So the more we learn about the differences between all of the subtypes, hopefully with time we will be able to develop more targeted therapeutic strategies that will have better outcomes.
“Alternative Treatments Are Effective”
No! Researchers strongly discourage people from using supplements to treat hemangiosarcoma. Anecdotal evidence may not be accurate, and can give people false hope. In the worst case scenario, the use of supplements could be detrimental, causing interactions with medications.
The Future of Hemangiosarcoma Research
We hope this helped answer some of your questions about hemangiosarcoma. At the end of the day, hemangiosarcoma is a devastating cancer in pets, but with the combined force of the Golden Retriever Lifetime Study and the Hemangiosarcoma Initiative, there is hope in the veterinary community that answers, breakthroughs, and new treatments will be available hopefully in the next few years. In the meantime, keep tabs on Morris Animal Foundation for breaking news on hemangiosarcoma research!