When to Euthanize a Dog with Hemangiosarcoma [By Dr Crow]

This article was updated on July 1st, 2022

Making the decision to euthanize a dog with hemangioscarcoma / spleen tumors can be challenging. It’s a decision that I had to grapple with recently with the owner of Rusty, a 12-year-old black Labrador retriever, who was brought to our clinic.

On the day Rusty was brought in to see me, he had become particularly tense, reactive to anyone touching his tummy. I was concerned, especially at the rate at which Rusty had deteriorated; for a dog that used to rush into the vets out of excitement, he was very flat and avoided walking at all costs.

Blood tests showed a high level of globulins (a type of protein often associated with cancer), high liver enzymes and a mild anaemia. We suspected the worst – hemangiosarcoma was a potential diagnosis and an ultrasound scan of Rusty’s abdomen was offered to help confirm this. The scan showed free fluid within Rusty’s abdomen which turned out to be blood and an enlarged irregular mass on his spleen.

Unfortunately, Rusty had a splenic hemangiosarcoma (spleen tumor) which was bleeding into his abdomen. The tumor had aggressively infiltrated much of the surrounding tissues, including the liver. Because of this, euthanasia was recommended.

Surgery in such cases carries a poor prognosis, and while the offer was made to go to surgery to the owners, they agreed that it wasn’t fair to put him through such a procedure. Rusty had lived a wonderful life up until this point and putting him to sleep was the most humane thing we could do for him.

A sudden decision

If your dog has been recently diagnosed with hemangiosarcoma then aspects of Rusty’s story might seem familiar. It can be hard to decide when to continue treatment and when to put your beloved companion to sleep. Hemangiosarcoma often lies under the radar until it has progressed to a very late stage of the disease, leaving many owners with a sudden decision of whether to euthanize their dog. Having such an ultimatum sprung upon them is very hard for any dog parent.

In this article, I will outline key information to help you decide when it is the right time to euthanize a dog with hemangiosarcoma, including survival rates for dogs with different types of hemangiosarcoma, treatment options, and finally, important questions to consider and steps to take before euthanizing a dog with hemangiosarcoma. Hopefully, this will give you enough information to be able to make an informed decision.

What is a hemangiosarcoma?

Hemangiosarcoma, or HSA for short, is a highly malignant cancer of a type of cell known as endothelial cells – cells that line the blood vessels. While some hemangiosarcoma’s can be successfully treated if they are diagnosed early enough, the challenge is finding the tumor in the first place; it is a covert form of cancer that often goes undetected and results in very non-specific symptoms. Often dogs, like in Rusty’s case, won’t present to the vets until a major event has occurred such as the tumor rupturing inside the abdomen. Learn more with our article “Hemangiosarcoma in Dogs: A Vet Explains Everything You Need to Know“

What is the survival rate of hemangiosarcoma?

Knowledge of average survival rates will aid your decision in knowing when it may be time to euthanize a dog with hemangiosarcoma. The survival rate and life expectancy for a dog with hemangiosarcoma depend on the type of HSA, how soon it is diagnosed and what organs It is affecting. However, due to the aggressive nature of this form of cancer, the survival rate is measured in months rather than years:

• Dermal Hemangiosarcoma: HSA affecting the skin has the best prognosis provided the cancerous tissue is removed before it has a chance to spread. Dermal HSA is associated with sunlight exposure; always have red growths on the skin tested by your local vet. Dermal HSA was shown to have a median survival time of 780 days in one study, however in cases where the cancer invades the underlying subcutaneous tissue the survival time is dramatically reduced.

• Subcutaneous Hemangiosarcoma: Found under the skin, this type of HSA will appear as a dark red coloured growth. This is a more aggressive form of hemangiosarcoma and will spread to the internal organs in almost two thirds of cases. The median survival time for this form of HSA is 172-307 days.

• Visceral Hemangiosarcoma: The most aggressive form of HSA is the visceral form; it carries a poor prognosis and complete surgical removal is challenging. Once hemangiosarcoma spreads to the internal organs the median survival rate is 3-6 months with only 10% of dogs reaching one year of age, even with surgery and chemotherapy. However, once diagnosis takes place most dogs are well into this 3–6-month period already.

Unfortunately, treatment is very rarely curative unless caught very early in the dermal or subcutaneous form.

Can treatment options help?

Because many forms of hemangiosarcoma remain undetected until the advanced stages many forms of treatment have little to no effect. However, if detected early enough, treatment can add months onto an affected dog’s survival time.

Surgery: Surgery is the primary treatment and involves removing as much of the tumor as possible. This will depend on the location of the tumor and if it has metastasized (spread). Surgical treatment may be curative for the dermal form of HSA, but even then dogs affected are at higher chance of more tumors appearing on the body elsewhere. A wide margin of tissue should be removed surrounding the tumor and you should avoid exposing your dog to direct sunlight if possible. Removal of the visceral form of HSA is inherently difficult and doesn’t come without risks such a hemorrhage, but if the tumor can be sufficiently removed then surgery has the greatest chance of increasing survival time. Treating splenic HSA by performing a splenectomy alone (removal of the spleen) gives dogs a median survival time of 1.6 months according to this study.

Chemotherapy: Chemo is often used as adjunctive therapy to surgery, especially if complete removal of the tumor could not be achieved. Various drug protocols are used and although not curative, chemo aims to slow the progression of growth of hemangiosarcoma. Dogs treated with both surgery and chemotherapy have a median survival time closer to 6 months.

Radiotherapy: Usually used as a palliative treatment option, radiotherapy is most often used in cases of the dermal form of HSA where complete surgical removal was not possible. It has limited use in cases of visceral HSA other than reducing pain associated with the disease.

How does surgery and/or chemotherapy improve survival rates?

Surgical treatment and chemotherapy have poor success rates and will only add months to a dog affected with HSA’s lifespan. According to the whole dog journal, the 12-month survival rate is only 6-13% of those dogs treated surgically and 12-20% treated with surgery and chemotherapy. While some dogs may continue to lead a fairly happy and normal life, this time is usually short-lived, and they can deteriorate quickly. Unfortunately, eventually, all dogs with HSA will die of sudden internal hemorrhage.

Dogs that aren’t treated have dramatically reduced survival times. Dogs with the subcutaneous form of disease on average have 6 months to live whereas untreated dogs with the visceral form often die within 2 weeks if they are in late stage.

Important questions to help you decide if you should euthanize a dog with Hemangiosarcoma

1. What stage of disease is your dog at?

Determining what stage your dog is at can be challenging as symptoms are generally non-specific and don’t appear until later in the disease process.

Dog in the early stages may appear more lethargic, have exercise intolerance, and have a reduced appetite.

As the underlying disease progresses, dogs might show symptoms such as vomiting, diarrhea, pale gums, or a distended abdomen.

Dogs in a late stage of the disease may have difficulty breathing, display unusual neurological activity, seizure or suddenly collapse. If your dog is in this situation then it is considered an emergency as they are likely dying of hemangiosarcoma; euthanasia is often the most humane option at this point.

2. How is your dog’s quality of life?

Making the decision to put your dog to sleep is never easy and will depend on what form of hemangiosarcoma your dog has, how quickly it is progressing, how effective treatment will be and their current quality of life. While some treatment options might extend your dog’s lifespan by months to a year, the time will inevitably come when the disease has progressed to a point that it is seriously affecting your dog’s life.

Ultimately your dog’s quality of life is the only thing that matters when making the decision. Ask yourself these questions:

• Does your dog seem happy? Do they still show excitement to do their favourite things?
• Does your dog still have a good appetite?
• Does your dog need assistance moving around?
• Does your dog seem in pain?
• Does your dog regularly vomit?
• Do they have difficulty breathing or regularly gasp for breath?

You can use these criteria to help you decide when to euthanize a dog with hemangiosarcoma; if the answer to most of these questions is a negative one then it is the right time to consider euthanasia – discuss your dog’s case with your vet who can help you make the decision.

If your dog has suddenly collapsed, has pale gums and is gasping for air then it is likely that the hemangiosarcoma has ruptured internally. Depending on the extent of internal hemorrhage and how invasive the tumor is, it might be the right decision to have your dog euthanized there and then before they deteriorate further. There are times when it may be inhumane to put a dog through extensive treatment or surgery if the chances of survival are minimal; it only prolongs the inevitable.

Steps you can take to help you decide when to euthanize a dog with Hemangiosarcoma

Hearing that your beloved companion has a form of cancer with limited treatment options and poor survival rates is devastating news for an owner. Emotions are high and the thought of your dog suffering is a hard reality to face.

Although it is hard to be rational in these situations, you must put the welfare of your dog first – making the decision as to when to euthanize cannot be a selfish one. The ability to perform euthanasia is a blessing; it allows vets and owners to bring an end to an animals’ suffering and allows them to pass with dignity, so take solace in that fact.

To help you come to the right decision, follow these steps:

1. Talk to your vet – Questions to Ask Your Vet to help with Decision on When to Euthanize:
   • What type of hemangiosarcoma does my dog have and what stage are they in?
   • What treatment options are available?
   • What is their survival rate with and without treatment?
   • What symptoms should I look out for that might mean my dog needs euthanizing?
   • Is my dog in pain?
     
2. Take our quiz to help you evaluate your dog’s quality of life: “It is time to euthanize” quiz.
   
3. Learn about the process. If you have concluded that euthanasia is the best thing for your dog, ask you vet what the process entails. Most veterinary clinics will allow the owner to be with their dog at the time of passing and some may even be able to arrange a home visit to allow your dog to be as comfortable as possible. Being prepared for what the euthanizing process involves will prevent any shocks or anxiety leading up to the event; that way you can concentrate on being there for your canine friend.

View our page on Putting an Old Dog To Sleep to learn more.