Perhaps the most horrifying news that any pet owner can receive is that their beloved four-legged companion has a brain tumor. As individuals with a plethora of information at the tips of our fingers, we know all too well just how destructive brain tumors can be. Knowing that our furry companion is going through such pain can be impossibly hard and leave pet parents not knowing how to proceed.
We wish more than anything that we had a magical solution to eliminate your dog's pain and reverse the heart-wrenching diagnosis. In time, with future advancements in science, we hope that this can one day be a reality. Until then, we hope to be able to inform our readers about everything they need to know about brain tumors in dogs. We truly believe that the more you know, the better equipped you will be for handling any situation that comes your way.
Let's start with the basics.
What is a Brain Tumor in Dogs
The term tumor refers to any type of abnormal cell growth. Therefore, a brain tumor is an intracranial tumor that originates from the abnormal growth of cells and irregular cellular division within the brain. Brain tumors in dogs are typically found in the brain itself. However, it is also possible for the tumors to develop in the skull, the cranial nerves, the meninges (the brain envelopes), or the pineal and pituitary gland.
Canine brain tumors are diagnosed more often in older dogs. Additionally, studies have found that certain breeds are at increased risk of developing brain tumors. With that being said, it is entirely possible for a dog of any age and any breed to develop a brain tumor.
There are two types of brain tumors, primary and secondary, and treatment will fluctuate depending on which type of tumor is found and how far along the tumor has progressed.
Types of Brain Tumors
When a veterinarian diagnoses a brain tumor they will either diagnose it as primary or secondary. The specification is essential in order to proceed with appropriate treatment of the tumor.
Primary Brain Tumors
A primary tumor is one in which the cancer originated in the brain’s cells and its membranes. Extensive research has found that certain types of primary brain tumors affect specific breeds of dogs more than others. Again, this is another example of how knowledge is power. Being aware of specific ailments that your dog is at a higher risk for is an important first step in prevention and catching the disease early on. The sooner any disease is discovered, the better the prognosis for recovery is.
The most common primary brain tumors include:
- Glioma tumor
- Choroid plexus papilloma
- Pituitary adenoma
Secondary Brain Tumors
Secondary brain tumors differ from primary brain tumors in that they originate from cancer cells in another area of the body. These cancer cells then spread to the brain through a process referred to as metastasis. Additionally, a secondary brain tumor may develop from an adjacent non-nervous system tissue which extends into the brain tissue. For example, cancer of the nasal cavity which extends to the brain.
The most common secondary brain tumors are:
- Mammary carcinoma
Due to the fact that secondary brain tumors are the result of the cancer spreading, by the time that they are finally diagnosed, cancer has spread throughout the body. Therefore, unfortunately, the prognosis for secondary brain tumors is usually not very positive.
Brain Tumor Symptoms
As with all diseases, the sooner it is diagnosed, the greater the chance of effective treatment and recovery. Unfortunately, many early clinical signs of brain tumors appear as what is known as non-specific symptoms. Non-specific symptoms are those which are signs of a multitude of ailments, they are not specific to brain tumors alone. Therefore, it can be challenging for pet owners to pinpoint exactly what is going on. However, brain tumors grow rapidly and aggressively leaving no time to wait it out and see if the symptoms go away.
If you notice any of the following changes in your dog, no matter how small, it is imperative that you see a veterinarian for a check-up. An early diagnosis can ultimately be the difference between life and death for a dog with a brain tumor.
Warning Signs of Brain Tumor
The following is a list of warning signs that are typically associated with a brain tumor in dogs.
- Seizures (seizures are the most common early clinical sign of a brain tumor in dogs)
- Head tilting
- Cranial nerve deficits
- Loss of balance/ “drunken” walk
- Decreased vision or loss of vision
- Difficulty swallowing
- Voice change (being more vocal or hoarseness)
- Overall weakness and lethargy
- Strange behaviors (mood changes and aggression)
- Gain or loss of appetite
- Weight loss
Dogs are notorious for hiding pain and acting like everything is normal. Knowing your dog's typical day-to-day behavior is imperative when it comes to being able to recognize when something isn't right.
Signs of a Brain Tumor in Late Stages
The following are signs of brain tumors that are in late stages. Again, if you notice any of these clinical signs it is paramount that you seek medical intervention immediately.
- A continuation of persistent early-stage symptoms
- Reclusive or solitary behavior
- Walking in circles
- Pressing against a hard surface
- Worsening weakness leading to an inability to stand
- Worsening seizures
Critical Stage Brain Cancer Symptoms
Dogs in critical stages of brain cancer will commonly have the following symptoms:
- Difficulty breathing
- Continued worsening seizures (the seizures will lengthen in time and frequency)
- Uncontrollable diarrhea
- Uncontrollable vomiting
- Sudden collapse
- Excessive bleeding (internal or external or both)
- Crying and whining out of pain*
*Just to reiterate, dogs rarely show that they are in any amount of pain. Therefore, if your dog is crying out in pain, their discomfort has reached an extremely high level.
What Causes Brain Tumors
Even with extensive, consistent research on the topic, the specific cause of brain tumors in dogs and cats is still relatively unknown. With that said, experts do have several hypotheses as to potential causes. These include:
- Environmental toxins
- Dietary factors
- Chemical toxins
- Hereditary predispositions
- Weakened immune system
Studies have discovered links between environmental toxicity and many cancers found in humans. It is pretty safe to assume that if something can cause cancer in people like you and me, it can have the same detrimental result in our four-legged friends. Things like preservatives in our foods and fertilizers in the soil we play in are all being tied to illnesses, including cancers.
Furthermore, many experts believe that over-vaccination can also lead to the development of cancer. This in itself is a topic that has many concerned, confused, and frustrated. We encourage our readers to do their homework before agreeing to the slew of recommended yearly dog vaccinations. If your dog doesn't spend time at kennels, they likely don't need certain shots. If you live in certain parts of the country, you may be able to avoid other vaccines. Know what your dog is receiving and be aware of the potential side effects. Cancer is only one of the dozens of potential adverse reactions that your dog may face from over-vaccination.
Higher Risk Breeds for Brain Cancer
Additionally, certain breeds are at a higher risk of developing brain tumors. These breeds include:
- Golden Retrievers
- Doberman Pinscher
- Scottish Terrier
- Old English Sheepdog
- Boston Terriers
Interestingly enough, experts have even found that certain breeds of dogs are at a higher risk of developing certain types of brain tumors. For instance, brachycephalic breeds (such as Boxers, English Bulldogs, and Boston Terriers) are at higher risk of developing gliomas, or tumors of the interstitial tissue of the central nervous system). Conversely, dolichocephalic breeds of dogs, characterized by long heads and noses such as Collies and Golden Retrievers, are at a higher risk of developing meningiomas, or tumors that develop in the membranes covering the brain.
Again, this is why is it so important to understand the risks that your dog may be genetically predisposed to developing. By staying informed and being aware you have the ability to save your dog's life.
With that said, while certain breeds are at a higher risk, any dog breed may develop a brain tumor. Typically, brain tumors are diagnosed in dogs over the age of five years old, but they can be diagnosed at any age.
Diagnosing a Brain Tumor in Dogs
A brain tumor will often be suspected if your dog does not have a history of neurological issues or a brain condition and has a sudden onset of the aforementioned symptoms.
In order to make an accurate diagnosis, your veterinarian will perform an array of tests, usually beginning with blood work. The blood tests, including a complete blood count, will alert the vet of any abnormalities and signs of infection.
Your veterinarian will also order for x-rays of the chest and abdominal areas. The x-rays and blood work will show whether or not the cancer or additional tumors have spread elsewhere in the body.
Next, your vet will likely perform an MRI (magnetic resonance imaging ) or CT scan (computerized tomography). Due to the fact that soft tissue brain tumors are unable to be seen with an x-ray of the skull, an MRI or CT scan is almost always necessary in order to make an accurate diagnosis.
In most cases, an MRI or CT scan is enough for the vet to be able to determine the type of brain tumor that the dog has. However, a sample of the mass by means of surgery or by taking a surgical biopsy will be necessary in order to make a definite diagnosis. The biopsy will also inform the vet of the malignancy of the brain tumours.
Treating Brain Cancer in Dogs
Treatment for the brain tumor is determined by whether it is a primary or secondary tumor as well as where it is located. Typically, surgical removal, radiation therapy, and occasionally chemotherapy are the most common methods of treatment for both dogs and cats.
When your veterinarian is determining how to treat the tumor, the primary objective (and best case scenario) is total removal of the mass. If total removal is possible, your vet will likely perform surgery as soon as possible. After the surgery is complete, your vet may recommend additional radiation treatments in order to prevent any regrowth of the tumor.
However, in some cases, surgical removal isn't possible. Tumors can develop locations that are inoperable. In these cases, radiation therapy and chemotherapy are used to shrink the tumor as much as possible.
Typically, radiation therapy is the preferred means of treatment over chemotherapy. Chemotherapy drugs have blood-brain barrier limitations that greatly limit the effectiveness of the treatment.
As you may imagine, treatment for the brain tumor doesn't come without its share of side effects. Your veterinarian may prescribe drugs such as anti-seizure medications and medicine to relieve pain, intracranial pressure, and reduce nausea during and after treatment.
During and after treatment it is imperative that dogs with brain tumors have regular health evaluations by their veterinarian. Additional CT scan or MRIs may be necessary in order to confirm that the treatment and recovery plan is going as planned and there aren't any signs of regrowth.
Additionally, as we previously mentioned, seizures in dogs are directly associated with brain tumors. Pet parents will need to closely monitor their dog after treatment and make sure there is not increased seizure activity.
Finally, brain tumors can lead to weakened swallowing reflexes from the increased pressure of cerebrospinal fluid in the skull cavity. The weakened swallowing reflexes can lead to the development of aspiration pneumonia. It is important to be on high alert for any health changes as your dog's immune system is in a fragile state post-treatment.
Prognosis for Dogs with Brain Tumors
The prognosis for dogs with brain tumors is guarded to fair. Ultimately, the prognosis depends greatly on how quickly the cancer was diagnosed and the means of treatment. Therefore, the median survival time can vary.
Approximate survival time is as follows:
- 2-4 months with supportive care alone
- 6-12 months with surgery alone
- 7-24 months with radiation therapy alone
- 6 months to 3 years with surgery combined with radiation therapy
- 7-11 months with chemotherapy alone
Again, all dogs are different are all will react differently to the treatment.
Preventing Brain Tumors
Of course, as a pet parent, you are likely wondering how to prevent your pup from experiencing the horrific disease. Unfortunately, due to the fact that the definite cause of brain tumors is still unknown, there are not specific means of prevention. With that being said, many studies are continuing to link toxins to various forms of cancers. Toxins are legitimately found everywhere and there's no real way to completely eliminate them. However, by limiting vaccinations, proving your dog with a species appropriate, nutritionally balanced diet, and avoiding environmental toxins such as pesticides, you can help prevent the development of a slew of ailments, including cancer.
CBD for Dogs
Many pet owners make it a priority to stay up to date on the latest and greatest advancements in holistic wellness. If you're one of these individuals, you've likely heard of CBD.
CBD oil is supplement derived from the hemp plant.
Brain Tumor in Dogs: A Closing Thought
Your pets mean the world to you. Trust us, as dog owners, we completely understand the enormous amount of love that you have for your fur children. There is no right thing to say that can reverse a brain tumor diagnosis. However, there is hope and ways to ensure that you are doing all you can to prevent the disease from developing.
Again, knowledge is power. It is so important to know all there is to know about your dog's individual breed. If your dog is at a higher risk of developing a brain tumor, it is imperative to be aware of the early signs so that you are able to act in a timely and appropriate manner.
Finally, understand your dog's "normal." All dogs are different. Some are born couch potatoes while others are constantly full of energy. Some are picky eaters while others will devour anything in site. By knowing your dog's normal behavior you'll be able to quickly identify when something is off. If and when this occurs, act straight away. Don't delay hoping that Fido will soon return to their "normal." A timely diagnosis for any disease, particularly a brain tumor, can truly make a world of difference for your beloved furry companion.