Dog Brain Tumor Progression Timeline

Your dog’s prognosis depends on whether the brain tumor is primary or secondary, and the severity of clinical signs. For a primary brain tumor, survival may be between three to six months with only palliative care, or 5 to 28 months with radiation and/or surgery.

However, these tumors vary widely in their level of malignancy and some can be treated effectively. Unfortunately, there is still a lot that we do not yet know about how different types of brain tumor behave in dogs and cats, and this can make it difficult to advise owners as to the best form of treatment for their pet. This web page provides information on what we do know about the diagnosis, treatment and prognosis of different types of brain tumor and describes ongoing research efforts at North Carolina State University College of Veterinary Medicine.

The aim of surgical removal of a brain tumor is either to cure the disease by complete removal (which only occurs rarely) or to alleviate the clinical signs by decompressing the brain. This can be life saving if the mass is very large. Brain tumors can be removed surgically if they are located in a site that can be reached safely. There are two considerations for this, firstly, how close is the tumor to the surface of the brain and secondly, how close is the tumor to critical areas of the brain. Tumors of the brainstem pose problems on both of these fronts. They are difficult to access because of the thick bone surrounding them, their location close to the floor of the cranial cavity, and because the brainstem does not have much redundancy of function so damaging it could be fatal. In contrast, there is much more functional redundancy in the forebrain: you can resect certain parts of the forebrain without long-term effects. Meningiomas tend to be located on the surface of the brain and are therefore the best candidates for surgical removal. Gliomas are more difficult to remove because they lie deep within the substance of the brain.

If you either suspect your dog has a brain tumor, or it has already been diagnosed with a brain tumor and you would like to come to the NC State Veterinary Hospital for further evaluation or treatment by the neurology service, please ask your veterinarian to contact the neurology service at 919.513.6692 to make a referral.

If none of the above therapies are an option, it is possible to treat the signs caused by a brain tumor. For example, any dog with a brain tumor that has seizures will be placed on an anti-epileptic drug such as Phenobarbital. Tumors tend to cause the accumulation of fluid (edema) around them and this can be treated with a corticosteroid such as prednisone. As many of the clinical signs can be due to the edema, some animals show a dramatic improvement within 24 hours of starting treatment with prednisone. This response is often short lived as the tumor itself is not being treated by this drug, but can certainly give owners and pets some good quality time.

Meningioma – This is the most common primary brain tumor in dogs and cats (and in humans). It arises from the arachnoid mater of the meninges (the membranes that line the brain) rather than the cells of the brain itself. As such, meningiomas are not strictly brain tumors, but tend to be grouped with them because they arise within the cranial cavity and compress or invade the brain. Figure 3 is a MRI of a meningioma. These tumors occur more commonly in long nosed (doliochocephalic) breeds of dog, such as the Golden retriever. Meningiomas are usually relatively slow growing and amenable to treatment, although more malignant forms do occur.

Can brain tumours be treated?

Advances in veterinary care for pets mean that brain tumours in dogs and cats can be treated, although unfortunately there are few tumours which can be cured. Treatment is usually aimed at providing your pet with the best possible quality of life for as long as possible. Whatever treatment course you decide upon, if your dog or cat is having seizures they should be given medication to control these – as the seizures are likely to be permanent.

Are There Different Types of Brain Tumor?

Types of brain tumours are either primary or secondary. The primary tumour is where the cancer originated within the brain cells and membranes.

The most common of these primary tumours include:

  • Adenocarcinoma
  • Choroid plexus papilloma
  • Glioma tumour
  • Meningiomas
  • Pituitary adenoma
  • Secondary brain tumours originate from cancer cells in other part of the body – spreading to the brain through metastasis. Or developing from a nearby non-nervous system tissue which spreads into the brain tissue such as cancer of the nasal cavity. When secondary brain tumours are diagnosed the cancer has spread throughout the body. Secondary brain tumours include hemangiosarcoma, mammary carcinoma and melanoma.


    What are the final stages of brain tumor in dogs?

    There can be a wide variety of additional signs such as difficulty swallowing, change in voice and inability to move the eyes. Further progression of the signs can result in paralysis, coma and death.

    How long does a dog have to live with a brain tumor?

    The prognosis for brain tumours in dogs is poor, with a median (average) survival time of around two months with supportive care alone. However, with treatment, the vast majority of dogs can be significantly helped. Knowledge on the prognosis is limited.

    How does a dog act with a brain tumor?

    Other signs commonly seen are blindness, changes in the animal’s personality, profound lethargy, circling and disorientation. Some people may notice that their pet appears to have a ‘headache’. As with seizures, some of these signs may be permanent whatever the treatment course that you decide upon.

    Are dogs in pain with brain tumors?

    Depending on the stage of cancer, your pet may be in a lot of pain. It will likely be prescribed anti-inflammatory drugs and opioids to relieve pain throughout treatment. The good news is that treatment options are available.