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What are the signs a dog may be dying of cancer?

If your dog has been diagnosed with cancer and the disease has progressed to the terminal stage, you may see notable symptoms. In this post, our Morton vets discuss common types of cancer in dogs, signs that your dog may be dying of cancer, factors that influence prognosis, and more.

What are the most common types of fatal cancer in dogs?

While you may not realize it, the types of cancers that dogs can get are much the same as the ones that humans experience. These are some common types of cancer we find in dogs:

  • Melanoma: Skin tumors are often found in the feet and mouth of dogs. While melanoma tumors are frequently benign and easily treated, if malignant melanomas are found, they are a serious condition. Sadly, malignant melanoma is prone to spreading quickly to other areas of the dog's body. 
  • Mast Cell Tumor: These tumors can also be found on the skin and may be difficult to remove, depending on the location. However, this type of cancer can be cured - if the tumor is detected early and fully removed. 
  • Osteosarcoma (Bone Cancer): This is most common type of bone cancer found in dogs, and can affect any breed, though larger breeds tend to be impacted more often. 
  • Hemangiosarcoma - Your dog will require emergency intervention for this form of cancer, which can quickly be fatal. Hemangiosarcoma is most often found in blood vessels and on internal organs, though it may occasionally be found on the skin. These tumors may grow to be quite large, with bleeding into the pericardium. 
  • Fibrosarcoma: This slow-spreading form of cancer in dogs can be tricky to treat. In order to prevent a recurrence, radiation and amputation may be necessary.

Breast cancer is another potentially fatal form of cancer in dogs.. By having your female dog spayed, you greatly reduce her risk of developing this internal condition.

What are the stages of cancer in dogs?

Cancer in dogs is broken down into three stages: T, N, and M. According to the Animal Cancer Research Center, the TNM system is based on the extent of the tumor (T), the extent of spread to the lymph nodes (N), and the presence of distant metastasis (M). A number between one and four is then added to each letter to indicate the size or extent of the primary tumor and the extent to which the cancer has spread. 

So, in a T1, they've found a tumor, but it's quite small, and the cancerous cells haven't spread. An M1, however, means that distant metastasis is present (the cancerous cells have been found in other areas of the body).

Other terms your veterinarian may use to describe your pet’s stage of disease include:

  • Local or localized disease: Cancer is confined to one organ or structure.
  • Locally advanced or loco-regional disease: Cancer is metastatic to a local lymph node and/or is locally invasive within the surrounding tissues.
  • Distant or advanced: Cancer has metastasized beyond the local lymph node.

What are the signs of cancer in dogs?

It can be very difficult to tell that something is wrong with your dog just by looking at them. While some types of cancer are only diagnosed using diagnostic testing such as bloodwork, there are certain symptoms that you can watch for that may indicate cancer.

If your dog is showing any of these signs, you'll want to make an appointment with a veterinarian as soon as possible. When it comes to cancer, early detection is key to positive treatment outcomes. If you already know your dog is dying from cancer, you may have seen the symptoms listed below:

  • Sores that don't heal
  • Lumps or bumps beneath the skin
  • Loss of appetite
  • Unexplained weight loss
  • Lethargy, depression, disinterest in exercise
  • Straining when going to the bathroom
  • Strong odor
  • Challenges when eating or swallowing
  • Swelling
  • Pain or difficulty walking, lameness or stiffness

Diagnosing Cancer in Dogs

Your veterinarian will begin by taking a detailed medical history of your pet, then performing a thorough physical examination. If your veterinarian feels that your pet likely has cancer, diagnosis will move to the next level. 

Several tests may be recommended to help determine the extent of the cancer such as urinalysis, ultrasound, digital X-rays, biopsy, blood tests (blood count, chemistry profile) and tissue aspirates. Other diagnostic tests that may also be recommended include CT, PET or MRI scans, lymph node aspirated, endoscopy, bone marrow aspirate and/or immunologic studies. 

Once your veterinarian receives the results of the diagnostic tests they will be better able to understand the nature of the disease in your pet and determine the best treatment options to meet your pet's needs. If your pet needs more specialized treatment, our vets in Morton will refer you to a veterinary oncologist.

Managing & Treatment for Cancer in Dogs

As with cancer in humans, the cancers that affect the health of your dog will vary in how quickly they grow and spread and how easily they can be treated. The earlier treatment begins the better the prognosis for your pet. 

The treatment for your pet's cancer will depend upon a number of factors but may include immunotherapy, chemotherapy, radiation therapy, targeted therapy, surgery and/or palliative care is your dog is dying.

Prognosis & Timelines For Pets With Cancer

Tumors with the best chance of being treated or cured are those that have not invaded surrounding tissues. 

However, if the tumor has spread to other organs, it is typically incurable.

While some cancers can be treated very successfully, other more aggressive cancers, such as bone cancer, can move alarmingly fast once symptoms have been detected. Once your pet has been diagnosed your vet will review your pet's prognosis and provide you with treatment options and potential outcomes.

Palliation, often referred to as "palliative care", may help to relieve symptoms and potentially prolong life without providing a cure. Often a veterinarian will prescribe medications such as pain relievers to help keep your dog comfortable as it's dying.

Only your veterinarian will be able to provide you with a prognosis and timeline for your pet, and even then, they're giving it their best guess.

Should you euthanize a dog that has cancer? 

If your dog has been diagnosed with a fatal form of cancer, and is already not doing well, it might be time to discuss euthanization with your veterinarian.

Think about what's best for your dog. If your dog is already old, and isn't doing well, and is now dying of cancer, it might be time to say goodbye if they are miserable. It is extremely important to have this conversation with your veterinarian and decide what is best for your specific situation. 

Veterinary Internal Medicine at Stoney Creek Veterinary Hospital

Our vets in Morton understand you may be feeling many emotions about your dog’s diagnosis and cancer journey.

We are here to address your questions and concerns, explain any treatment/management options in plain language and help you navigate this difficult time. Our hospital is committed to comprehensive care for pets, partnering with veterinary specialists near Morton, including specialized oncologists. If your pet needs something beyond our expertise, we will refer you to one of them.

Note: The advice provided in this post is intended for informational purposes and does not constitute medical advice regarding pets. For an accurate diagnosis of your pet's condition, please make an appointment with your vet.

Has your dog been diagnosed with a serious internal medical condition? Our Morton vets can provide disease management and treatment options. Contact us today.

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Stoney Creek Veterinary Hospital is accepting new patients! Our experienced vets are passionate about the health of companion animals in Morton and surrounding areas. Get in touch today to book your pet's first appointment.

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