Dealing with Dog Cancer

Is Canine Cancer a Death Sentence?

The leading cause of death in dogs over the age of two years is cancer. In dogs 10 years and older the risk of developing cancer increases exponentially, according to a blog post from April 2017 from

Cancer is a scary prospect whenever it is diagnosed in human or pet. If caught early, approximately half of all cases of cancer in dogs are treatable, according to the National Canine Cancer Federation (NCCF).

Whether the disease is first detected by a growth or lesion or when a pet begins showing signs of illness, it is very important to follow the advice of a veterinarian regarding immediate treatment.

One of my pups, at age 12, developed a lesion between his toes that started to grow and bleed. His vet biopsied the growth and found it to be cancer. We had the lesion removed but it returned and began to proliferate on his front leg. Eventually, and with no guarantee the cancer wouldn’t develop elsewhere, we had his leg amputated.

Fortunately, this bought him a few more years and a much better quality of life. But his temporary healing was an emotionally draining roller coaster ride. In hindsight, I should have asked his vet to amputate his foot right after we learned he had cancer.

Because so many canine cancers are treatable in the early stages it’s important to familiarize yourself with the most common forms and just how aggressive they are. 

  • Lymphoma — Considered to be the most common form of cancer in dogs. It is an overgrowth of cells in the bone marrow and lymph nodes, as well as other tissues. It is often found in dogs from six to nine years of age. This form of cancer spreads rapidly and usually is detected by swollen lymph nodes in the neck or swelling behind the knees. Fogs at a lower risk of lymphoma are Dachshunds and Pomeranians.
  • Hemangiosarcoma — Cancer of the blood vessels that often affects the heart, liver or spleen but can spread to other organs. It can also be detected just below the skin and seldom presents symptoms before it has progressed to advanced stages.
  • Mast Cell Tumors — These usually present as lesions on the dog’s skin and cause discomfort. They affect the skin, lungs and intestines and are common in mixed breeds and senior dogs. Mast cells transport enzymes and histamines that protect your dog but when they grow out of control the cells attack a dog’s immune system.
  • Melanoma — A form of skin cancer that is very aggressive and spreads rapidly. Melanoma is often benign and starts on the surface of the skin, however as it progresses it  grows inward and attacks vital organs. It can initially present as drainage from the eye, a swollen paw or pads or a lesion around the mouth. Often times, benign (or non-cancerous) tumors can be removed without the necessity of additional treatment.
  • Osteosarcoma — Bone cancer, which most often occurs in large breed dogs in midlife. Osteosarcoma grows rapidly and is usually malignant (cancerous). It appears most often in legs but can afflict any bone in the body. In its earliest stages symptoms include swelling of the limbs and limping.
  • Mammary Cancer — Malignant tumors that start in the mammary glands of female dogs and are rare in male dogs. This form of cancer is more commonly found in female dogs that are not spayed or were spayed after two years of age. After surgical removal chemotherapy may be recommended. Few cases of canine Mammary Cancer are ever fatal provided the tumors are removed. Poodles, dachshunds and spaniels are most affected.

A dog’s chance of developing cancer increases with age and there are specific breeds more prone to cancer. They are:

  • Rottweiler
  • Bernese Mountain Dog
  • Bouvier des Flanders
  • German Shepherd
  • Great Dane
  • Doberman Pinscher
  • Labrador Retriever
  • Cocker Spaniel
  • Boxer
  • Golden Retriever

Remember, early detection is a lifesaver. Check your pet’s coat and skin regularly for growths and lesions. Always remain vigilant so symptoms of illness don’t go undetected for too long. Even something as subtle as a change in appetite or mood can be an early sign of trouble. You pet’s veterinarian should promptly be consulted about any changes in appearance, appetite, mood or activity!

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