10 Warning Signs That Your Dog May Have Cancer

There are some alarming statistics on Cancer in Dogs. According to recent stats from VPI Pet Insurance, dogs are:

  • Twice as likely to develop leukemia than humans
  • Four times more likely to suffer from breast cancer.
  • Eight times more likely to develop bone cancer.
  • An incredible thirty-five times more at risk for developing skin cancer.

So, the question is, WHY is cancer in dogs so prevalent? The answer likely is the amount of exposure our pets receive to carcinogens in their environment.

They may actually be consuming carcinogens in their dog food. According to http://www.vettech.org/10-dog-foods-that-may-lead-to-cancer, some of the chemicals used to preserve pet foods have been revealed to be cancer causing agents. Sadly, mouth cancer is actually the fourth leading cause of cancer deaths in dogs.

Dogs regularly inhale unseen cancer causing materials. When does a dog ever really stop sniffing everything it comes in contact with? Carcinogens in the environment tend to settle on the ground and other objects, where they remain in trace form until Fido sniffs them up. These carcinogens may have a cumulative effect and eventually cause one or more types of cancer to develop.

Dogs get a lot of sun exposure. This is one that Chihuahua owners should especially watch out for. If you have a Chihuahua, then you know how much they LOVE to soak up the sun. Mine would do it all day if I let them. Of course, sunshine and fresh air are both good for dogs, but how many of us consider sun protection for our pets. Yes, responsible owners provide shade for their pets to escape the sun, but on mild days, a dog is just as likely to bask in the sunlight for hours. This can result in a phenomenal amount of ultraviolet exposure and is likely the culprit responsible for so many incidences of skin cancer in dogs.

According to Colorado State University, as many as 50% of pets die of cancer, making it a leading cause of pet death. All of these statistics are horrible but my intention in posting this is not to scare you, but to make you aware. So, knowing this and knowing that treatments are insanely expensive, what can you do? The above website lists dog food ingredients to look for and avoid. We can also watch for the following warning signs and try to catch it early should it happen to our beloved pet (s).picture of a fawn and white chihuahua that looks sad, may have cancer

Ten warning signs of Pet Cancer

  1. Swollen Lymph Nodes
  2. An Enlarging or Changing Lump
  3. Abdominal Distension
  4. Chronic Weight Loss
  5. Chronic Vomiting or Diarrhea
  6. Unexplained Bleeding
  7. Cough
  8. Lameness
  9. Straining to Urinate
  10. Oral Odor

Swollen Lymph Nodes

These “glands” are located throughout the body but are most easily detected behind the jaw or behind the knee. When these lymph nodes are enlarged they can suggest a common form of cancer called lymphoma. A biopsy or cytology of these enlarged lymph nodes can aid in the diagnosis.

An Enlarging or Changing Lump

Any lump on a pet that is rapidly growing or changing in texture or shape should have a biopsy. Lumps belong in biopsy jars, not on pets.

Abdominal Distension

When the “stomach” or belly becomes rapidly enlarged, this may suggest a mass or tumor in the abdomen or it may indicate some bleeding that is occurring in this area. A radiograph or an ultrasound of the abdomen can be very useful.

Chronic Weight Loss

When a pet is losing weight and you have not put your pet on a diet, you should have your pet checked. This sign is not diagnostic for cancer, but can indicate that something is wrong. Many cancer patients have weight loss.

Chronic Vomiting or Diarrhea

Unexplained vomiting or diarrhea should prompt further investigation. Often tumors of the gastrointestinal tract can cause chronic vomiting and/or diarrhea. Radiographs, ultrasound examinations and endoscopy are useful diagnostic tools when this occurs.

Unexplained Bleeding

Bleeding from the mouth, nose, penis, vagina or gums that is not due to trauma should be examined. Although bleeding disorders do occur in pets, they usually are discovered while pets are young. If unexplained bleeding starts when a pet is old, a thorough search should be undertaken.


A dry, non-productive cough in an older pet should prompt chest radiographs to be taken. This type of a cough is the most common sign of lung cancer. Please remember there are many causes of a cough in dogs and cats.


Unexplained lameness, especially in large or giant breed dogs, is a very common sign of bone cancer. Radiographs of the affected area are useful for detecting cancer of the bone.

Straining to Urinate

Straining to urinate and blood in the urine usually indicate a common urinary tract infection; if the straining and bleeding are not rapidly controlled with antibiotics or are recurrent, cancer of the bladder may be the underlying cause. Cystoscopy or other techniques that allow a veterinarian to take a biopsy of the bladder are useful and sometimes necessary to establish a definitive diagnosis in these cases.

Oral Odor

Oral tumors do occur in pets and can cause a pet to change its food preference (i.e. from hard to soft foods) or cause a pet to change the manner in which it chews its food. Many times a foul odor can be detected in pets with oral tumors. A thorough oral examination with radiographs or CT scan, necessitating sedation, is often necessary to determine the cause of the problem.

Cancer treatment for pets is so expensive, few can afford it. The following website is a great resource that can help those who cannot aford the high cost of treatment. You can also donate if you would like to help others who face this unimaginable hardship and pain.


After researching this subject and reading all the alarming statistics, I can not imagine being faced with having a pet with cancer that could be cured and not having the money to help my pet to live a longer life. There are resources out there that can help.

The following website contributes to pet cancer research, so ChiChis And Me made a donation today and I hope that in some small way it helps.










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