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Eleven Possible Warning Signs of Cancer

It is sad to say, but cancer is one of the leading causes of death in our older dogs and cats, partly because of owners increased awareness about their quality of care. It is estimated that 50% of dogs over the age of 10 will develop cancer at some point in their remaining years. Early detection of cancer plays a significant role in effective treatment. There are 11 warning signs of cancer. (These signs are very similar in humans.) If your pet develops any of these signs, please don’t ignore them!  Have your pet examined by your veterinarian where it can be accessed further and diagnostics can be performed to aid in the determination of the disease process. Additionally, your veterinarian may refer you to a veterinary oncologist to confirm the diagnosis.

Super Sad Dog with Cancer

So how is a lump identified and named? No growth can be definitively diagnosed without histopathology (a microscopic evaluation of the growth at the cellular level). This can be accomplished via several means:

Chronic Weight Loss

Dog Lung Cancer Radiograph

Tongue Tumor

Cat squamous cell carcinoma

  1. Swollen Lymph Nodes - Lymph nodes are located throughout the body and may enlarge during an infection or when drainage is impeded. The most commonly palpable lymph nodes are those behind the knee (popliteal) or those located behind the jaw (submandibular). When lymph nodes enlarge, it can be an indication of a localized or a systemic process going on, (particularly if multiple lymph nodes are enlarged at the same time). When multiple nodes are enlarged, a biopsy is taken to aid in the diagnosis. An example of a type of cancer that might cause enlarged lymph nodes is Lymphoma.
  2. An Enlarging or Changing Lump - When a lump is noticed by an owner and brought to the attention of their veterinarian, it is documented in the patient’s record including: its size, location, texture as well as its duration. Should any of these things change in a short period of time, the mass should be  aspirated or biopsied or removed for further diagnosis.
  3. Chronic Weight Loss of Unknown Origin - If your pet has not been placed on a diet and it begins to lose a large amount of weight, it is an indication that something is wrong. Remember cancer cells multiply out of control and consume the bodies nutrients (particularly carbohydrates), for their use. As a result cancer patients can look malnourished over a period of time.
  4. Lameness - An unexplained painful, warm swelling on a bony surface of the body is a cause for concern. Such swellings can cause lameness or fractures to the involved bones. Radiographs can be taken of the suspected bones to determine if the swelling is due to a bony type of cancer (ex: Osteosarcoma, Chondrosarcoma, Fibrosarcoma).
  5. Coughing or Difficulty Breathing - Not only can a nonproductive cough be a sign of heart or lung disease, but it can be a common sign of cancer. Chest radiographs are recommended to confirm a diagnosis.
  6. Abdominal Distension - There are many causes of abdominal distension. When an owner notices a sudden enlargement of their pet’s abdomen, this could be an indication that a tumor is growing inside. Radiographs, abdominal ultrasound and endoscopy are useful aids in determining the cause.
  7. Chronic Vomiting and Diarrhea - Any time a pet experiences unexplained vomiting and or diarrhea, further evaluation is indicated. Radiographs, abdominal ultrasound and endoscopy are often useful aids in determining the cause.
  8. Abnormal Mouth Odor - Often owners complain about their pet’s bad breath. It could be an indication that the animal needs a dental. However, foul mouth odor can also be an indication of oral tumors. Owners may notice their pet salivating more with blood in it. They also may not be eating as well. If your pet experiences any of these signs, it should be seen by your veterinarian. There your pet will be further examined after sedation. Radiographs may aid in the diagnosis. The nose and the anal region are additional areas that need to be watched for abnormal foul odors.
  9. Unexplained Bleeding - Often owners confuse constipation for stranguria. Pets with urinary tract infections can strain to urinate and blood may be visible. If a urinary tract infection doesn’t resolve after an extended course of antibiotics, further diagnostics are warranted to rule out cancer.
  10. Straining to Urinate - Often owners confuse constipation for stranguria. Pets with urinary tract infections can strain to urinate and blood may be visible. If a urinary tract infection doesn’t resolve after an extended course of antibiotics, further diagnostics are warranted to rule out cancer.
  11. Nonhealing Wounds - Lacerations or sores that do not heal in a normal time should be further examined for infection, skin disease or even cancer.

While a diagnosis of cancer is certainly scary, it doesn’t mean that you should give up on your pet. There are many types of treatment available including: surgery, chemotherapeutic drugs, radiation therapy and even in some cancers, vaccine therapy.