Signs of Cancer in Your Pets

According to The Veterinary Cancer Society, cancer is the leading cause of death in 47% of dogs, especially over the age of 10, and in 32% of cats. Approximately 1 in 4 dogs will develop neoplasia (abnormal growth of tissue) in their lifetime. There are nearly 100 types of pet cancers and while getting a cancer diagnosis can be devastating for a pet owner, dogs and cats today have a better chance of being successfully treated than ever before.

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Early recognition and diagnosis are crucial, so be aware of changes in behavior as well as sudden physical changes that could signal your pet has cancer. These are the most common warning signs of cancer in dogs and cats:

1. Sudden, Changing Lump: As one of the most well-known signs of cancer in humans, the same is applicable to animals. A lump can be an indicator of many kinds of cancer (skin cancer is the most common in pets) and it should be biopsied as soon as possible to determine whether it’s benign or malignant.
2. Abdominal Distention: When the stomach area becomes rapidly enlarged, this may suggest a mass or tumor in the abdomen, or it may indicate bleeding that is occurring in this area. A radiograph or ultrasound of the abdomen can be very useful since abdominal tumors are the second most common in pets.
3. Swollen Lymph Nodes: Dogs’ and cats’ lymph nodes can be found throughout the body, but are most easily detected behind the jaw or knees. When swollen, this can be a sign of lymphoma, another common cancer in pets.
4. Lameness: Unexplained and sudden changes in stance and gait can be an indicator of bone cancer. Large and giant breed dogs older than 7 are most prone to bone cancer, while cats are rarely diagnosed with this type of cancer.
5. Oral Odor/Bleeding Gums: Periodontal disease is common in pets and, if not addressed early and continuously, can lead to neoplasias in the mouth and neck. If you notice changes in appetite, chewing, food type preference (hard vs soft food), and gum color, take your pet to your veterinarian immediately. Head and neck neoplasias tend to be malignant and aggressive.
6. Mammary Gland Masses: Benign and malignant tumors of the mammary glands are the most common type of tumor diagnosed in unspayed female dogs. Other signs of breast cancer in pets include superficial loss of tissue on the surface of the skin over the mammary tissue, frequently with inflammation and/or drainage, and swelling of nearby lymph nodes.
7. Persistent Sores: Wounds that never quite heal and continue to bleed/discharge despite time, antibiotics, or ointments can be an indicator of multiple types of cancers. Have a veterinarian check your pet if you’re concerned about their sores.
8. Persistent Cough: A dry, non-productive cough in older dogs could indicate a tumor near the lungs or heart. Keep in mind that younger dogs who have been recently adopted or boarded are more likely to be suffering from kennel cough than cancer.
9. Difficulty Urinating/Defecating: While straining to pee is often an indicator of a urinary tract infection, there may be cause for concern if the UTIs are recurrent or bloody. Difficulty pooping and a sustained foul odor could also indicate a mass in or around the anal area.
10. Unusual Signs or Behaviors: Additional ailments and behaviors that could be indicators of cancer include sudden weight gain/loss, chronic vomiting and/or diarrhea, unexplained bleeding, difficulty breathing or swallowing, and sudden loss of stamina or energy.

When cancer is either suspected or confirmed, your veterinarian will recommend that you consult with a veterinary oncologist. Together, your veterinarian and veterinary oncologist will determine the best course of action and provide the best care for your pet.