Hearing the words “I’m sorry, it’s cancer” is something no pet parent ever wants to experience. Our pets are family, and the thought of them facing illness or pain can be devastating. Unfortunately, cancer is a reality for many animals, with rates in dogs comparable to those in humans, and around one in three cats affected during their lifetime.
While these statistics can sound daunting, understanding the warning signs, common types, and how to reduce risk can help you take proactive steps to protect your furry friend.
Common Cancers in Dogs
Cancer can affect any organ or tissue in a dog’s body, but a few types appear more frequently:
Mast Cell Tumours (MCTs)
A form of skin cancer often appearing as lumps, though it can affect internal organs. Middle-aged to older breeds like Boxers, Pugs, and Golden Retrievers are most at risk. MCTs vary in severity, so any new lump should always be checked by a vet.
Melanoma
Like in humans, melanomas appear as dark or pink spots, commonly in the mouth, nail beds, or on the skin. They’re most often seen in dogs over 10 years old. Early detection is vital, as oral melanomas can be aggressive.
Lymphoma
A cancer of the white blood cells, lymphoma affects organs such as the lymph nodes, liver, and spleen. Symptoms vary depending on where it occurs but can include swollen lymph nodes, vomiting, diarrhoea, or weight loss.
Osteosarcoma (Bone Cancer)
A painful cancer typically affecting large and giant breeds such as Great Danes, Rottweilers, and Irish Wolfhounds. Look out for swelling, limping, or changes in appetite and activity.
Hemangiosarcoma
An aggressive cancer that develops in blood vessels, often affecting the spleen, heart, or skin. It’s more common in Golden Retrievers, Labradors, and German Shepherds. Warning signs include lethargy, weight loss, or pale gums.
Common Cancers in Cats
Cats can also be affected by several types of cancer, particularly as they live longer, healthier lives.
Lymphoma
The most common feline cancer, affecting lymph tissue in organs such as the liver, kidneys, and intestines. Cats with a history of Feline Leukemia Virus (FeLV) infection are especially at risk. Symptoms include weight loss, swelling, or difficulty swallowing.
Squamous Cell Carcinoma (SCC)
Often caused by sun exposure, SCC appears on the nose, ears, or eyelids, especially in white or light-coated cats. It may look like a sore or scab that doesn’t heal.
Fibrosarcoma
A tumour of the soft tissue that appears as a firm lump under the skin. These cancers are often slow-growing but can invade surrounding tissue.
Mammary (Breast) Cancer
Unspayed female cats are far more prone to mammary cancer, which starts as a small lump near a nipple. Siamese cats are particularly susceptible.
What Causes Cancer in Pets?
Just like in humans, the causes are complex but several known factors can increase risk:
Sun exposure: Linked to skin cancers in both cats and dogs.
Tobacco smoke: Second-hand smoke significantly increases cancer risk in pets.
Chemicals: Exposure to pesticides, herbicides, and pollutants can play a role.
Hormones: Unspayed females have a much higher chance of developing mammary cancer.
Treatment Options
Treatment depends on the type, stage, and location of cancer. Surgery is often the first step to remove a tumour, followed by chemotherapy or radiation to destroy remaining cells.
Unlike humans, most dogs and cats tolerate chemotherapy well, they usually don’t lose their fur or experience severe side effects.
Emerging treatments such as immunotherapy (using vaccines to trigger the immune system) and stem cell therapy are also offering new hope for many pets.
Reducing Your Pet’s Risk
While genetics can’t be changed, lifestyle choices make a big difference:
Spay or neuter early: This dramatically reduces mammary and testicular cancers.
Feed a balanced diet: Quality nutrition strengthens immunity and overall health.
Avoid toxins: Keep pets away from cigarette smoke, garden chemicals, and air pollution.
Limit sun exposure: Especially for light-skinned pets.
Schedule regular vet checks: Early detection saves lives.
A Final Word of Hope
A cancer diagnosis no longer means the end for our pets. Advances in veterinary medicine are improving outcomes every year, and many dogs and cats go on to live happy, comfortable lives for years after treatment.
If your pet is diagnosed, speak with your vet about all available options and remember, love, comfort, and early care can make all the difference.
