The C-word: what every pet parent should know about cancer in pets

Cancer isn't a word anyone wants to hear about their pet, but it's more common than most of us realise, and knowing what to look for genuinely helps. According to the American Veterinary Medical Association, around one in four dogs will develop cancer at some point in their life. It's not a small number, and it's exactly why understanding the signs matters. So, what are the common types of cancer in dogs? A handful of cancer types account for most diagnoses in dogs: mast cell tumours, lymphoma, sarcoma, carcinoma and osteosarcoma. Each behaves differently and responds differently to treatment, which is part of why an early, accurate diagnosis makes such a difference. Which breeds are most affected? Any dog or cat can develop cancer, but some breeds do carry a higher risk than others. According to 2024 PetSure claims data, lymphoma is one of the costliest conditions affecting dogs, with Bullmastiffs, English Mastiff crosses, Miniature Australian Bulldogs, Curly Coated Retrievers and American Bulldogs among the breeds most represented in claims. For cats, lymph node cancer ranks as the single most expensive condition treated in 2024, most commonly seen in British Shorthairs, Ragdolls and Domestic Shorthairs. So, what are the telltale signs I should look out for? Cancer can show up almost anywhere, and the signs vary depending on where it is and how far it's progressed. Here's what's worth keeping an eye on: Skin: lumps, wounds, ulceration, scabs or swelling. This is one of the best reasons to keep up regular grooming — you'll notice a new lump long before it becomes a problem. Tummy trouble: vomiting, diarrhoea, blood in stool or vomit, constipation. The bigger picture: lethargy, weight loss, changes in appetite, persistent bleeding, breathing changes, a sudden collapse, or swollen lymph nodes. Movement and mobility: changes in how your pet walks or plays, incoordination, lameness, other signs of pain, swelling, vision changes or seizures. Reproductive and urinary: changes in how often or how much your pet urinates, mammary swelling or ulceration, testicular swelling, or unusual discharge. In the mouth: drooling, changes in eating habits, trouble swallowing, bad breath, losing teeth, or any new masses. None of these signs mean cancer on their own — plenty have far more ordinary explanations. But if something's persistent, new or out of character for your pet, it's always worth a vet visit rather than a wait-and-see. So how much does it cost to treat cancer in pets? Cancer treatment can be genuinely expensive, particularly for the more aggressive cancers that need chemotherapy, radiation or specialist surgery. Current PetSure data shows lymphoma, one of the more commonly treated cancers, averages $6,056 for dogs and $4,327 for cats, with the highest individual claims running well into the tens of thousands. So, what can I do to lower the risk? Feed well, move daily A nutritious diet and regular exercise help your pet maintain a healthy weight and a strong immune system, both of which play a role in reducing certain cancer risks. Knowing what foods to avoid matters just as much as what's in the bowl. Keep the toxins out of reach Household cleaners, toxic plants and some human medications can all increase risk. A quick pet-proofing pass around the house is time well spent. Watch the sun exposure Lighter-coloured pets are more prone to sun-related cancers. Give them plenty of shade, an indoor retreat on hot days, or even a light t-shirt for extra protection if they're prone to sunbaking. FAQs How common is cancer in pets? Cancer is one of the most common health conditions affecting older pets. Research suggests that approximately one in four dogs will develop cancer during their lifetime, making early detection and regular veterinary care especially important. What are the most common types of cancer in dogs? Common cancers diagnosed in dogs include mast cell tumours, lymphoma, sarcoma, carcinoma and osteosarcoma. The type of cancer can influence both treatment options and prognosis. Can cats get cancer too? Yes. Cats can develop a range of cancers, including lymphoma, carcinoma, mast cell tumours, squamous cell carcinoma and adenocarcinoma. Like dogs, early diagnosis can play an important role in treatment outcomes. What are the warning signs of cancer in pets? Potential signs of cancer may include lumps or bumps, unexplained weight loss, changes in appetite, lethargy, vomiting, diarrhoea, difficulty breathing, lameness, swollen lymph nodes, changes in urination or unusual bleeding. Any persistent or unexplained symptoms should be assessed by a veterinarian. Which dog breeds are more likely to develop cancer? While any dog can develop cancer, some breeds may be predisposed to certain cancers. Research has identified breeds such as Boxers, Bernese Mountain Dogs, Bull Mastiffs, Greyhounds and Bull Terriers among those with higher rates of cancer-related claims. Which cat breeds are more prone to cancer? Some cat breeds may have a higher prevalence of cancer than others. Breeds frequently identified in cancer-related claims include Abyssinians, Russian Blues, Siamese, Tonkinese and Maine Coons. How much does cancer treatment cost for pets? Treatment costs can vary significantly depending on the type of cancer, treatment plan and individual pet. Veterinary expenses may include diagnostics, surgery, chemotherapy, radiation therapy, medications and ongoing monitoring. Can cancer in pets be prevented? Not all cancers can be prevented, but maintaining a healthy weight, feeding a balanced diet, encouraging regular exercise, reducing exposure to toxins and protecting pets from excessive sun exposure may help reduce certain cancer risks. Why is early detection important for cancer in pets? Early detection can improve treatment options, help manage symptoms sooner and potentially improve outcomes. Regular veterinary check-ups and monitoring for changes in your pet’s behaviour or health can assist with early diagnosis. Does pet insurance cover cancer treatment? Some pet insurance policies may help cover eligible cancer-related diagnostics and treatments, subject to policy terms, exclusions, waiting periods and benefit limits. Coverage varies between policies and providers.

The C-word: what every pet parent should know about cancer in pets

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