Cancer — the signs

Up to 80 percent of skin lumps in pets turn out not to be cancerous. Lipomas — soft, movable fatty lumps — are extremely common and harmless. Every sign on this page can also be caused by something ordinary. The point is not to frighten you into reading lumps as doom; it is that you cannot tell by feeling, and neither can your vet, which is why the answer is always a test rather than a guess.

Note: Adapted from the American Veterinary Medical Association's list, which most veterinary oncology centers use.

Signs: · A lump or swelling that is enlarging, changing shape or texture, or is new
· Sores that do not heal within a couple of weeks
· Weight loss with no change in diet
· Loss of appetite, or eating noticeably less
· Bleeding or discharge from any body opening
· An offensive odor, particularly from the mouth, nose or rear
· Difficulty eating or swallowing
· Hesitation to exercise, or a loss of stamina you cannot explain
· Persistent lameness or stiffness
· Difficulty breathing, urinating or defecating

Why monthly: A change is easier to notice than a lump. If you check every month you will catch something growing; if you check once a year you will only find things that are already obvious.

How to do it: Five minutes, while they are relaxed. Run both hands slowly over the whole dog — head, jaw, neck, shoulders, chest, back, belly, all four legs, tail, and between the toes. Lift the lips and look at the gums. This doubles as a bonding session and most dogs love it.

The lymph nodes to know: Four places you can feel them: under the jaw, in front of the shoulders, in the armpits, and behind the knees. Enlarged nodes in several of these at once is one of the most common ways lymphoma is caught. Learn what normal feels like now, so you know when it changes.

Record what you find: Photograph anything you find with a coin beside it for scale, and note the date and location. ‘It might be a bit bigger’ is not useful to a vet; a photo from six weeks ago is.

Usually a fine needle aspirate first — a small sample drawn with a needle, often without sedation, read under a microscope. It is quick, cheap relative to everything else, and it answers the question. If that is inconclusive, a biopsy follows. The line worth remembering, from an oncology center: lumps belong in biopsy jars, not on pets.

Golden Retrievers and Boxers for several cancers; Bernese Mountain Dogs for histiocytic sarcoma; Scottish Terriers for bladder cancer; and large and giant breeds, including Greyhounds, Rottweilers and Great Danes, for osteosarcoma. Higher risk is not destiny — but if you have one of these, the monthly check matters more, and persistent limping in a large breed deserves an x-ray rather than rest and waiting.

· Keeping them lean. Obesity is linked to several cancers and it is free to address.
· Not smoking around them — secondhand smoke is associated with nasal and lung cancer in dogs
· Limiting lawn chemical exposure. See yard chemicals and your dog for what the studies found.
· Spay and neuter timing, which changes risk in both directions depending on the cancer and the breed — a conversation with your vet rather than a rule
· Annual exams for adults and twice yearly for seniors, with bloodwork. Many cancers are found on routine panels before any sign appears.

Book an appointment rather than waiting to see. Waiting is the only thing on this page that reliably makes the outcome worse, and a fine needle aspirate on something harmless costs far less than a month of worrying about it.

The monthly check costs nothing and finds more than anything you can buy. There is no product on this page.

· American Veterinary Medical Association (avma.org) — the ten warning signs
· Flint Animal Cancer Center, Colorado State University (csuanimalcancercenter.org)
· Morris Animal Foundation Golden Retriever Lifetime Study — the largest prospective canine health study running
· Veterinary Cancer Society (vetcancersociety.org) — find a board-certified veterinary oncologist