Tragically, cancer is a very common problem among our canine companions. Cancer in all its shapes and forms, is an awful disease that touches the lives of hundreds of New Zealanders every year. Sadly, cancer isn’t just something people must do battle with, it’s also a hugely common problem for our canine friends. Cancer is a disease where cells grow out of control and invade surrounding tissues and can spread to other parts of the body.
However getting a diagnosis of cancer doesn’t mean your dog’s life is over, or that there are no treatment options available to help them live out a long and happy life. International research points to cancer as the cause of almost half of all deaths of pets aged 10 years or older and of course dogs are living longer now because of better nutrition and health care. But it can also be a problem in younger, large breed dogs. Cancer is a multifactorial disease, which means it has no known single cause, however, we do know that hereditary or genetic factors as well as environmental factors contribute to the development of cancer in dogs.
Some of the most common forms of cancer that affect dogs in New Zealand
Commonly arise in the lymph nodes, spleen, liver, other organs and the gastrointestinal tract
Mast Cell Tumours
This the most common form of skin cancer that affects our dogs. Mast cells normally occur in the skin, intestines and other tissues
Mammary Gland Tumours
Approximately 1 in 4 un-desexed females suffer from Mammary/breast cancer, and approximately 50 percent of these are malignant.
Soft Tissue Sarcomas
These are malignant cancers that develop in the skin and other connective tissues.
These are more regularly seen in large-breed dogs but can affect any breed. The most common form of bone cancer is called osteosarcoma.
This is a malignant form of cancer that preys on a dog’s blood vessels. It is a common one we see involving older dog’s Spleens and if diagnosed early enough, removing the spleen via surgery may prolong the dog’s life.
We do see pure-breed dogs with a higher incidence of cancer, meaning genetic factors certainly play a role. Mixed breed dogs come from a larger gene pool and are less likely to get genetic-based cancers, but they are still prone to other cancers that arise spontaneously or due to environmental factors. Certain breeds with higher incidence of cancer include German Shepherds, St Bernards, Jack Russell Terriers, Staffordshire Bull Terriers, Rottweilers, Golden Retrievers, Labrador Retrievers, Boxers and Great Danes. Boxers and Staffordshire Bull Terriers commonly get Mast cell tumours, while
Great Danes and Rottweilers commonly suffer bone tumours
Symptoms are variable depending on the type and location of the cancer, and of course the age, breed and sex of the dog. Skin tumours might first present as a lump or bump, while bone tumours in dogs can cause lameness, swelling and are very painful. There may be a range of nonspecific signs that could indicate cancer such as weight loss, a sore that won’t heal, lethargy, exercise intolerance, vomiting, diarrhoea, reduced appetite and coughing. If you notice that your dog is unwell, bring them to the Vet so you can get to the bottom of the problem, as there are a lot of other health problems with these symptoms that are less serious. Also remember that not every lump you notice on the dog can be serious, for example Lipoma’s are benign fat cell tumours and are not of concern unless they grow too big or are in a locality that is going to cause discomfort or become too big, or cause obstruction to circulation(such as on a lower limb).
Don’t despair, many cancers can be dealt with surgically, where masses or tumours are surgically removed with adequate margins to prevent recurrence. The vet can check the severity or spread of the cancer to the lymph nodes, lungs and other abdominal organs such as liver or spleen. The Vet can send biopsies and the tumours removed to the laboratory for diagnosis and often they will tell you the grading of severity of the cancer and in some cases if the surgical margins of tumours has been adequate. The treatment options available to your dog can vary greatly and depend on the type and stage of cancer. Surgical excision, cryotherapy, chemotherapy, radiotherapy, immunotherapy are the most common options. Surgical excision may be all that is needed, whereas more aggressive cancers may require varying combinations of other modalities.
Sadly, another factor many owners need to consider is the cost of treatment, which obviously varies depending on the best treatment option for your pet. The Vet can discuss and give you an estimate of cost for the best treatment option and whatever the decision, the patients quality of life must always be the number one consideration.
THE POWER OF PREVENTION
There are a few things one can do to help prevent some cancers. Mammary and testicular cancer can be prevented by desexing your dog. Early desexing of the bitch before her first heat cycle has been proven, also desexing the male can prevent the male dog getting testicular or prostate hyperplasia or cancer. Also if the male dog has a retained abdominal testicle, it is more prone to going cancerous so should be removed at a young age.
If you are buying a pure bred dog, check its’ parent line to see if there’s a specific kind of cancer in the bloodline.
Early detection is crucial, so you and your Vet can work together to work out the best possible treatment plan.