It’s everywhere!
Annually in October, Breast Cancer is recognized worldwide and the month celebrated to bring awareness to the disease, raise funds towards survivors and researching the condition. It affects 1 in 8 American women and 1 in 21 Jamaican women, being one of the most common human cancers globally. What many don’t know is that breast cancer can happen in other animals too.
“The Big C” can be very scary in humans, which is why some people avoid using its full name. As far as we know, all body parts can develop cancer and that’s because cancer really refers to the abnormal uncontrolled growth of any type of cell which can be anywhere in the body. The skin, the eyes, the stomach and even the reproductive organs are included. Tumors or masses can be classified as ‘benign’ meaning localized and not cancerous, or ‘metastatic’ meaning cancerous, prone to grow and to spread to other locations. The ability to treat will depend on the stage, size and location and unfortunately in some cases this may not be an option for our animals. This could be due to the effects of the cancer on the body being too rigorous to sustain a good quality of life, the cost of treatment or the owner’s ability to care for the animal.
Mammary Tumors in Dogs
Human females have 2 breasts with 2 nipples. These are our mammary glands for producing milk for our offspring. The equivalent in dogs is found on the belly. Instead of two nipples, there are 6-10, running in two chains, left and right, between the front and back legs.
50% of all cancers in female dogs are mammary and 50% of those are malignant. The exact type of mammary cancer can be determined by taking a sample and analyzing it under a microscope. This allows the veterinarian to establish the type of cells in the mass.
Of all animals, dogs are most frequently affected, with 1 in 4 unspayed females developing the condition in their lifetime. They appear as growths under the skin and one or more glands may be affected. Commonly the glands closest to the rear end of the dog will be involved. Non-specific signs can include painful swollen breasts, abnormal discharge from glands, loss of appetite, weight loss and generalized weakness. Blood sampling will help to give a generalized picture of the functioning of body systems.
Mammary tumors may spread to other locations, most commonly lymph nodes and the lungs so further examination is needed in those areas to determine the extent of the condition. Abdominal ultrasounds and chest radiographs are good diagnostic tools for this.
There’s chemotherapy for human cancer, is there chemotherapy for pets?
In all human medical discoveries we’ve been able to develop some successful therapies, test home remedies and research risk factors, but there is still no true cure for it. The situation is similar in dogs. The use of chemotherapy drugs has been considered however it has not be shown to be very effective for mammary cancer. Other types of cancer can however be treated using this and some with a good success rate.
So what can you do?
Surgical removal is the best option for treatment and depending on the size and location of the mass, it may involve removing just the mass, the mass and associated mammary gland, or even the entire chain. This would mean that an intact female may have less nipples available to suckle any young should she mate. Spaying (surgical removal of the reproductive organs) at the time of mass removal is usually recommended by your veterinarian to reduce the chances of the cancer returning. Remember, there is no cure for this.
How can we prevent breast cancer in dogs?
The Jamaican saying prevention is better than cure is definitely useful here. Spaying before the first heat cycle has proven to reduce the chance of mammary cancer development to 0.5% of that in intact females. If done after the first heat, chances reduce to 8% and then 26% after the third heat (about 2 years old). Especially for owners who want to prevent unplanned pregnancies, this would be an additional benefit. It also reduces the chance of uterine infections.
Purely from a cost perspective, surgery to remove a tumor can be 2-4 times as expensive as having her spayed. The risk of surgery can also be impacted by age and other health conditions. So why not do it sooner then?
Obesity is another risk factor due to higher levels of free estrogen (a reproductive hormone) circulating in the body. The genetic risks and specific dietary contributors are not well understood at this time, however, a balanced diet to promote good body weight and condition can lower the chances of developing cancer.
Life after ‘The Big C’
Removal of mammary cancer can lengthen the lifespan of your dog, though by how long is uncertain and not guaranteed. The extent and stage of malignancy of the cancer will also determine the outcome after surgery, with larger and more widespread cancers, shortening their lifespan. Surgery should be considered if possible to give your dog a chance at a better quality of life, being pain free, with more years to spend with you.
If spaying is done as part of mammary cancer management, you can expect your dog to put on weight a little easier, which will require you to be stricter with her diet. Obesity increases the risk for not just cancer but also for other conditions such as arthritis, liver and kidney problems.
Regular checkups with your veterinarian are important at this point, as they will be able to assess if there is any spread or return of the cancer. Repeated abdominal ultrasounds and chest radiographs are recommended every 3 months in the first year after removal along with palpation of the surgical site and lymph nodes.
Routine Care
Through regular playtime, grooming and belly rubs, you should be able to assess what your dog’s body normally feels like. It’s good to give them a good physical inspection by touching, so that any abnormalities can be detected and discussed with your veterinarian. Scheduling vet visits can also help to identify things you may have missed.
So instead of living in fear of cancer, you can do your best to get ahead of it and now you know what you can do to treat it should it affect your dog.
Till next time ...
Stay Safe Everyone !
Dr. Simone M. Johnally
Veterinarian
Comentários