Last week Dipsy came in for her first post-surgery check-up. A few days earlier, she had undergone major surgery to have a mastectomy, with most of her mammary glands removed.
Dipsy is a small 12-year-old black and white Shih Tzu. Her owner informed me that she had been developing a swelling in her breasts for the last couple of months. The rate of growth had taken them by surprise. As large as a pear and shaped just like one, even worse, the swelling had now started to leak blood. Dipsy had a very aggressive tumour in her breasts.
Her owners were visibly upset because they were at a loss as to what to do. While wanting to do the right thing by Dipsy, yet fearing that she would not survive such a major operation, they could not bring themselves to think that euthanising their beloved dog might be the kinder thing to do.
I had no doubt about their devotion to little Dipsy, who was so loved by her human family that they had all accompanied her to the clinic to learn her fate.
Mammary tumours are the most commonly occurring tumours in female dogs. They occur more often in dogs that have not been spayed or sterilised, and female dogs that suffer from manifestations of false pregnancy are even more predisposed to suffer from mammary tumours.
False pregnancies occur after their heat when, due to a high level of the hormone progesterone, their body goes through changes just as if it is pregnant.
This phenomenon includes a stimulation of the mammary glands just as if the mother is preparing for puppies. In severe cases, the female dog will even be able to lactate, that is, produce milk from her mammary glands. It is thought that when false pregnancies repeatedly occur, this cyclic stimulation of the mammary glands enhances the possibility of mammary tumours developing.
Mammary tumours in dogs can be either benign or malignant, and can develop from any of the many different cells found within the mammary gland. Rather than its size, the rate with which a tumour grows is often a better indication of how aggressive it is.
Mammary tumours are mostly common in female dogs. They occur more often in dogs that have not been spayed or sterilised
Most of the time, mammary tumours in dogs are benign and tend to spread locally, that is, they stay within the mammary gland, and swellings can be felt in one or more breasts.
Occasionally, we do see canine mammary tumours that are malignant and which either aggressively invade the breasts, the surrounding area or, even worse, spread to other parts of the body.
What was certain with Dipsy was that there was no option available other than a mastectomy. Letting her live with such a large pendulous tumour which was now also leaking blood was not on. Moreover, any further delay would then make it impossible to remove the mammary glands, which already incorporated the larger tumour as well as all the smaller tumours present.
Despite their size, for the time being, they were all situated within the mammary gland tissue, and even though Dipsy’s tumour was very large and there were other smaller swellings located around it, her clinical condition was otherwise very good. Blood tests taken before surgery confirmed that she was in good enough condition to undergo surgery.
Spaying of female dogs which are not intended for mating or suffer from false pregnancy or are over five years of age is certainly indicated to avoid mammary tumours from developing. Whenever a swelling is noticed, it is best to seek the advice of your veterinary surgeon as early as possible to take timely action.
Dipsy’s surgery went well. Because of the size of the tumour, we had to make the most we could of the remaining skin on the breast area to be able to close her up again. Her check-up found that the sutures had held. Dipsy was taking her medication, she had already started to eat, drink and walk normally just three days after surgery. And her owners were far more relaxed about her future.
thisweekwiththevet@gmail.com
Dr Martin Debattista is a veterinary surgeon.