Mammary Cancer in Dogs: Mia’s Story
Mammary gland tumors are the most common type of tumor diagnosed in unaltered female dogs.

Mia’s story
Mia is an 8.5 years old Irish Wolfhound. When she was about 7.5, her mom found a small, pea-sized nodule on her belly. Senior dogs do get the odd lump or bump. It was small so she wasn’t overly worried. Particularly because the nodule wasn’t growing or changing.
“There is never a problem until there is one,” our vet always says.
Your dog could have a hundred lumps that are completely benign. It does not mean that the hundred and first will be benign too.
Mia’s bump starts growing
Then, when she came into heat, Mia’s little quiet bump decided to start growing.
It multiplied in size within a few weeks. Mia’s mom knew she had to take action.
On close inspection it turned out that the original lump was not the only one there; it had the company of several other small bumps.
Mia had mammary cancer.
The heat stimulated its growth.
About half of mammary tumors are benign and remain harmless. The other half are malignant. They grow, spread locally and can spread to other parts of the body such as the liver and lungs.
How does one assess which half the little bump on your dog belongs to?
Nobody can tell without a biopsy. When a little lump decides to start growing, though, the likelihood of it being malignant is high.
That is one downside of having an intact female; it increases the odds of mammary cancer dramatically.
Mia was admitted for surgery and x-rays. She is doing well.
For me, at this day and time, the question isn’t whether or not to spay, merely when. As for lumps and bumps, I take them all seriously, no matter how small.
Jasmine had a bump by her nipple once.
She was about nine years old. She was spayed. But it was a bump. It was tiny, I found it because twice she gave me heck when rubbing her tummy. So we went looking for a reason and found it. Fortunately, in her case, it was just an infection and cleared right up.
Whenever I find the tiniest bump on any of my dogs, I want to KNOW exactly what it is. I’m not taking any chances with bumps.
Source article:
Mia, an eight-year-old Irish Wolfhound who had a lump on her underside
Related articles:
My Dog Has a Lump: See Something, Do Something—Cookie’s Lumpectomy
Further reading:
A Cancer Diagnosis Is Not a Death Sentence