What is a lipoma?
A lipoma is the most common skin tumour found in dogs. They are a benign accumulation of fat cells, which are sometimes called adipocytes. Some dogs may never get one, others pets can become very lumpy because of multiple lipomas.
What does a lipoma look and feel like?
A lipoma is a mass under the skin, which you may notice because the lipoma causes the fur to stick up funny, or you run into the lump when you are petting your dog. Lipomas are usually soft and easily movable; they are not attached to the underlying body wall. Some lipomas can reach giant proportions and cover the entire side of your dog, without causing any medical issues. Veterinarians cannot rely on how the skin mass looks or feels to determine if the mass is a lipoma. Mast cell tumors and soft tissue sarcomas, two potentially malignant tumours, also develop under the skin and can feel soft and squishy just like a lipoma. Dogs can have ten lumps, nine are lipomas and the tenth may be a nasty mast cell tumour.
Should I have my dog’s lipomas removed?
The presence of a lump on your pooch is worrisome to many families, but the vast majority of lipomas never cause a problem in a dog. Occasionally a lipoma becomes very large and interferes with ambulation. These are often found in the armpit and removal improves the dog’s quality of life immeasurably.
Are lipomas ever malignant?
The word, lipoma, implies a benign tumour. However, there is a malignant version of lipoma called a liposarcoma. A liposarcoma is not a lipoma gone bad, but a tumour arising from juvenile fat cells. Dogs affected by a liposarcoma can have a good prognosis, but usually need a major surgical procedure to completely remove the tumour. Dog can also get infiltrative lipomas which can be uncomfortable and require removal. These are often even more challenging to remove, thankfully they are very uncommon.
My dog is really lumpy, now what?
Lipomas are easily diagnosed via cytology (fine needle aspiration ). Cytology can often sort out the difference between mast cell tumors and soft tissue sarcoma as well, but there can be limitations to this type of testing. Talk to your veterinarian or oncologist about any lumps you find on your dog. If the lumps are sometimes hard to find, use a permanent marker or white-out paint/nail polish on the fur to make finding them easier during your pet’s examination.