posted at 11/20/2010 10:38 AM ESTWhat are they caused from? is there anything we can do to prevent them?My 8 year old Border Collie has 4 quarter size "fatty mass's" on various parts of her body which have developed in the last 6 months. We had a very large one removed from her left shoulder joint six months ago because it was causing her to limp.
Re: fatty masses
posted at 11/24/2010 2:44 PM ESTAnswer by Dr. Mara Ratnofsky of Angell Animal Medical Center's General Medicine Service:
The causes behind fatty masses remain widely unknown however there are certain factors that align with their appearance. The vast majority of fatty masses appear in dogs of certain breeds, middle aged to older canines, and overweight female dogs. Unfortunately there are not yet any proven methods to prevent fatty masses in dogs.
Many fatty masses are benign forms of lipoma including infiltrative lipomas that can invade surrounding tissues including muscles and bones. Forms of infiltrative lipomas can affect the functions of tissues requiring surgical removal as well as radiation treatment to prevent a returning growth.
While the majority of these masses can be benign, some growths may be liposarcomas, a rare form of cancerous fatty tumors. Since liposarcomas can be life threatening, it is always crucial to have new masses examined by your dog’s veterinarian. Fatty masses cannot be diagnosed simply by viewing or touching them, so be sure that a veterinarian aspirates all new masses.
Since many fatty masses are benign, treating them is usually not necessary unless they are growing rapidly, bothering your dog, or limiting mobility as you mentioned. Your awareness of these masses on your dog is important so that you can monitor for new growths and growth rate.