I cannot remember if surgical removal was an option rawrnr, as this could be a good starting point.
This type of tumor is a sarcoma, and usually cancerous rather than benign.
I would seek help from this website as they are the experts..... http://www.cancertutor.com/
Ive been dealing with this for a year now
IT IS BENIGN!
But HUGE and taking over my space down there...
not attached to anything
PLEASE read my posts from xmas time for more into before helping
THX