Unlikely at this age
Some hemangiomas do "go away" on their own, but this is usually seen in infants.
At age 15, with it enlarging, this would seem unlikely. You are in san fransisco...I would seek an opinion at your university medical center...They may have someone who specializes in the treatment of hemangiomas or "arteriovenous malformations". If not i would start with a dermatologist.