I'm so sorry to hear there is a problem with your daughter. A "mass" on the brain could be many, many things. The term "mass" just means there is an area of something that doesn't look like brain tissue.
It's impossible to know what the problem is or what the options are without more information about your daughter's problems, what the doctors believe the masses are, how large the masses are, whether they are causing pressure on the brain -- and so many more things. You need to press your daughter's doctors for more informations.
Good luck, Quix
So sorry about your daughter, i was 12 when i had a neuroblastoma tumor in my abdomen, and my mom prayed so hard i would live, no chemo and 5 yrs in remission,a nd i am now 41.. Then last summer i found two spots on my brain 1.2 and 1.4 cm on each side , frontal and other.. They said mass effect, i though oh gosh a brain t .. but they say not .. Mine had massaffect, a good neuro and being persistent, will pay off greatly.. I will pray for you.. im not a dr.,. a pateint here. K