Misdiagnosis?

I come from Massachusetts. Beginning about 3 years ago my daughter who was then 15 yrs. old was constantly complaining of headaches. We took her to her PCP who always said that she was going under alot of stress as she was number 3 in her class and was striving to be number 1. The PCP told us to give her "Excedrin Migraine" which helped to relieve the pain, only to wake up the next day with another headache. After a year of this we, her parents, asked for a MRI, CatScan, or something. We were sent to a neurologist who again said it was stress, with no test done at all. In the mean time she was being treated for scolosis and everything was going OK with her back until this past summer. Her curve had gotten worse and she was scheduled for back surgery. When she was having her pre-op tests, which included an MRI of her back and lower skull there was a problem found at the base of the neck. Her brain was being pushed down putting pressure on her spinal column. To correct this she was going to need a type of surgery at the base of the neck to open the area where the spinal fluid sits at the top of the spinal column. A full MRI of her head was ordered by the DR's at the Children's Hospital in Boston. A large brain tumor was found that needed emergency surgery to be removed. I was wondering if there is any merit for a malpractice suit against the PCP and/or original neurologist as they never ordered a simple MRI of her head 2-3 years ago. I was told by the surgeon at the Children's Hospital that this is what they call a "slow grower" meaning it was there for a while. Do I have a case?