Was your previous doctor a pituitary specialist? Were you tested for all types of tumors? Were your scan dynamic (contrast given during the MRI not pulled out to give it) as that shows smaller lesions?
During your annual exams, what blood tests were done?
A tumor without treatment can return (sometimes with!). I am only a layman but I had a couple of pituitary tumors myself - but one of my tumors hid for 12 years and only showed up when a pituitary center did a proper dynamic scan. So your tumor may have always been there?
Treatments all depend on the type of tumor and that can only be determined by lab testing. I hope you see a good neuro-endo and get the lab testing you need (get copies!) so the type of tumor is determined, and from there, the proper treatment can be discussed with your doctor.
Dear gp35
I have to agree 100% with rumpled. The tumor could have been there during these years. They can be hard to see in regular MRIs.
When they are small the only formal indication for surgery is if the tumor secrets, meaning functional. If it is large and pushing on thE optic nerves, then the treatment is surgery unless it is a prolactinoma that can be treated by medication.