Your insurance company, by law, can't single you out for a rate increase due to this, or any other pre-eisting medical condition. If they raise the rates on your monthly premium, every person that is also insured under the same plan by the same insurance company is also receiving a premium increase at the same time. The insurance companies calculate rate increases by looking at the claims loss history on a particular plan within a given geographical region. If this is an older plan, that is no longer offered by the insurance company, it could be subject to higher rate increases because the people that remain insured under that plan are not able to change coverage due to medical history. I don't know enough about menigioma to understand the short or long term health risks. If, as your doctor says, the risk is minimal, you might consider applying for coverage with a different insurance company. It does seem odd that your insurance company will not let you change coverage to a less comprehensive plan. Try asking them if they have any plans that you can switch to without having to re-qualify.