Ideally, you should be able to request a consultation/second opinion through your own doctors'; and arrange to have your records sent, ASAP.
They should be as interested in investigating all available treatment options as you are. If not, insist.
It is not an insult to your doctors, or the system, to do so.
New discoveries are being made every day.
Sometimes, it takes an "empowered patient" to gain access to them.