Asking your GP to refer you to another specialist to get a second opinion
If you chose to go down this route it may be best to do some research yourself and actually ask to be referred to a specific person. It may be prudent to have a couple of options as you may not be able to see the doctor of your choice
This method could also delay the start of your cancer treatment so you need to consider it very carefully.
Below is a video made by the UK charity Macmillian Cancer Support. In this video GP David Plume, explains the pros and cons of getting a second opinion through the GP. He is fair in his comments and talks about delays in starting treatments and the effect this may have on your prognosis.
Belgravia Oncology Second Opionion Service
The Belgravia Oncology Second Opinion Service is a private bespoke service that will ensure you get all the information you need about your cancer care. You can continue with your current treatment pathway and there would therefore be no delays whatsoever in your treatment which, like David said, may effect your prognosis.