Specialist quitting, leaving hight end sales people with a medical degree to fill the gaps.

I think I'll be better off getting somesort of refural from my GP that will let me research and pick a doctor.

giving you the information/care that you want. The problem of that happening to patients is huge in the US. As far as the medication questions go I do have some advice that may help a little. If you get your prescriptions at a local drugstore you can ask the pharmacist for a consultation. There should be no charge on that. They can look at your current prescriptions and tell you about any alternatives if available that would be less of a risk for cancer. They may need to do some further checking to get you the answers but it is their responsibility to do so and they are not supposed to brush you off. Then you could approach your doctor about switching. If you have already asked the pharmacist but didn't get the info you wanted then you could try another pharmacy. If you are getting your prescriptions through a mail-order service you could try calling them and they may be able to provide a consultation or refer you to someone who can answer your questions.

You are perfectly right to ask these questions and you have a right to answers to those questions and to have them provided to you in a courteous, professional and thorough manner. Good luck to you.