On behalf of my grandmother, we contacted Cancer Treatment Centers in Goodyear AZ regarding her stage 4 lung cancer, as she had seen their advertisements on TV and knew that they worked with advanced cases.
Although she offered to pay for her visit out of pocket (she has Medicare - but apparently that wasn't good enough) they wouldn't even speak to her or look at her file until she had set aside 150K in a special account for them.
The message was pretty clear. Pony up a big wad of cash or we don't want to waste our time with you - even if you are willing to pay for the visit to get a second opinion.
This is a for-profit organization, and as such they serve only the wealthy. While that is their right as a business, I can't say I like it much.