When I went to Mayo, they told me I was the only one under 50 they had seen, and that while this is very rare, it is most common in 70+ individuals. But this is just hearsay on my part.

That's a surprising statement as a doc at mayo has consulted on my daughters case off and on since 2008 and she was 14 when diagnosed and 23 now. We have a private med group of approx 350 members all across the USA and multiple other countries with ages ranging from 18 mos at diagnosis to in the 80s, with many in their 30s and 40s and a handful in their 20s. Many which are or have been treated at mayo.
Lisa

43 here!