Wiggy,
"however the version of CARI did not calculate exposure to flare events"
I think that you may find that CARI does take flares into account by the use of the 'heliocentric potential'. It's a restrospective factor which is used to cater for the variation of the rate of cosmic radiation. If you look at this site:
http://www.cami.jccbi.gov/AAM-600/Ra.../600radio.html
you can get more background info. You can also subrscribe to the space weather alerting service via a link from that page and then really scare yourself when the sun starts whooping it up on its 11 year solar flare cycle.
There is an aeromed forum hosted elsewhere, where this topic pops up occasionally. From my own research and understanding, I believe that I'm much more likely to die from stress caused by worrying about very low probability events than from the event itself. Life's a dice game after all! Unfortunately, in aviation the game seems to be Craps.
BTW, proportion of western males who die from cancer ~23.5%. Women are a little less likely. However, like many other 'facts' this number varies depending upon your source.