I confess I'm surprised that it's so hard to find statistics of cance by occupation. Wiggy, re your "survey geek" comment it's clear they spread their net as wide as they could given their resources, using social media, unions and dieect approaches in airports. I'm not clear why one would object to the medical conditions being self reported; are you contending that some of the sample might have falsely claimed to have cancer when they don't??