Spaceman let us see some evidence for your allegations, please. It seems to me that you have heard a few rumours, decided that they're facts, embroidered them a bit - no, a lot - and concluded that all airline pilots are about to expire through various cancers.
Let me help you a little: in my airline we continuously monitor radiation exposure to pilots and cabin crew through the use of specialist monitoring equipment on one or two aeroplanes, and the extrapolation of their findings to all our crew. No crewmember is allowed to exceed the statutory raditation limits applied to all workers in at-risk fields. In fact, our results show that no crew member has reached more than (if I remember correctly) half of the maximum exposure in any given period. The crew most exposed are the Japanese national cabin crew who work exclusively on LHR-NRT flights, which fly at high latitudes (where atmospheric protection is less effective) and at high altitudes (FL380+). The vast majority of our crew, who cover a wider route structure, are way, way below the statutory limits.
Cancer is not more common among crew in our airline than in the general population. In fact, our workforce must be particularly fit and healthy as illness of any kind is lower than the general population. In my seven years in the airline, I don't believe any pilot has died of cancer, though one has been diagnosed of bowel cancer and is now in remission. I am aware of one cabin crew member who has.
These, Spaceman, are facts. Something which you patently are not familiar with, and prefer to replace with your prejudices. You, and your conspiracy theories, are far more damaging to our profession than any cancer.
Scroggs