Perhaps a good overview on the discussion of the relationship between cell phone usage and cancer can be found here:
http://www.cancer.gov/cancertopics/factsheet/Risk/cellphones
Well there is no established link between cell phone usage and cancer, there is certainly evidence of widespread social concern and scientific research. It may indeed be the case that cell phone usage that contribute to an increase in cancer morbidity. Still the social concern is there, and it is widespread. And cancer researchers have also shown concern.
More importantly, when a person is diagnosed with cancer a very normal reaction is to look for the cause of the cancer. People want to know, not just that they are sick, but why? What caused it? What did I do? What did I do wrong to suffer this terrible affliction? Do I have myself to blame?
This is a very normal, natural response of a patient when a doctor tells him/her she has cancer. Not to respond this way would appear more "lunatic" than responding so.
I think we should be generous and accommodating with victims of cancer with regard to their disease, be it Sheryl Crow, Lance Armstrong, or anyone else. Disease is perhaps our one common enemy.