http://chronicfatigue.about.com/b/2012/06/08/cancer-risk-linked-to-chronic-fatigue-syndrome.htm In this it says: "Through use of medical records and Medicare claims, researchers discovered the risk of non-Hodgkin lymphoma (NHL), late in life, was 29 times greater in those with ME/CFS. The risk of other forms of cancer did not appear to be elevated." It was pointed out in the comments though that the real risk is still uncertain, this is only a place to start. Based on this http://seer.cancer.gov/statfacts/html/nhl.html it can be seen that the incidence of lymphoma is 19.6 per 100,000 though there are subgroups. Allowing for a tentative 29 fold increase, the incidence of lymphoma in CFS can be approximated to 568 per 100,000. That is about 1 in 176, though the figure may not hold in a younger group or between sexes. Using an age adjusted death rate of 6.6 per 100,000, an estimation of deaths in CFS might be 191 per 100,000. Again, this is only tentative. I mistakenly opened a new thread on this here: http://forums.phoenixrising.me/index.php?threads/lymphoma-more-common-in-cfs.19566/#post-299494 I was interested because of an increased discussion of polycloncal B cell expansion, especially by Lipkin on 18th September speech. Bye, Alex PS Anciendaze pointed out on the other thread that the 29 fold increase is a mistake in the article on this. It was due to a misinterpretation of the figures, and the real increase is very much smaller.