It depends on the autoimmune and it, and or how it is being treated. There is a terrible lot to do for it genetics also. It has often been said that one auto immune can open th door to another. All auto immunes are not treated the same. I have more than one...I always say I did not choose my parents well. They Are not necessarily all heredity...I just say that because it's funny to see my Mom get worked up blaming my paternal side because nothing could come from her side (paternal side all gone at this point). And she does not even think at that moment that there she sits with more than one herself. Seriously however,nif you are on immune suppressants you are more prone to viruses. There are many schools of though on cancer origins, the genetic researchers are making huge strides right now In identifying DNA mutations some are familiar some actually are more spontaneous and they don't know if those that mutate more spontaneously come from environmental stress and physical stress or trauma or some other reason but they're saying that it's not all familial. I've also read a ton of articles not recently but it's an articles through time that even tried to link cancer some people saying that it had a viral attribute. I have been doing a lot of research on genetics recently. They have even come up with ways to greatly improve any symptoms, hopefully prevent further damage by, and sometimes repair mutated genes.