I don't have much in the way of material assistance to offer, in terms of what herbs, etc to take. Hopefully somebody else with experience in that area can address it.
I can offer some spiritual information, having been in similar circumstances (living with a life threatening illness).
Ask your relative to stop fighting it. Cancer and autoimmune disease are the body's confused response to it's environment. I initially had this reaction, "I'm going to fight," and then I realized I was only fighting myself. If I'm fighting with myself, how can I win?
This may sound "zen" and it probably is, but I have never studied Zen philosophy. I'm just somebody living with a life threatening illness. Once I 'made up' with my body, and befriended the drugs that were keeping me alive, I was free to start exploring other means to heal my body, which eventually led me here.
I am also an 'ex vegetarian' Type O, and would love to speak directly with your uncle/relative (? sorry, I don't have your original post in front of me) about all the confusing information out there about vegetarianism and health.