The ability to manage things like cancer and autoimmune disease depends on a delicate and complex relationship in the body which medicine doesn't really understand and therefore is failing to effectively deal with it.
Managing these diseases depends upon the health of the adrenal glands. Cortisol and Aldosterone are hormones secreted by the adrenal glands. Cortisol in particular, has an anti-inflammatory effect as well as an effect on the function of the immune system itself.
We know that stress leads to high cortisol, which when it is too high it actually damages and weakens the immune system. Long-term very stress leads to exhausted adrenal glands that results in too little cortisol. In this state, the immune system is not just damaged; it actually will cease to function properly at all as long as that state exists.
There will be high inflammation with very low effect. In this state, cancer can go from a small, contained unit, to an explosive disease. Indeed, some researchers feel that no cancer would ever get completely out of control if the adrenals were functioning normally. Low adrenals are not a "cause" of cancer, but when they are not functioning properly, cancer can get out of control.
Generally, cortisol gets lowest after extreme stress has mellowed out. Then, the effect of it "catches up" with the individual. If the person has no cancer existing, this will lead to other problems (such as infection or autoimmune disease) but where cancer is hanging around, an explosion of it may be the result.
This lends credence to New German Medicine that postulates all cancer follows some sort of painful loss, (stress) real or perceived, in the form of money, position or a loved one.
Naturally, a reasonable step, for anyone, is to keep the adrenals supported and to keep cortisol (and other adrenal hormones) within healthy ranges.