Most healthy, active people who eat decently, get enough rest, and avoid drinking and smoking, will be able to eliminate cancer as it comes up. The only people who would benefit from these screenings are already unhealthy and cancer might be just one of many potential conditions they could experience—the goal of healthcare is not to dedicate an inordinate amount of resources for procedures that may amount to not much of any long term benefit.
People talk about the “immune system” but they are really referring to a number of systems the body uses to regulate itself, more or less successfully, around environmental pressures. The body is a system under tension, sometimes extreme tension leads to extreme success (success here being growth of power), sometimes it breaks the body, and sometimes the systems have been slowly failing for a while, and most treatments will not help. Medicine is only useful in the specific case where the power of the body would be promoted if not for one thing, that the body would be healthy, at least manageably so, without that issue.
People talk about the “immune system” but they are really referring to a number of systems the body uses to regulate itself, more or less successfully, around environmental pressures. The body is a system under tension, sometimes extreme tension leads to extreme success (success here being growth of power), sometimes it breaks the body, and sometimes the systems have been slowly failing for a while, and most treatments will not help. Medicine is only useful in the specific case where the power of the body would be promoted if not for one thing, that the body would be healthy, at least manageably so, without that issue.