I would like to add that even in young people, it is very common that there are "copying errors" in the process of mitosis. Is an extremely delicate and complex process subject to failures as everything in the natural world.

The organism for this has certain "emergency" mechanisms to prevent defective genetic material from being reproduced, or even repaired if possible. Roughly, I can mention ras family genes, TGF-beta pathway suppressor proteins, wnt pathway components, and the p53 gene; Very famous the latter, by the way. One could also mention the cellular immunity, represented by CD8 and NK T lymphocytes, which play an important role in the destruction of defective cells (this explains the special tendency of people with AIDS to develop neplasias). Anyway, mistakes can occur, the problem is that if the quality control points of the organism are defective, this genetic material will not be destroyed before it can reproduce.

I also want to make mention of the fact that, while science is certainly not afraid to be questioned - it is the basis of the scientific method - to do so, very well grounded arguments are needed. I would not deny that the cancer moves a multimillion-dollar industry of transnational pharmaceuticals and also many antineoplastic treatment protocols are being modified today thanks to scientific advances, but if anything is certain, we are still far from being able to find a definitive solution. Our only hope is to completely master genetic engineering and nanotechnology.

Needless to say, every human being is a biopsychosocial being, so to focus merely on the biological, as was done in the beginnings of modern medicine, is a mistake, but this should not blind us, it should not make us fall into mystification.