[C]ancer cell survival can be traced to the presence of heat shock factor-1, which previous research has linked to stress. Ohio State University researchers first noticed that this common protein can help heart tissue survive in a toxic environment, leading the scientists to suspect that in cancer, this phenomenon could have serious consequences.I will have to hazard a guess here, not having had any personal experience in the matter, but I would think that one of the greatest stresses one could possibly have is living with a cancer diagnosis, and that the days leading up to one's treatment, in which one expects to be injected with deadly poisons or bombarded by deadly X-rays, are not likely to be stress-free either. It is very difficult to be equanimous when one is living in fear of losing one's life or in fear of significant and impending discomfort or pain.
A series of experiments using breast cancer cells showed that a protein activated by the presence of heat shock factor-1 could block the process that kills cancer cells even after the cells’ DNA was damaged by radiation. The same was true when the cells were subjected to a common chemotherapy drug.
The researchers hope to develop a drug that could suppress heat shock factor-1 as a supplement to cancer therapy, but in the meantime, they recommend that patients avoid both psychological and physical stress in the days leading up to a cancer treatment.
And leaving conventional cancer treatments aside, I would also wonder what kind of effect this same stress would have on alternative cancer treatments, whatever they may be, and what kind of effect removing stress from one's life would have on one's survival from cancer, with or without treatment.