New and so confused

Percentages are fine when they're just a number on a graph, it's when you become a percentage that it becomes personal. Nobody else can make this decision for you, but yourself, but I agree with @kmakm with the regrets situation. If you choose not to have the chemo and your cancer returns, will you at that point regret not having given it a go? It may or may not have made a difference, but could you be happy with the "what if". I think sometimes that we in the modern society see percentages of 5% as being trivial. If the local shoe shop has adverts in the window of "Today Only.. 5% off all shoes", there is not exactly a stampede into the shop. We think 5%...pfffftttt, not worth the effort, I'll wait till next week and see if they offer more. It you return and see that there has been no further discount, we are not distressed as it was "only" five percent. Five percent of children in a large school of a thousand pupils is fifty. If the parents of a school were told that a deadly disease was going to strike their school, they would be horrified. If they were told a vaccine exists, which has variable side effects, but only offered a five percent extra coverage, they might decide not to vaccinate. However the parents of fifty children who die, might well be left with the "what if". I reckon, do as all the other members above have suggested, look at all your informed options, then make your decision. Remember, we only get one bite of the apple here.