Hi Donna -
First let me say welcome to this site - you have come to a good place that has a lot of good hearted and caring people in my opinion.
I can't answer a lot of your questions about mainstream doctors and treatments, because I represent the other side of the coin here - the natural side that looks to nature, whether first, last or alongside conventional treatments, and encourages everyone here to also look into what natural healing might have to offer.
Obviously, each doctor is going to treat you the way they were trained, and thus there may be differences in virtually identical procedures depending on how they were taught. I would suggest that not only are doctors taught to do things somewhat differently, but when it comes to nature they are taught very little at all.
You said "I find that an informed patient usually does better ...al least for me it works that way . . ." and I find that very encouraging. I believe that a truly informed patient is one who will have left no area unresearched and that will include taking a look at what nature might have to offer in regards to the roles that a good diet, proper nutrition, a clean body and environment, removal of stress, fresh air and water, exercise, a healthy amount of sunshine (yes, even for those with skin cancer), and possibly vitamins, minerals and other supplements may play in building your immune system and helping you fight and ward off cancer.
Most doctors, especially those not trained in diet and nutrition and/or integrative and complimentary therapies, provide little if any information such as I listed above - mainly because that is not yet a part of conventional training (though thankfully it is improving by leaps and bounds). That IS, however, part of my training and experience and I can only urge you to take a good look both inside and outside the box to give yourself the maximum knowledge.
One thing is certain, cancer can only appear when it has managed to defeat the body's first line of natural defense - the immune system. No matter how good of a job mainstream treatments may do at cutting out, burning out or poisoning out the cancer cells themselves, (and often those treatments take a toll on what is likely an already impaired immune system), it is nature that is, in my humble opinion, the best bet to address the underlying causes that led to cancer as well as build up the body to prevent it from returning.
And so, I would say in answer to your most important question of all, about survival rate and long term prospects that the more you bring nature into the process and embrace the idea of beating cancer as a lifelong committment from here out, the greater they will be. I happen to know a number of long term skin cancer survivors- one of whom is my very dear cousin and lifelong running buddy whom was suddenly diagnosed with stage III melanoma.
For more information, I urge you to take a look at these two articles at the very respected (among natural health advocates at any rate) Natural News site:
http://www.naturalnews.com/022808.html
http://www.naturalnews.com/022782.html
Best of wishes to you!