Hello Lightbeing,
I'm sorry to hear about your friend.
My brother's best friend (40 years-old) is currently undergoing chemo-therapy for a particularly insidious cancer with a high growth rate. This wonderful man, who only recently married, is now curled up in the fetal position in a London hospital, trying to recover from his first treatment. I suspect all of us have been touched by this blight upon humanity.
Lightbeing, in response to your question; one reason cancer has been so difficult to cure is that there is no such thing as "Cancer." Though cancer in general refers to an out-of-control splitting of cells, every cancer has its unique characteristics. Breast cancer is an entirely different beast than Prostrate cancer for example. This makes a single cure for all cancers that much more difficult to find.
My favorite muse is to imagine that I am president. I probably do this as often as other people imagine what they would do if they won the lottery. Well, one of my first actions as president would be to issue a "JFK like" proclaimation that before this decade is out, we will have conquered all cancers. I would convert our US military to a purely defensive force. I'd scrap NASA's manned space (and only the manned) program. I'd end the so called "war on terrorism" in order to multiply the war on the far greater threat to our well-being. All these moneys saved would go to fund a massive research program to defeat cancers. I'd propose government grants to pay for the entire education of new generations of cancer researchers. I'd bring the brightest minds from all over the planet to these research institutes. It would be the largest enterprise ever undertaken by man. We could do it. All it takes is proper leadership and a will to succeed.
Lightbeing, I extend my best wishes to your friend and to you alike.
Michael