Spirit vs chemical poisoning
For sure some cancer healings are of a spiritual nature but unfortunately most cancer is caused by chemical poisoning and
parasite infestation. If by a spiritual nature you mean that you have to get tough to turn your back on the Status Quo you are indeed right. Most people worship their doctor more faithfully than any religion and ultimately die thereof. To go the way of Natural Healing as in "the Natural Healing Paradigm" requires you turn your back on orthodox medicine and take full responsibility for your own health. Not an easy task for most people.
If not of a spiritual nature cancer revolves around the health of the liver. Once the liver is healthy I've seen every type of cancer there is resolve and be no more. All the great healers, past and present don't bother with treating the disease. They concentrate on getting a body healthy. For sure there is a mental/spiritual component but most "terminal" folks suffer from niceguyism and are afraid to stand up on their own behalf. If they can get over that, and get tough, and be fully responsible, they'll make it. Sometimes that's all it takes - to get tough. But most of the time there are some nasty chemicals involved and I have yet to see a cancer that didn't involve parasites. So get rid of the bugs, clean the whole show up and decongest the liver. Then if you die of some mysterious disease at least you'll die well fed and clean and you'll know it is truly God calling you home and not a premature death from chemicals,
parasites and a bad attitude.