Don’t just leave us hanging! Would you mind listing some possible reasons to reject cancer treatment in favor of pseudoscience?
"I didn't want my body to be opened... I didn't want to be violated in that way."
It's still not a good reason to avoid surgery, but it's also not a rejection of medical science.
ICU Psychosis is a 'good' example of what kinds of things can happen with patients undergoing lifesaving treatment.
https://www.medicinenet.com/icu_psychosis/article.htm
Here is a story about undergoing ICU Psychosis: https://icupsychosis.blogspot.com/2009/07/my-own-story.html
Even in countries that have functional medical systems, medical treatment can be very de-humanizing. It's not something that may every go away, as medical practice fundamentally clashes with most people's idea of selfhood.
At least with witch doctors, you'll keep your family somewhat calm and won't take a toll on your wallet. More inheritance for them.