In the mid-1950s, M.D. John Schnidler's How to Live 365 Days a Year introduced readers to the mental factors of illness. He encouraged reducing stress and disease by improving your mental attitude and training yourself out of victim thinking. His methods work well for attitudes and thought patterns you can change consciously. On Amazon.
In 1977, Lawrence LeShan's You Can Fight for Your Life: Emotional Factors in the Treatment of Cancer revealed many of the patterns that make the difference between people who get well from cancer, and those who die. A high percentage of LeShan's terminal cancer patients went into remission or got well, but others died because conventional therapy takes so long to produce results. On Amazon.
In Beliefs: Pathways to Health and Well-Being (1990), Robert Dilts describes how 4 days of NLP healed his mother's cancer, and demonstrates some of the highly effective NLP healing techniques inspired by that success. On Amazon.
In the years since, more NLP health therapies have evolved. With his co-authors Tim Hallbom and Suzi Smith, Dilts teaches NLP Health Certification Training, often described as "the graduate school of NLP." I am a graduate of this training.