The National Cancer Institute (NCI) has several active research projects examining alternative antineoplastic therapies, called the Best Case Series, including studies on homeopathy, insulin-potentiation therapy, and macrobiotic diet. For more details, see http://www.cancer.gov/cancertopics/factsheet/therapy/CAM.
An excellent resource for those interested in primary and secondary prevention is Avoiding Cancer One Day at a Time: Practical Advice for Preventing Cancer, by Lynne Eldridge and David Borgeson.
Post Cancer Treatment
This final category addresses deeper healing issues, achieving balance, and hopefully decreasing the likelihood of recurrence. It has not been well-studied, but it seems that many of the preventive recommendations play a role here and the transformative change that can come from healing practices is a key focus.