Unproven (questionable) cancer therapies.

More than half of all cancer patients use some form of alternative treatment during the course of their illness. Alternative therapies are often started early in patients' illness, and their use is frequently not acknowledged to health care professionals. Some alternative therapies are harmful, and their promoters may be fraudulent. Persons who try alternative cancer therapies may not be poorly educated but may ultimately abandon conventional treatment. Recent attention has focused on aspects of questionable therapies that make these treatments attractive to patients and that may be perceived as being deficient in the practice of conventional health care professionals. Physicians with patients with cancer should always make sure that unproven therapies are discussed early in the therapeutic relationship. They should also attempt to be aware of alternative therapies that are in vogue in their particular geographic area.