A study reported by Barbara Anderson PhD in August 1999 at the annual meeting of the American Psychological Association, found that training of cancer patients in relaxation, stress reduction and strategies for coping not only helps in improving patient outlook during treatment, but shows indications of aiding in fighting breast cancer.

Those on the intervention program had lower levels of the stress hormone cortisol which is known to suppress the immune system function.
The group that learned new skills was better able to tolerate the full dosage of chemotherapy.
Those who learned new skills were nearly twice as likely to follow through with the full chemotherapy regime.