Adjuvant chemotherapy in stage I breast cancer. More harm than benefit.

Clinical trials of adjuvant chemotherapy for breast cancer have shown a prolonged disease-free interval but no improvement in survival. This review of the evidence indicates that adjuvant therapy induces an antineoplastic drug resistance that makes "salvage" therapy less effective. The benefit that is seen only in group statistics, not in an individual, must be weighed against the harm an individual incurs from the chemotherapy.