Recent advances in adjuvant therapy of breast cancer

Systemic adjuvant therapies that reduce the mortality in breast cancer include ovarian ablation, tamoxifen, and combination chemotherapies. Tamoxifen is effective in reducing the risk of recurrence and death when administered to patients with estrogen receptor-positive tumors. The benefit of tamoxifen was significant, irrespective of age, menopausal status, and whether tamoxifen was given alone or in association with chemotherapy. For patients who had estrogen receptor-poor tumors, there was no significant improvement in disease-free or overall survival. Adjuvant tamoxifen therapy was also associated with a proportional reduction in the incidence of contralateral breast cancer. Anthracycline-containing combination chemotherapy is more effective than other regimens without anthracyclines. Additional alternate treatment with paclitaxel as adjuvant therapy can further reduce the risk of recurrence and improve survival. High-dose chemotherapy remains experimental, and results of ongoing studies will determine its role in the management of primary breast cancer. Escalating doses beyond conventional established doses of currently used chemotherapy drugs does not result in further reduction in risk of recurrence, but adds substantial morbidity as demonstrated by an increased risk of leukemia and myelodysplastic syndrome.