The place of chemotherapy in the treatment of early breast cancer

Abstract

The choice of systemic treatment for breast cancer depends on the tumour characteristics and stage of disease, and the patient's age, general state of health, menopausal status and oestrogen receptor (ER) status. Traditionally, endocrine therapy has been reserved for post-menopausal women, combination chemotherapy being more commonly used in premenopausal women. Chemotherapy remains the only option for patients with ER-negative breast cancer. The 1992 EBCTCG overview showed that, overall, polychemotherapy as adjuvant treatment for early breast cancer produced significant reductions in annual odds of recurrence and mortality, with a statistically significant trend towards greater benefits in patients aged under 50 years. Several trials have shown combination chemotherapy with cyclophosphamide, methotrexate and 5-fluorouracil (CMF) to be more effective than single-agent chemotherapy in premenopausal women with node-positive tumours. However, although CMF chemotherapy seems to be effective irrespective of menopausal status, this benefit appears greatest in premenopausal women. The addition of anthracyclines to combination chemotherapy regimens has extended disease-free and overall survival rates in both premenopausal and post-menopausal women, including those with ER-positive tumours. The use of high-dose chemotherapy with stem cell support in early breast cancer is unjustified outside the clinical trial setting--current data indicate that such treatment may result in increased morbidity without a reduction in disease recurrence. Tamoxifen is effective in ER-positive disease; however, as yet few large comparative trials have compared endocrine treatment with chemotherapy in early breast cancer. Combination chemoendocrine therapy may provide a greater benefit than tamoxifen alone in early breast cancer, but this requires further study.