Locally advanced breast cancer: the contribution of cytotoxic and endocrine treatment to radiotherapy. An EORTC Breast Cancer Co-operative Group Trial (10792).

Patients with locally advanced carcinoma of the breast were randomized to receive either radiotherapy alone, radiotherapy + endocrine therapy, radiotherapy + chemotherapy or radiotherapy + endocrine therapy + chemotherapy. In 363 evaluable patients, time to first progression was delayed significantly by both endocrine treatment and chemotherapy, the greatest effect being achieved by the combination of endocrine treatment and chemotherapy. This effect was almost entirely due to a major effect of systemic treatment on time to loco-regional progression, for which the result is highly significant, rather than time to distant metastasis in which only a non-significant trend was observed. For survival, a trend was seen in favour of the combination of hormone treatment and chemotherapy, but this effect did not achieve statistical significance. This trial suggests that current endocrine and cytotoxic treatments are only of marginal value in improving the prognosis in locally advanced breast cancer.