A weekly schedule of low-dose doxorubicin in treatment of advanced breast cancer.

A phase II study of weekly low-dose doxorubicin (6 to 12 mg/m2) showed it to be an effective, well-tolerated therapy in advanced breast cancer. Although most of the 34 patients studied had been clinically resistant to previous endocrine measures and/or other kinds of chemotherapy, had a median score of 60 on Karnofsky's index, and had predominantly visceral metastases, an objective response was obtained in 20 of 34 patients (four complete remissions, 16 partial remissions) for a median duration of 12+ months. Ten patients experienced no change in their condition for three to 12 months (median, six months). Eight of the 17 patients who had myelosuppression at the beginning of the study had an objective response lasting 4+ to 27+ months (median, 11 months). Eleven of the patients had previously received 500 or more mg/m2 of doxorubicin and were retreated with additional doses of doxorubicin (median cumulative dose, 800 mg/m2) without any clinical signs of toxicity.