Reutilization of doxorubicin in patients with progressive metastatic breast cancer

Forty patients with progressive metastatic breast cancer were retreated with doxorubicincontaining regimens, following a sustained response to previous doxorubicin-containing chemotherapy. Reintroduction of doxorubicin by intravenous bolus or by continuous infusion occured at a median of 26 mos. (range 4-114 mos.), after the last dose of doxorubicin combination chemotherapy. The dominant sites of involvement were bone, 20; visceral organs, 16 and soft tissue, 4. The response rates to doxorubicin retreatment demonstrated partial response, 30%; no change, 30% and progressive disease, 40%. There were no differences in age, time untill reuse, number of disease sites or duration of response to the first treatment between responders and non-responders to the doxorubicin retreatment. Median total dose of doxorubicin used for responders was 850 mg/m², (from 450 to 1300 mg/m²). Two patients developed clinical evidence of congestive heart failure. In conclusion, doxorubicin-containing chemotherapy can be successfully reutilized by continuous infusion in carefully selected patients with metastatic breast cancer who initially responded to the treatment.