Weekly low dose doxorubicin monotherapy in metastatic breast cancer resistant to previous hormonal and cytostatic treatment.

Weekly low dose doxorubicin monotherapy was evaluated in heavily pretreated patients with metastatic breast cancer. 19 patients received 8-12 mg/m2 doxorubicin/week for a treatment period of up to 7 months until a progression of the disease occurred (mean number of weekly courses 15 +/- 8). In 2 of 17 evaluable patients, an objective response with a duration of 3+ and 5 months respectively was achieved. In 9 patients a stabilisation of the disease was observed (mean duration of DS 4 mos +/- 2), whereas the disease progressed in 6. The tolerance for this regimen was remarkable, with neither serious acute toxicity nor any signs of congestive cardiomyopathy even in those patients who were treated beyond a cumulative dose of 450 mg/m2. Weekly low dose doxorubicin monotherapy shows modest activity, but is devoid of severe toxicity in heavily pretreated patients with metastatic breast cancer. An increase in the therapeutic index was not observed.