Dihydroxyanthracenedione: A promising new drug in the treatment of metastatic breast cancer

Thirty-one patients who had metastatic breast cancer extensively pretreated with combination chemotherapy, including doxorubicin, were treated with dihydroxyanthracenedione, 3 to 4 mg/m² body surface area daily for 5 consecutive days every 4 weeks. Of 27 evaluable patients, one achieved a complete response and five had partial responses. Furthermore, responses were seen in patients who were refractory to doxorubicin, indicating a lack of cross-resistance between doxorubicin and dihydroxyanthracenedione. Acute drug toxicity was insignificant except for severe granulocytopenia at the dose level of 4 mg/m².d. The median duration of remission had not been reached, but was more than 26 weeks, with four of the six responding patients still in remission at last follow-up. We believe that dihydroxyanthracenedione has significant activity against refractory metastatic breast cancer and further evaluation is warranted.