A phase II trial of esorubicin (4' deoxydoxorubicin) was performed in patients with cancers of the breast, colon, kidney, lung and melanoma. Two partial responses were observed out of 16 patients with breast cancer treated with esorubicin. No objective responses (complete or partial) were seen in patients with colon cancer (18 patients), lung cancer (12 patients), renal cell cancer (12 patients) and melanoma (18 patients). Myelo-suppression was the most significant toxicity encountered with granulocytopenia (neutrophils less than 1,000) observed in 38% of patients. As discussed, we feel that further investigation of esorubicin in anthracycline-sensitive tumors is warranted.