Acute monocytic leukemia in children. Response to VP-16-213 as a single agent.

Three patients were studied: two infants with acute monocytic leukemia who failed to respond to the initial combination therapy of daunorubicin with cytosine arabinoside, and an adolescent with relapsed acute monocytic leukemia. They were intensively treated with epipodophyllotoxin (VP-16-213) alone and subsequently had complete remission. One patient showed apparently dose-dependent cytotoxic effect. All three patients have maintained complete remission for 6, 7, and 11 months, respectively. Toxicities, including myelosuppression, alopecia, nausea, vomiting, and renal dysfunction, were well tolerated. Intensive treatment with VP-16-213 alone was thus found to have a potent therapeutic effect on acute monocytic leukemia in children. VP-16-213 deserves a further assessment in the therapeutic protocol for patients with childhood acute monocytic leukemia.