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.
Cancer 60:2146-2149,1987.
TOPOSIDE (VP-16-2 13: epipodophyllotoxin: 4'-de-
E methyl-epipodophyllotoxin-p-D-ethylidene-gluco-
side) is a semisynthetic derivative of epipodophyllotoxin. It has been demonstrated to be active against testicular small cell carcinoma of the l ~n g , ~. ~ malignant lymphoma,5 malignant histiocytosis6 and leukemia.'-" Although etoposide has an antineoplastic activity as a single agent, it also has a synergistic activity with cytosine arabinoside, cisplatin, cyclophosphamide, and others in several tumors.'2 Among the various types of leukemia in adults, acute monocytic leukemia (AMOL) is most sensitive to VP-16-2 I3 when used alone," although combination chemotherapies such as VP-16-2 I 3 with cyclophosphamide,13,14 VP-16-2 1 3 with azacitidinel5.I6 and A-Triple V1' also have been reported to be effective in childhood acute nonlymphocytic leukemia (ANLL). Only a few reports of childhood AMOL treated with VP-16-2 13 as a single agent have been de-~c r i b e d . ~~~* . ' ~ VP-16-2 13 alone has less side effects in comparison with conventional treatment of ANLL. This report indicates that VP-16-2 1 3 may induce complete remission in children with AMOL who have either a poor response to the initial treatment or a relapse.