Improved treatment results in the management of single and multiple relapses of acute lymphoblastic leukemia.

One hundred twenty-five hematologic relapses of acute lymphoblastic leukemia (ALL) were treated with a four-drug reinduction regimen consisting of L-asparaginase, vincristine, daunomycin, and prednisone (Asp-VDP). Complete remission was achieved in 114 of 125 (91%) treatment courses. The regimen also proved to be highly effective in the management of multiple subsequent relapses which occurred in patients who had previously attained complete remissions with this regimen. The rates of remission induction for second and third reinduction attempts were 89% and 90%, respectively. Ten patients received this regimen for the treatment of four or more consecutive relapses and achieved complete remissions on each occasion. Toxicities related to therapy were not excessive. Although myelosuppression was the most frequently encountered toxicity, documented infection complicated only 14% of the treatment courses. These results constitute a considerable improvement in the management of recurrent ALL.