rHuGM-CSF after high-dose chemotherapy in post-remission acute leukemia

Post-remission high-dose chemotherapy has been an important advance in the treatment of adult acute leukemia (AAL). Without the use of colony-stimulating factors (CSFs) in this program, the mortality rate varies from 5 to 17%, and infectious complications arise in more than 50%. These findings limit the widespread use of such forms of therapy. The use of high-dose ara-C (HIDAC) alone or in combination with other drugs is the most common regimen studied, however neither other drug combinations nor the addition of supporting CSFs have been extensively explored. For this reason we studied the effect of high-dose cyclosphosphamide-etoposide (CECY) plus recombinant human granulocyte-macrophage (rHuGM)-CSF with the intention of decreasing morbimortality and prolonging disease-free survival (DFS). Since 1992 we have included 51 complete remission patients with AAL in the CECY plus rHuGM-CSF protocol. The maximal myelosuppression occurred in a mean of 6.4 days, and the mean days required for absolute neutrophil count recovery was 13 days and for platelets 21 days (p < 0.0001). No toxic deaths occurred and only two serious infectious complications were seen. After two years of follow-up, 50% of de novo acute myelogenous leukemia patients had relapsed at 13 months, and 50% of de novo adult acute lymphocytic leukemia patients had relapsed at 15 months. In a recent update, we have not seen a significant difference when compared to historic groups. The CECY protocol does not appear to be superior in prolonging DFS compared to HIDAC as a post-remission strategy for newly diagnosed AAL. The main difference was the absence of toxic deaths and minimal serious infectious complications in the CECY protocol. Therefore, we suggest that the use of rHuGM-CSF in post-remission programs should be included in future studies.