For decades,
maintenance chemotherapy has failed to improve the
cure rate or prolong the
survival of
patients with
acute myeloid leukemia (AML), other than those with
acute promyelocytic leukemia. Immediately after the first complete remission following consolidation
therapy was obtained, oral
maintenance chemotherapy (daily
6-mercaptopurine and weekly
methotrexate) was given and continued for two years in
transplant-ineligible AML
patients.
Leukemia-free
survival (LFS) and overall
survival (OS) were studied and compared between these
patients and the historical
control group who did not receive
maintenance therapy. Consecutive 52
transplant-ineligible AML
patients were analyzed. Among these
patients, 27 received oral
maintenance chemotherapy. No significant difference was found in the
patients' characteristics between the
maintenance and the
control groups. The median OS was 43 (95% CI, 19-67) and 19 (95% CI, 8-30) months in the
maintenance and the
control groups, respectively (P = 0.202). In the
multivariate analysis, the presence of
maintenance therapy was an independent
prognostic factor for better OS (P = 0.021) and LFS (P = 0.024). Clinical benefit from
maintenance chemotherapy was remarkable in older
patients (> or = 60 yr) (P = 0.035), those with intermediate or unfavorable
cytogenetics (P = 0.006), those with initial low blast count in peripheral
blood (P = 0.044), and those receiving less than two cycles of consolidation
therapy (P = 0.017).
Maintenance oral
chemotherapy as a post-remission
therapy can prolong the
survival of
patients with AML
who are not eligible for
transplantation, particularly older
patients, those with intermediate or unfavorable
cytogenetics, those with initial low blast count, and those receiving less than two cycles of consolidation
therapy.