Treatment of “poor risk” acute nonlymphocytic leukemia with continuously infused low‐dose cytosine arabinoside

Abstract

There is currently little experience using a continuous intravenous infusion of low-dose cytosine arabinoside (LDARA-C) in the treatment of acute nonlymphocytic leukemia (ANLL). We report the results in 12 patients with ANLL described as either relapsed ANLL, ANLL with a preceding myelodysplastic phase, or ANLL in the elderly treated with 14 days of continuous intravenous LDARA-C (20 mg/m2/day). Complete responses (CR) were seen in five patients (42%) and partial responses (PR) in three patients (25%). Treatment resulted in overall and clonal cytoreduction, which was evident by serial bone marrow exams and bone marrow cytogenetic analysis. The ability to obtain a CR correlated with the finding of a low initial marrow cellularity (P less than .05). This study finds that continuous intravenous infusion of LDARA-C for ANLL can achieve response rates comparable to standard induction programs in a subset of patients traditionally defined as having a poor prognosis.

High-dose cytosine arabinoside and L-asparaginase therapy for poor-risk adult acute nonlymphocytic leukemia. A retrospective study

“…Earlier reports of CR rates were 0% to 29% with median survivals of only a few month^.^,^^,^^ This led to controversy regarding the optimal therapeutic approach for these patients with advocates for low, standard, and high doses of Ara-C.30-33 These extremely poor response rates in secondary ANLL reported initially included patients treated with varying regimens, often with doses of Ara-C less than 100 mg/m2 and without d a u n~r u b i c i n .~,~~ It appears that protocols employing low-dose Ara-C are less effective than the more aggressive regimens with only 17% to 33% of patients achieving a CR. 4,30,34 Results with standard-dose and HiDAC regimens in secondary ANLL are shown in Table 3. Standard-dose regimens using Ara-C in combination with daunorubicin report response rates of 32% to 36%.4,31 High-dose regimens, with or without L-asparaginase, including the current series, appear to have a variable but higher response rate, 38% to 66%.…”