title: Troxacitabine activity in extramedullary myeloid leukemia.
abstract: Troxacitabine is a novel L-enantiomer nucleoside analog with unique properties in terms of its structure, pharmacokinetics, intracellular transport, and susceptibility to mechanisms of resistance. Troxacitabine has significant activity in patients with refractory myeloid leukemias, both as a single agent and when combined with standard anti-leukemia agents. In a cohort of 170 patients with refractory myeloid leukemia treated with troxacitabine-based regimens on Phase 1 or 2 studies, 10 (6%) had biopsy-proven extramedullary disease, either with or without bone marrow involvement. Six of these patients who received single-agent troxacitabine, 4 received a combination of troxacitabine and cytarabine. Complete response and disappearance of all extramedullary lesions were observed in 6 (60%) of these 10 patients. Two of the 6 responding patients relapsed within 3 months, 2 patients had remissions of 8 and 9 months duration, respectively, 1 patient is in on-going remission at 3, and 1 patient is lost to follow-up. Troxacitabine-based therapy had significant antileukemic activity in extramedullary myeloid leukemias and warrants further investigation in this clinical situation.
authors.affiliation: Department of Leukemia, M.D. Anderson Cancer Center, The University of Texas, Houston 77030, USA.
authors.forename: Yesid
authors.initials: Y
authors.lastname: Alvarado
authors.forename: Hagop M
authors.initials: HM
authors.lastname: Kantarjian
authors.forename: Jorge E
authors.initials: JE
authors.lastname: Cortes
authors.forename: Efrosynl
authors.initials: E
authors.lastname: Apostolidou
authors.forename: Carol
authors.initials: C
authors.lastname: Bivins
authors.forename: Francis J
authors.initials: FJ
authors.lastname: Giles
mesh_terms: D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000008:administration & dosage*; D001752:Blast Crisis / Q000188:drug therapy; D003596:Cytosine / Q000008:administration & dosage* / Q000031:analogs & derivatives; D004148:Dioxolanes / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D007951:Leukemia, Myeloid / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D009190:Myelodysplastic Syndromes / Q000188:drug therapy; D012008:Recurrence; D012074:Remission Induction; D016879:Salvage Therapy; D016896:Treatment Outcome
chemical_list: D004148:Dioxolanes; C074908:troxacitabine; D003596:Cytosine