title: Treatment of myelodysplastic syndromes with low-dose oral 6-thioguanine.
abstract: Several cytotoxic agents when used in vitro in very low concentrations have been shown to induce differentiation of leukemic cells. We treated 18 patients with myelodysplastic syndromes with low-dose oral 6-thioguanine (6-TG; 20 to 60 mg daily). Four patients demonstrated significant improvement in peripheral blood counts. An additional three patients had significant reductions in the percentage of leukemic myeloblasts in the marrow without a corresponding improvement in peripheral counts. With the exception of a fall in the peripheral neutrophil count in four patients requiring dose reductions, no toxicity was observed. Low-dose oral 6-TG gives a response rate in myelodysplastic syndromes similar to that of parenteral agents such as cytosine arabinoside. Given the ease of administration and lack of toxicity, oral 6-TG may be a useful treatment modality for these syndromes either alone or in combination with other differentiation-enhancing agents.
authors.affiliation: R. Livingston Ireland Cancer Center, University Hospitals of Cleveland, Case Western Reserve University, OH 44106.
authors.forename: T R
authors.initials: TR
authors.lastname: Spitzer
authors.forename: H M
authors.initials: HM
authors.lastname: Lazarus
authors.forename: E D
authors.initials: ED
authors.lastname: Crum
authors.forename: R
authors.initials: R
authors.lastname: Weisman
mesh_terms: D000284:Administration, Oral; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009190:Myelodysplastic Syndromes / Q000188:drug therapy*; D013866:Thioguanine / Q000008:administration & dosage*
chemical_list: D013866:Thioguanine