Allogeneic and syngeneic marrow transplantation for myelodysplastic syndrome in patients 55 to 66 years of age

We carried out bone marrow transplantation (BMT) in 50 patients with myelod ysplastic syndrome (MDS) who were 55.3 to 66.2 years of age (median, 58.8 y ears). According to the criteria of the French-American-British (FAB) class ification, 13 patients had refractory anemia (RA), 19 had RA with excess bl asts (RAEB), 16 had RAEB in transformation or acute myelogenous leukemia (R AEB-T/AML), and 2 had chronic myelomonocytic leukemia (CMML). According to the recently established International Prognostic Scoring System (IPSS), av ailable for 45 patients, 2 patients were considered low risk; 14, intermedi ate 1 risk; 19, intermediate 2 risk; and 10, high risk. Conditioning regime ns were cyclophosphamide (CY) (120 mg/kg of body weight) plus 12-Gy fractio nated total-body irradiation (FTBI) (n = 15), CY plus FTBI with lung and li ver shielding (n = 4), busulfan (7 mg/kg) plus FTBI (n = 4), or busulfan (1 6 mg/kg) plus CY (n = 27). The busulfan-plus-CY group included 16 patients in whom busulfan was targeted to plasma levels of 600 to 900 ng/mL. In thes e 16 patients, steady-state levels of busulfan actually achieved were 714 t o 961 ng/mL (mean +/- SD, 845 +/- 64 ng/mL; median, 838 ng/mL). The donors were HLA-identical siblings for 34 patients, HLA-nonidentical family member s for 4, identical twins for 4, and unrelated volunteers for 6. AII 46 pati ents surviving > 21 days had engraftment, and 22 patients (44%) are survivi ng 9 to 80 months after BMT. Specifically, among 13 patients with RA, 1 had relapse (cumulative incidence [CI] at 3 years, 8%) and 8 are surviving, fo r a Kaplan-Meier (KM) estimate of survival at 3 years of 59% (disease-free survival [DSF], 53%). Among 19 patients with RAEB, 3 had relapse (CI at 3 y ears, 16%), and 8 are surviving disease free (KM estimate at 3 years, 46%). Among 18 patients with RAEB-T/AML or CMML, 6 had relapse (CI at 3 years, 2 8%), and the KM estimate of DSF at 3 years is 33%. Relapse-free survival ha d an inverse correlation with cytogenetic risk classification and with the risk score according to the IPSS. Survival in ail FAB categories was highes t among patients enrolled in a protocol in which busulfan plasma levels wer e targeted to 600 to 900 ng/mL. These data indicate that BMT can be carried out successfully in patients with MDS who are order than 55 years of age.