Study The Correlation Of Efficacy And Detection Of STR And MRD After NST

Objective To study the correlation of efficacy and detection of STR and MRD after nonmyeloablative allogenic stem cell transplantation(NST). Methods We reports on two patients (CML-CP1,male; CML-CP2,female ), one receiving NST from his HLA matched sibling following conditioning with melphalan (2mg/kg/d×4d)/ ALG(10mg/kg/d×5d) / cyclophosphamide (40mg/kg/d×2d), aother also receiving NST from her HLA unmatched sibling with fludarabine (50mg/d×5d)/ OKT3(10mg/d×4d)/ cytarabine(200mg/kg divide in 4d) / cyclophosphamide (40mg/kg/d×2d)/ melphalan(2mg/kg/d×3d). Prior to infusion, G-CSF (300μg/d) + GM –CSF (300μg/d) mobilized blood stem cells from the 5th day were collected for 3 times. Cycloporine A (CsA) plus methotrexate (MTX) and MMF were used for prophylaxis of GVHD. Patients would be eligible for donor lymphocyte infusion (DLI) given in graded increments according to the chimerism formation and clinical reaction. Engraft assay include the detection of short tandem repeats (STRs), sex chromosome, MRD assay include bcr/abl fusion gene and Philadephia chromosome. Result The first patient got complete chimerism up to +13 month, another evolved from MC to CC on +280d. The first one occurred aGVHD grade IV mainly showing the injury to liver on +28d and it reoccurred on +60d after DLI, and controlled by high-dose methylprednisolone two times and developed chronic GVHD on mucosa skin. The second one died from the relapse. Conclusion It is worthy studying that the relationship between the efficacy and the kinetic monitor of STR and MRD because it is very complicated.