Fluorescence in situ hybridization detected minimal residual disease and chimerism in patients with hematologic malignancies after allogeneic hematopoietic stem cell transplantation / 中华器官移植杂志

ABSTRACT

Objective To explore the minimal residual disease (MRD) and cellular chimerism in patients with hematopoietic malignancies after allogeneic hematopoietic stem cell transplantation (allo-HSCT).Methods From May 2001 to June 2005,83 patients received allo-HSCT,including 55 males and 28 females. Of them 49 patients received sibling HLA-matched bone marrow transplantation (BMT),3 HLA-matched peripheral blood stem cell transplantation,8 un-related BMT,9 nonmyeloablative stem cell transplantation (NST) and 14 related haploidentical transplantation. Among them,49 patients were diagnosed as having CML,16 having AML,16 having ALL,one having multiple myeloma and one having malignant lymphoma. Chimerism and MRD were monitored by fluorescence in situ hybridization (FISH) using X and Y specific centromeric probes or gene probes for BCR/ABL,MLL and AML1/ETO. 1000 cells were analyzed for each sample.Results Among 19 patients receiving sex-matched transplant,the former chromosome rearrangements were not found in 16 patients after transplantation,MRD was detected in 10 % of cells in one patient and 1 % of cells having MRD in 4th month after the reduction of immunotherapy,and the patients were still in remission one year after transplantation. Two patients were found having the former chromosomal rearrangement 1 and 4 months after transplantation,respectively,who did not achieve remission after chemotherapy. Over 99 % donor chimerisms were found in 50 patients on day 25,donor cells were at a low level ( 96.2 % ~ 98.7 % ) in 7 patients on day 25,and increased over 99 % later. They were in remission without relapse. The donor chimerisms were decreased gradually in other 7 patients,of them 3 patients with the host cells above 10 % showed hematologic relapse. Four patients with the host cells between 2 %~5 % had different outcomes: 2 patients died of severe GVHD after the reduction of cyclosporine A,one patient got a donor chimerism over 99 % after reduction of immunotherapy,and one patient was still in complete remission.Conclusions FISH could play a pivotal role in the detection of MRD and chimerism. It is helpful to the evaluation of graft and relapse and to the guide of intervention of early immunotherapy.