Clinical Study Of Minimal Residual Disease In Acute Lymphblastic Leukemia

Objective: Using two kinds of methods to detect minimal residual .disease(MRD)in acute lymphoblastic leukemia approach the clinical significance of MRD. Method:33 patients with newly diagnosed ALL received 4-6 weeks of remmision-induction chemotherapy .Once complete remission was attained the patients received consolidation therapy .Bone-marrow aspirates were collected after induction theray and during weeks 12, 24 ,36 of continuation therapy .Cells with leukemia associated immunophenotypes were invested by flow cytometery,as immunologic taget of MRD.At the same time , Immunoglobin Heavy chain (IgH) and T Cell Receptor (TCR) gene rearrangement were detected by Polymerase chain reaction(PCR) technique as moleculal taget of MRD. Result: At beginning of disease All of 33 patientsbone marrow express lympho -linge immunophenotype ,At least one of IgH and TCR gene rearrangement were detected in 29/33.after induction theray and during weeks 12, 24 ,36 of continuation therapy,by FCM ,the detectable rates of patients with MRD are 42%. 31%, 16.7%. 12.5%,respectively.By PCR they are41.1% 31.2%, 15.4%. 12.5% At any time , the difference of the detectable rates by thetwo methods is not significant.In different group (based on age, sex ,WBC count,My expression ,PH chromosome CNSL) the difference of the detectable rates is not significance. MRD positive and WBC count more than 50x109 are risk factor of ALL relapse.(P<0.10) .Conclusion: 1 IgH and TCR can be used as gene taget for the detection of MRD in ALL . 2 ALL lassotiated imrnunophynotype can be used as taget for the detection of MRD in ALL.3 The two methods can help each other ,using together can improve the dectectable rates of MRD.4 MRD may be an independent predictor risk of relapse.