| ObjectiveThe first part of this study aims to investigate the correlation between quantity of circulating myeloma cells(CMCs)and marrow myeloma cells(MMCs)in patients with multiple myeloma(MM)and assess the feasibility of CMCs for reflecting the tumor load and the progression of disease.The second part is to establish a method for enrichment of CMCs from peripheral blood utilizing immunomagnetic beads(IMB),which may benefit for monitoring MRD and relapse in patients with multiple myeloma.Methods(1)Correlation between CMCs and MMCs: The flow cytometry was used to detect the proportions of CMCs and MMCs in 82 patients with MM and 30 patients with anemia but non-plasma cell related disorders.The correlation between quantity of CMCs and MMCs was performed,the difference in each response group was compared respectively and the relationship between CMCs and other prognosis-associated factors was analyzed.(2)U266 cell concentration gradient model was built.FCM was used to detect U266 cells before and after anti-APC IMB selection at every concentration,namely direct FCM group and IMB-FCM group.According to the target antigen CD38-APC/CD138-APC of anti-APC IMB,both groups were divided into CD38-direct-FCM group,CD138-direct-FCM group and CD38-IMB-FCM group,CD138-IMB-FCM group respectively.The percentages of U266 cells were compared between IMB-FCM group and corresponding direct-FCM group respectively.The sensitivity of IMB-FCM for detection of myeloma cells was determined.(3)The bone marrow(BM)and peripheral blood(PB)samples from 32 patients with MM were collected,and then divided into BM-direct-FCM group,PB-CD38-direct-FCM group,PB-CD38-IMB-FCM group,PB-CD138-direct-FCM group and PB-CD138-IMB-FCM group.The myeloma cells were detected in each group.The percentages and positive rates of myeloma cells were compared among PB-IMBFCM group and corresponding PB/BM-direct-FCM group respectively.Results(1)The positive detection rates of CMCs in newly diagnosed and relapsed group and PR group were 71.4%,64.5% respectively.The proportions of CMCs in both groups were positively correlated with those of MMCs(P<0.05).The proportions of CMCs and MMCs in newly diagnosed and relapsed group were significantly higher from PR group to CR group(P<0.0083).No CMCs and MMCs were detected in CR and control group.(2)The rates of elevated ?2-MG,moderate or more anemia,elevated sCrea,renal inadequacy and bone destruction in CMCs positive group were apparently increased as compared with CMCs negative group,which led to higher DS and ISS stage(P<0.05).The multivariate logistic regression analysis indicated that elevated ?2-MG and moderate or more anemia were independent risk factors of the presence of CMCs(P<0.05).(3)The percentages of U266 cells in CD38-IMB-FCM group and CD138-IMBFCM group at every concentration were apparently higher than those in corresponding direct-FCM group respectively(P<0.05).The sensitivity of direct-FCM and IMB-FCM for detection of myeloma cells were 0.01% ? 0.001% respectively.(4)The percentages of myeloma cells in BM-direct-FCM group were significantly higher than those in PB-CD38/CD138-IMB-FCM groups respectively,and the percentages of myeloma cells in PB-CD38/CD138-IMB-FCM groups were significantly higher than those in corresponding PB-direct-FCM group respectively(P<0.0167).The positive rates of CMCs in CD38/CD138-IMB-FCM groups(90.6%,87.5%)were apparently higher than those in corresponding direct-FCM group(65.6%)respectively(P<0.05).Conclusions(1)CMCs could reflect the tumor load and the progression of disease in patients with MM.As compared with MMCs,determination of CMCs to some extent could replace the repeated extraction of bone marrow tests to improve patient compliance.Elevated ?2-MG and moderate or more anemia were independent risk factors of the presence of CMCs for patients with MM.(2)IMB-FCM could increase the positive detection rates of CMCs,the sensitivity of which was 10-fold higher than FCM. |
PDF Full Text Request