title: Impact of chimaerism analysis and kinetics on allogeneic haematopoietic stem cell transplantation outcome after conventional and reduced-intensity conditioning regimens.
abstract: This retrospective study aimed to analyse the impact on overall survival (OS) and event-free survival (EFS) of chimaerism status and kinetics following allogeneic conventional and reduced-intensity conditioning haematopoietic stem cell transplantation, and to compare this with the impact of other well-known factors. We investigated the chimaerism status of 187 patients [84 females, 103 males; median age 39.5 years (range, 17-62 years)]. After transplantation, 121 patients (65%) presented full donor chimaerism (FDC) and 63 (34%) mixed chimaerism (MC). For MC, we divided the population into patients who presented regressive mixed chimaerism (RMC) (21 patients: 11%), stable mixed chimaerism (SMC) (20 patients: 11%) and progressive mixed chimaerism (PMC) (22 patients: 12%). At last follow-up, 71 patients were alive and 116 had died (48% from disease progression and 52% from transplant-related causes). With a mean follow-up of 39.4 and 34.8 months, the 5-year probabilities of OS and EFS for the total group were, respectively, 55% and 43%: 69.5% and 61% for FDC, 35.4% and 25% for RMC, 42.6% and 28.6% for SMC, and 21% and 10.4% for PMC (P < 0.0001 and P < 0.0001). Multivariate analysis only showed a significant impact of chimaerism status on OS, as well as acute and chronic graft-versus-host disease on EFS, with a trend for conditioning regimen.
authors.affiliation: Department of Haematology, Edouard Herriot Hospital, Lyon 69437, France. annesophie.michallet@voila.fr
authors.forename: Anne-Sophie
authors.initials: AS
authors.lastname: Michallet
authors.forename: Sabine
authors.initials: S
authors.lastname: Fürst
authors.forename: Quoc Hung
authors.initials: QH
authors.lastname: Le
authors.forename: Valérie
authors.initials: V
authors.lastname: Dubois
authors.forename: Aline
authors.initials: A
authors.lastname: Praire
authors.forename: Franck
authors.initials: F
authors.lastname: Nicolini
authors.forename: Xavier
authors.initials: X
authors.lastname: Thomas
authors.forename: Hanadi
authors.initials: H
authors.lastname: Rafii
authors.forename: Lucette
authors.initials: L
authors.lastname: Gebuhrer
authors.forename: Mauricette
authors.initials: M
authors.lastname: Michallet
mesh_terms: D000293:Adolescent; D000328:Adult; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006086:Graft vs Host Disease; D019337:Hematologic Neoplasms / Q000401:mortality / Q000601:surgery*; D018380:Hematopoietic Stem Cell Transplantation / Q000401:mortality*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D012189:Retrospective Studies; D016019:Survival Analysis; D015996:Survival Rate; D018183:Transplantation Chimera; D019172:Transplantation Conditioning / Q000379:methods*; D014184:Transplantation, Homologous