title: Prognostic significance of minimal residual disease in infants with acute lymphoblastic leukemia treated within the Interfant-99 protocol.
abstract: Acute lymphoblastic leukemia (ALL) in infants younger than 1 year is a rare but relatively homogeneous disease ( approximately 80% MLL gene rearranged, approximately 70% CD10-negative) when compared with childhood and adult ALL. Several studies in children and adults with ALL have shown that minimal residual disease (MRD) status is a strong and independent prognostic factor. We therefore evaluated the prognostic significance of MRD in infant ALL. Ninety-nine infant patients treated according to the Interfant-99 protocol were included in this study. MRD was analyzed by real-time quantitative PCR analysis of rearranged immunoglobulin genes, T-cell receptor genes and MLL genes at various time points (TP) during therapy. Higher MRD levels at the end of induction (TP2) and consolidation (TP3) were significantly associated with lower disease-free survival. Combined MRD information at TP2 and TP3 allowed recognition of three patients groups that significantly differed in outcome. All MRD-high-risk patients (MRD levels > or =10(-4) at TP3; 26% of patients) relapsed. MRD-low-risk patients (MRD level <10(-4) at both TP2 and TP3) constituted 44% of patients and showed a relapse-rate of only 13%, whereas remaining patients (MRD-medium-risk patients; 30% of patients) had a relapse rate of 31%. Comparison between the current Interfant-06 stratification at diagnosis and the here presented MRD-based stratification showed that both stratifications recognized different subgroups of patients. These data indicate that MRD diagnostics has added value for recognition of risk groups in infant ALL and that MRD diagnostics can be used for treatment intervention in infant ALL as well.
authors.affiliation: Department of Immunology, Erasmus MC, University Medical Center, Rotterdam, The Netherlands.
authors.forename: V H J
authors.initials: VH
authors.lastname: Van der Velden
authors.forename: L
authors.initials: L
authors.lastname: Corral
authors.forename: M G
authors.initials: MG
authors.lastname: Valsecchi
authors.forename: M W J C
authors.initials: MW
authors.lastname: Jansen
authors.forename: P
authors.initials: P
authors.lastname: De Lorenzo
authors.forename: G
authors.initials: G
authors.lastname: Cazzaniga
authors.forename: E R
authors.initials: ER
authors.lastname: Panzer-Grümayer
authors.forename: M
authors.initials: M
authors.lastname: Schrappe
authors.forename: A
authors.initials: A
authors.lastname: Schrauder
authors.forename: C
authors.initials: C
authors.lastname: Meyer
authors.forename: R
authors.initials: R
authors.lastname: Marschalek
authors.forename: L L
authors.initials: LL
authors.lastname: Nigro
authors.forename: M
authors.initials: M
authors.lastname: Metzler
authors.forename: G
authors.initials: G
authors.lastname: Basso
authors.forename: G
authors.initials: G
authors.lastname: Mann
authors.forename: M L
authors.initials: ML
authors.lastname: Den Boer
authors.forename: A
authors.initials: A
authors.lastname: Biondi
authors.forename: R
authors.initials: R
authors.lastname: Pieters
authors.forename: J J M
authors.initials: JJ
authors.lastname: Van Dongen
mesh_terms: D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D005500:Follow-Up Studies; D015321:Gene Rearrangement; D005803:Genes, Immunoglobulin; D011495:Histone-Lysine N-Methyltransferase; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D051788:Myeloid-Lymphoid Leukemia Protein / Q000235:genetics; D018365:Neoplasm, Residual / Q000175:diagnosis* / Q000188:drug therapy / Q000235:genetics; D016133:Polymerase Chain Reaction; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000175:diagnosis* / Q000188:drug therapy* / Q000235:genetics; D011379:Prognosis; D011948:Receptors, Antigen, T-Cell / Q000235:genetics; D012008:Recurrence; D016896:Treatment Outcome
chemical_list: C497422:KMT2A protein, human; D011948:Receptors, Antigen, T-Cell; D051788:Myeloid-Lymphoid Leukemia Protein; D011495:Histone-Lysine N-Methyltransferase