title: Chimerism Analysis of Cell-Free DNA in Patients Treated with Hematopoietic Stem Cell Transplantation May Predict Early Relapse in Patients with Hematologic Malignancies.
abstract: Background. We studied DNA chimerism in cell-free DNA (cfDNA) in patients treated with HSCT. Methods. Chimerism analysis was performed on CD3+ cells, polymorphonuclear (PMN) cells, and cfDNA using 16 small tandem repeat loci. The resulting labeled PCR-products were size-fractionated and quantified. Results. Analyzing samples from 191 patients treated with HSCT for nonneoplastic hematologic disorders demonstrated that the cfDNA chimerism is comparable to that seen in PMN cells. Analyzing leukemia patients (N = 126) showed that, of 84 patients with 100% donor DNA in PMN, 16 (19%) had evidence of clinical relapse and >10% recipient DNA in the plasma. Additional 16 patients of the 84 (19%) showed >10% recipient DNA in plasma, but without evidence of relapse. Eight patients had mixed chimerism in granulocytes, lymphocytes, and plasma, but three of these patients had >10% recipient DNA in plasma compared to PMN cells and these three patients had clinical evidence of relapse. The remaining 34 patients showed 100% donor DNA in both PMN and lymphocytes, but cfDNA showed various levels of chimerism. Of these patients 14 (41%) showed laboratory or clinical evidence of relapse and all had >10% recipient DNA in cfDNA. Conclusion. Monitoring patients after HSCT using cfDNA might be more reliable than cellular DNA in predicting early relapse.
authors.affiliation: Oncology Centre, King Faisal Specialist Hospital and Research Centre, Riyadh 11211, Saudi Arabia.
authors.forename: Mahmoud
authors.initials: M
authors.lastname: Aljurf
authors.affiliation: Pathology and Laboratory Medicine, King Faisal Specialist Hospital and Research Centre, Riyadh 11211, Saudi Arabia.
authors.forename: Hala
authors.initials: H
authors.lastname: Abalkhail
authors.affiliation: Pediatric Hematology/Oncology, King Faisal Specialist Hospital and Research Centre, Riyadh 11211, Saudi Arabia.
authors.forename: Amal
authors.initials: A
authors.lastname: Alseraihy
authors.affiliation: Oncology Centre, King Faisal Specialist Hospital and Research Centre, Riyadh 11211, Saudi Arabia.
authors.forename: Said Y
authors.initials: SY
authors.lastname: Mohamed
authors.affiliation: Pediatric Hematology/Oncology, King Faisal Specialist Hospital and Research Centre, Riyadh 11211, Saudi Arabia.
authors.forename: Mouhab
authors.initials: M
authors.lastname: Ayas
authors.affiliation: Oncology Centre, King Faisal Specialist Hospital and Research Centre, Riyadh 11211, Saudi Arabia.
authors.forename: Fahad
authors.initials: F
authors.lastname: Alsharif
authors.affiliation: Oncology Centre, King Faisal Specialist Hospital and Research Centre, Riyadh 11211, Saudi Arabia.
authors.forename: Hazza
authors.initials: H
authors.lastname: Alzahrani
authors.affiliation: Pediatric Hematology/Oncology, King Faisal Specialist Hospital and Research Centre, Riyadh 11211, Saudi Arabia.
authors.forename: Abdullah
authors.initials: A
authors.lastname: Al-Jefri
authors.affiliation: Oncology Centre, King Faisal Specialist Hospital and Research Centre, Riyadh 11211, Saudi Arabia.
authors.forename: Ghuzayel
authors.initials: G
authors.lastname: Aldawsari
authors.affiliation: Pediatric Hematology/Oncology, King Faisal Specialist Hospital and Research Centre, Riyadh 11211, Saudi Arabia.
authors.forename: Ali
authors.initials: A
authors.lastname: Al-Ahmari
authors.affiliation: Pediatric Hematology/Oncology, King Faisal Specialist Hospital and Research Centre, Riyadh 11211, Saudi Arabia.
authors.forename: Asim F
authors.initials: AF
authors.lastname: Belgaumi
authors.affiliation: Pathology and Laboratory Medicine, King Faisal Specialist Hospital and Research Centre, Riyadh 11211, Saudi Arabia.
authors.forename: Claudia Ulrike
authors.initials: CU
authors.lastname: Walter
authors.affiliation: Pediatric Hematology/Oncology, King Faisal Specialist Hospital and Research Centre, Riyadh 11211, Saudi Arabia.
authors.forename: Hassan
authors.initials: H
authors.lastname: El-Solh
authors.affiliation: Oncology Centre, King Faisal Specialist Hospital and Research Centre, Riyadh 11211, Saudi Arabia.
authors.forename: Walid
authors.initials: W
authors.lastname: Rasheed
authors.affiliation: Hematology/Oncology, NeoGenomics Laboratories, Irvine, CA 92618, USA.
authors.forename: Maher
authors.initials: M
authors.lastname: Albitar