title: Minimal Residual Disease Detection by Droplet Digital PCR in Multiple Myeloma, Mantle Cell Lymphoma, and Follicular Lymphoma: A Comparison with Real-Time PCR.
abstract: Real-time quantitative PCR (qPCR) is a well-established tool for minimal residual disease (MRD) detection in mature lymphoid malignancies. Despite remarkable sensitivity and specificity, qPCR has some limitations, particularly in the need for a reference standard curve, based on target serial dilutions. In this study, we established droplet digital PCR (ddPCR) for MRD monitoring in multiple myeloma, mantle cell lymphoma, and follicular lymphoma and compared it head-to-head with qPCR. We observed that ddPCR has sensitivity, accuracy, and reproducibility comparable with qPCR. We then compared the two approaches in 69 patients with a documented molecular marker at diagnosis (18 multiple myelomas, 21 mantle cell lymphomas assessed with the immunoglobulin gene rearrangement, and 30 follicular lymphomas with the use of the BCL2/immunoglobulin gene major breakpoint region rearrangement). ddPCR was successful in 100% of cases, whereas qPCR failed to provide a reliable standard curve in three patients. Overall, 222 of 225 samples were evaluable by both methods. The comparison highlighted a good concordance (r = 0.94, P < 0.0001) with 189 of 222 samples (85.1%; 95% CI, 80.4%-89.8%) being fully concordant. We found that ddPCR is a reliable tool for MRD detection with greater applicability and reduced labor intensiveness than qPCR. It will be necessary to authorize ddPCR as an outcome predictor tool in controlled clinical settings and multilaboratory standardization programs.
authors: Division of Hematology, Department of Molecular Biotechnologies and Health Sciences, University of Torino, Torino, Italy. Electronic address: daniela.drandi@unito.it.
authors: Daniela
authors: D
authors: Drandi
authors: Babak Myeloma Group, Department of Pathological Physiology, Faculty of Medicine, Masaryk University, Brno, Czech Republic.
authors: Lenka
authors: L
authors: Kubiczkova-Besse
authors: Division of Hematology, Department of Molecular Biotechnologies and Health Sciences, University of Torino, Torino, Italy.
authors: Simone
authors: S
authors: Ferrero
authors: Bioclarma srl, Torino, Italy.
authors: Nadia
authors: N
authors: Dani
authors: Division of Nuclear Medicine, A.O.U. Città della Salute e della Scienza, Torino, Italy.
authors: Roberto
authors: R
authors: Passera
authors: Division of Hematology, Department of Molecular Biotechnologies and Health Sciences, University of Torino, Torino, Italy.
authors: Barbara
authors: B
authors: Mantoan
authors: Division of Hematology, Department of Molecular Biotechnologies and Health Sciences, University of Torino, Torino, Italy.
authors: Manuela
authors: M
authors: Gambella
authors: Division of Hematology, Department of Molecular Biotechnologies and Health Sciences, University of Torino, Torino, Italy.
authors: Luigia
authors: L
authors: Monitillo
authors: Division of Hematology, Department of Molecular Biotechnologies and Health Sciences, University of Torino, Torino, Italy.
authors: Elona
authors: E
authors: Saraci
authors: Division of Hematology, Department of Molecular Biotechnologies and Health Sciences, University of Torino, Torino, Italy.
authors: Paola
authors: P
authors: Ghione
authors: Division of Hematology, Department of Molecular Biotechnologies and Health Sciences, University of Torino, Torino, Italy.
authors: Elisa
authors: E
authors: Genuardi
authors: Division of Hematology, Department of Molecular Biotechnologies and Health Sciences, University of Torino, Torino, Italy.
authors: Daniela
authors: D
authors: Barbero
authors: Division of Hematology, A.O.U. Città della Salute e della Scienza, Torino, Italy.
authors: Paola
authors: P
authors: Omedè
authors: Bioclarma srl, Torino, Italy.
authors: Davide
authors: D
authors: Barberio
authors: Babak Myeloma Group, Department of Pathological Physiology, Faculty of Medicine, Masaryk University, Brno, Czech Republic; Department of Hematooncology, Faculty of Medicine University of Ostrava and University Hospital Ostrava, Ostrava, Czech Republic.
authors: Roman
authors: R
authors: Hajek
authors: Division of Oncology Department, A.O.U. Città della Salute e della Scienza, Torino, Italy.
authors: Umberto
authors: U
authors: Vitolo
authors: Division of Hematology, Department of Molecular Biotechnologies and Health Sciences, University of Torino, Torino, Italy.
authors: Antonio
authors: A
authors: Palumbo
authors: Hematology Department, S. Maurizio Regional Hospital, Bolzano, Italy.
authors: Sergio
authors: S
authors: Cortelazzo
authors: Division of Hematology, Department of Molecular Biotechnologies and Health Sciences, University of Torino, Torino, Italy.
authors: Mario
authors: M
authors: Boccadoro
authors: Department of Pathology and Laboratory Medicine, New York Presbyterian Hospital-Cornell Medical Center, New York, New York; Division of Pathology, Department of Molecular Biotechnologies and Health Sciences, University of Torino, Torino, Italy.
authors: Giorgio
authors: G
authors: Inghirami
authors: Division of Hematology, Department of Molecular Biotechnologies and Health Sciences, University of Torino, Torino, Italy; Hematology Division, A.O.S. Antonio, Biagio and Cesare Arrigo, Alessandria, Italy.
authors: Marco
authors: M
authors: Ladetto
mesh_terms: D006801:Humans; D008224:Lymphoma, Follicular / Q000175:diagnosis*; D020522:Lymphoma, Mantle-Cell / Q000175:diagnosis*; D009101:Multiple Myeloma / Q000175:diagnosis*; D018365:Neoplasm, Residual / Q000175:diagnosis*; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods; D012015:Reference Standards; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity