García-Gutiérrez, ValentínGómez-Casares, María TPuerta, José MAlonso-Domínguez, Juan MOsorio, SantiagoHernández-Boluda, Juan CCollado, RosaRamírez, María JIbáñez, FátimaMartín, María LRodríguez-Gambarte, Juan DMartínez-Laperche, CarolinaGómez, MontseFiallo, Dolly VRedondo, SaraRodríguez, AliciaRuiz-Nuño, ConcepciónSteegmann, Juan LJiménez-Velasco, Antonio2017-05-052017-05-052017-03-09García-Gutiérrez V, Gómez-Casares MT, Puerta JM, Alonso-Domínguez JM, Osorio S, Hernández-Boluda JC. A BCR-ABL1 cutoff of 1.5% at 3 months, determined by the GeneXpert system, predicts an optimal response in patients with chronic myeloid leukemia. PLoS One. 2017 Mar 9;12(3):e0173532.http://hdl.handle.net/10668/2631Members of the Spanish Group of Chronic Myeloid Leukemia (GELMC) are: Valentín García-Gutiérrez (Hematology Department, Hospital Universitario Ramón y Cajal, Madrid, Spain). María T. Gómez-Casares (Hematology Department, Hospital Universitario Doctor Negrín, Las Palmas de Gran Canaria, Spain). José M. Puerta (Unidad de Gestión Clínica Hematología y Hemoterapia, Hospital Universitario Virgen de las Nieves, Granada, Spain). Juan M. Alonso-Domínguez (Hospital Universitario Fundación Jiménez Díaz, Madrid, Spain). Santiago Osorio (Hematology Department, Hospital Universitario Gregorio Marañón, Madrid, Spain). Juan C. Hernández-Boluda (Hematology Department, Hospital Clínico, Valencia, Spain). Rosa Collado (Genetic Laboratory, Hematology Department, Consorcio Hospital General Universitario, Valencia, Spain). María J. Ramírez (Hematology Department, Hospital de Jerez de la Frontera, Jerez de la Frontera, Cádiz, Spain). Fátima Ibáñez (Hematology Department, Hospital San Pedro de Alcántara, Cáceres, Spain). Alicia Rodríguez (Hematology Department, Hospital Universitario Virgen Macarena, Sevilla, Spain). Concepción Ruiz-Nuño and Antonio Jiménez-Velasco (Hematology Department, Hospital Regional Universitario de Málaga, IBIMA, Spain). Juan L. Steegmann (Hematology Department & IIS-IP. Hospital Universitario de la Princesa, Madrid, Spain.In chronic myeloid leukemia (CML) patients, 3-month BCR-ABL1 levels have consistently been correlated with further outcomes. Monitoring molecular responses in CML using the GeneXpert (Cepheid) platform has shown an optimal correlation with standardized RQ-PCR (IS) when measuring BCR-ABL1 levels lower than 10%, as it is not accurate for values over 10%. The aim of the present study was to determine the predictive molecular value at three months on different outcome variables using the Xpert BCR-ABL1 MonitorTM assay (Xpert BCR-ABL1). We monitored 125 newly diagnosed consecutive CML patients in the chronic phase (CML-CP) using an automated method: Xpert BCR-ABL1. Only 5% of patients did not achieve an optimal response at 3 months, and the 10% BCR-ABL1 cutoff defined by RQ-PCR (IS) methods was unable to identify significant differences in the probabilities of achieving a complete cytogenetic response (CCyR) (50% vs. 87%, p = 0.1) or a major molecular response (MMR) (60% vs. 80%, p = 0.29) by 12 months. In contrast, a cutoff of 1.5% more accurately identified differences in the probabilities of achieving CCyR (98% vs. 54%, p<0.001) and MMR (88% vs. 56%, p<0.001) by 12 months, as well as probabilities of treatment changes (p = 0.005). Therefore, when using the Xpert BCR-ABL1 assay, a cutoff of 1.5% at 3 months could with high probability identify patients able to achieve an optimal response at 12 months.enHumanosLeucemia mielógena crónica BCR-ABL positivaLeucemia mieloide de fase crónicaReacción en cadena de la polimerasaProbabilidadEstándares de referenciaMedical Subject Headings::Organisms::Eukaryota::Animals::Chordata::Vertebrates::Mammals::Primates::Haplorhini::Catarrhini::Hominidae::HumansMedical Subject Headings::Diseases::Hemic and Lymphatic Diseases::Hematologic Diseases::Bone Marrow Diseases::Myeloproliferative Disorders::Leukemia, Myelogenous, Chronic, BCR-ABL PositiveMedical Subject Headings::Diseases::Hemic and Lymphatic Diseases::Hematologic Diseases::Bone Marrow Diseases::Myeloproliferative Disorders::Leukemia, Myelogenous, Chronic, BCR-ABL Positive::Leukemia, Myeloid, Chronic-PhaseMedical Subject Headings::Analytical, Diagnostic and Therapeutic Techniques and Equipment::Investigative Techniques::Genetic Techniques::Nucleic Acid Amplification Techniques::Polymerase Chain ReactionMedical Subject Headings::Analytical, Diagnostic and Therapeutic Techniques and Equipment::Investigative Techniques::Epidemiologic Methods::Statistics as Topic::ProbabilityMedical Subject Headings::Analytical, Diagnostic and Therapeutic Techniques and Equipment::Investigative Techniques::Weights and Measures::Reference Standardsresearch article28278193open access10.1371/journal.pone.01735321932-6203