RESUMO
The screening of the BCR::ABL1 kinase domain (KD) mutation has become a routine analysis in case of warning/failure for chronic myeloid leukemia (CML) and B-cell precursor acute lymphoblastic leukemia (ALL) Philadelphia (Ph)-positive patients. In this study, we present a novel DNA-based next-generation sequencing (NGS) methodology for KD ABL1 mutation detection and monitoring with a 1.0E-4 sensitivity. This approach was validated with a well-stablished RNA-based nested NGS method. The correlation of both techniques for the quantification of ABL1 mutations was high (Pearson r = 0.858, p < 0.001), offering DNA-DeepNGS a sensitivity of 92% and specificity of 82%. The clinical impact was studied in a cohort of 129 patients (n = 67 for CML and n = 62 for B-ALL patients). A total of 162 samples (n = 86 CML and n = 76 B-ALL) were studied. Of them, 27 out of 86 harbored mutations (6 in warning and 21 in failure) for CML, and 13 out of 76 (2 diagnostic and 11 relapse samples) did in B-ALL patients. In addition, in four cases were detected mutation despite BCR::ABL1 < 1%. In conclusion, we were able to detect KD ABL1 mutations with a 1.0E-4 sensitivity by NGS using DNA as starting material even in patients with low levels of disease.
Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva , Leucemia-Linfoma Linfoblástico de Células Precursoras , DNA , Resistencia a Medicamentos Antineoplásicos , Proteínas de Fusão bcr-abl/genética , Genômica , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Mutação , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Inibidores de Proteínas Quinases/farmacologiaRESUMO
Our patient is a 36-year-old man referred by his general physician to the Department of Hematology because of mild neutropenia in a routine analysis at work. There was no history of previous diseases, and examination was normal. Blood investigations confirmed the neutropenia and showed elongation of prothrombin time. A bone marrow examination was performed revealing about 10% of myeloblasts on the aspirate smears. A cytogenetic study showed chromosome 16 inversion in all of these cells and tetraploidy only in some of them, which were extremely large in size. According to the revised WHO classification of tumours (2008), the patient was diagnosed as a case of acute myeloid leukaemia with chromosome 16 inversion.