Networking for advanced molecular diagnosis in acute myeloid leukemia patients is possible: the PETHEMA NGS-AML project

Next-Generation Sequencing has recently been introduced to efficiently and simultaneously detect genetic variations in acute myeloid leukemia. However, its implementation in the clinical routine raises new challenges focused on the diversity of assays and variant reporting criteria. To overcome this challenge, the PETHEMA group established a nationwide network of reference laboratories aimed to deliver molecular results in the clinics. We report the technical cross-validation results for next-generation sequencing panel genes during the standardization process and the clinical validation in 823 samples of 751 patients with newly diagnosed or refractory/relapse acute myeloid leukemia. Two cross-validation rounds were performed in seven nationwide reference laboratories in order to reach a consensus regarding quality metrics criteria and variant reporting. In the pre-standardization cross-validation round, an overall concordance of 60.98% was obtained with a great variability in selected genes and conditions across laboratories. After consensus of relevant genes and optimization of quality parameters the overall concordance rose to 85.57% in the second cross-validation round. We show that a diagnostic network with harmonized next-generation sequencing analysis and reporting in seven experienced laboratories is feasible in the context of a scientific group. This cooperative nationwide strategy provides advanced molecular diagnostic for acute myeloid leukemia patients of the PETHEMA group.

[Clinical and biological prognostic factors in relapsed acute myeloid leukemia patients]. / Factores pronósticos clínico-biológicos en pacientes con leucemia aguda mieloblástica en recaída.

BACKGROUND AND OBJECTIVE: Acute myeloid leukemia (AML) is the most frequent type of acute leukemia in adults. Despite recent advances in the characterization of pathogenesis of AML, the cure rates are under 40%, being leukemia relapse the most common cause of treatment failure. Leukaemia relapse occurs due to clonal evolution or clonal escape. In this study, we aimed to analyze the clinical and biological factors influencing outcomes in patients with AML relapse. PATIENTS AND METHODS: We included a total of 75 AML patients who experienced leukaemia relapse after achieving complete remission. We performed complete immunophenotyping and conventional karyotyping in bone marrow aspirates obtained at diagnosis and at leukemia relapse. RESULTS: Overall survival (OS) of the series was 3.7%±2.3, leukaemia progression being the most common cause of death. Patients relapsing before 12 months and those with adverse cytogenetic-molecular risk had statistically significant worse outcomes. A percentage of 52.5 of patients showed phenotypic changes and 50% cytogenetic changes at relapse. We did not find significant clinical factors predicting clonal evolution. The presence of clonal evolution at relapse did not have a significant impact on outcome. CONCLUSIONS: Patients with relapsed AML have a dismal prognosis, especially those with early relapse and adverse cytogenetic-molecular risk. Clonal evolution with phenotypic and cytogenetic changes occurred in half of the patients without predictive clinical factors or impact on outcome.

Factores pronósticos clínico-biológicos en pacientes con leucemia aguda mieloblástica en recaída / Clinical and biological prognostic factors in relapsed acute myeloid leukemia patients

Fundamentos y objetivo: La leucemia aguda mieloblástica (LAM) constituye la leucemia más frecuente en adultos. A pesar de los avances en el conocimiento de su patogenia, las tasas de curación no superan el 40%, siendo la recaída de la enfermedad la causa más frecuente de fallo de tratamiento. La recaída ocurre por fenómenos de evolución clonal. En este estudio analizamos los factores pronósticos clínicos y biológicos en pacientes adultos con LAM en recaída. Pacientes y métodos: Analizamos un total de 75 pacientes que presentaron recaída leucémica tras haber alcanzado la remisión completa. Se realizó un estudio inmunofenotípico mediante citometría de flujo y estudio citogenético mediante cariotipo convencional en muestras de médula ósea obtenidas en el momento del diagnóstico y de la recaída. Resultados: La supervivencia global (SG) de la serie fue del 3,7%±2,3, siendo la principal causa de muerte la progresión leucémica (83,3%). Los pacientes con recaídas precoces -antes de 12 meses- y aquellos con riesgo citogenético-molecular adverso presentaron SG significativamente inferiores. En el momento de la recaída el 52,5% de los pacientes mostraron cambios fenotípicos, y el 50%, cambios citogenéticos, sin observarse factores clínicos predictivos de dicha evolución clonal. La evolución clonal fenotípica o citogenética no mostró ningún impacto significativo en la SG. Conclusiones: Los pacientes con recaída de LAM presentan un pronóstico infausto, especialmente aquellos con recidiva precoz y riesgo citogenético-molecular adverso. La evolución clonal fenotípica y/o citogenética ocurre en la mitad de los casos sin factores clínicos predictivos ni impacto pronóstico (AU)

Background and objective: Acute myeloid leukemia (AML) is the most frequent type of acute leukemia in adults. Despite recent advances in the characterization of pathogenesis of AML, the cure rates are under 40%, being leukemia relapse the most common cause of treatment failure. Leukaemia relapse occurs due to clonal evolution or clonal escape. In this study, we aimed to analyze the clinical and biological factors influencing outcomes in patients with AML relapse. Patients and methods: We included a total of 75 AML patients who experienced leukaemia relapse after achieving complete remission. We performed complete immunophenotyping and conventional karyotyping in bone marrow aspirates obtained at diagnosis and at leukemia relapse. Results: Overall survival (OS) of the series was 3.7%±2.3, leukaemia progression being the most common cause of death. Patients relapsing before 12 months and those with adverse cytogenetic-molecular risk had statistically significant worse outcomes. A percentage of 52.5 of patients showed phenotypic changes and 50% cytogenetic changes at relapse. We did not find significant clinical factors predicting clonal evolution. The presence of clonal evolution at relapse did not have a significant impact on outcome. Conclusions: Patients with relapsed AML have a dismal prognosis, especially those with early relapse and adverse cytogenetic-molecular risk. Clonal evolution with phenotypic and cytogenetic changes occurred in half of the patients without predictive clinical factors or impact on outcome (AU)