Measurable residual disease study through three different methods can anticipate relapse and guide early interventions in childhood acute lymphoblastic leukemia

Introduction Acute lymphoblastic leukemia (ALL) is the most common cancer among children. Measurable residual disease (MRD, previously named minimal residual disease) study can guide therapy adjustments or preemptive interventions that might avoid hematological relapse. Methods Clinical decision making and patient outcome were evaluated in 80 real-life childhood ALL patients, according to the results observed in 544 bone marrow samples analyzed with three MRD methods: multiparametric flow cytometry (MFC), fluorescent in-situ hybridization (FISH) on B or T-purified lymphocytes and patient-specific nested reverse transcription polymerase chain reaction (RT-PCR). Results Estimated 5 year overall survival and event-free survival were 94% and 84.1%, respectively. A total of 12 relapses in 7 patients were associated with positive MRD detection with at least one of the three methods: MFC (p < 0.00001), FISH (p < 0.00001) and RT-PCR (p = 0.013). MRD assessment allowed the anticipation of relapse and adapted early interventions with different approaches including chemotherapy intensification, blinatumomab, HSCT and targeted therapy to halt relapse in five patients, although two of them relapsed afterwards. Conclusion MFC, FISH and RT-PCR are complementary methods for MRD monitoring in pediatric ALL. Although, our data clearly show that MDR positive detection is associated with relapse, continuation of standard treatment, intensification or other early interventions were able to halt relapse in patients with different risks and genetic background. More sensitive and specific methods are warranted to enhance this approach. However, whether early treatment of MRD can improve overall survival in patients with childhood ALL needs to be evaluated in adequately controlled clinical trials (AU)

Measurable residual disease study through three different methods can anticipate relapse and guide pre-emptive therapy in childhood acute myeloid leukemia

Purpose Although outcomes of children with acute myeloid leukemia (AML) have improved over the last decades, around one-third of patients relapse. Measurable (or minimal) residual disease (MRD) monitoring may guide therapy adjustments or pre-emptive treatments before overt hematological relapse. Methods In this study, we review 297 bone marrow samples from 20 real-life pediatric AML patients using three MRD monitoring methods: multiparametric flow cytometry (MFC), fluorescent in situ hybridization (FISH) and polymerase chain reaction (PCR). Results Patients showed a 3-year overall survival of 73% and a 3-year event-free survival of 68%. Global relapse rate was of 25%. All relapses were preceded by the reappearance of MRD detection by: (1) MFC (p = 0.001), (2) PCR and/or FISH in patients with an identifiable chromosomal translocation (p = 0.03) and/or (3) one log increase of Wilms tumor gene 1 (WT1) expression in two consecutive samples (p = 0.02). The median times from MRD detection to relapse were 26, 111, and 140 days for MFC, specific PCR and FISH, and a one log increment of WT1, respectively. Conclusions MFC, FISH and PCR are complementary methods that can anticipate relapse of childhood AML by weeks to several months. However, in our series, pre-emptive therapies were not able to prevent disease progression. Therefore, more sensitive MRD monitoring methods that further anticipate relapse and more effective pre-emptive therapies are needed (AU)

Trasplante de progenitores hematopoyéticos en niños con ß-talasemia y enfermedad drepanocítica: experiencia del grupo GETMON / Hematopoietic stem cell transplantation in pediatric patients with thalassemia and sickle cell disease: An experience of the Spanish Working Group for Bone Marrow Transplantation in Children (GETMON)

Antecedentes y objetivos: El incremento descrito en la prevalencia de hemoglobinopatías, de ß-talasemia mayor (TM) y de enfermedad drepanocítica (ED) que ha ocurrido en las últimas dos décadas en nuestro país ha generado nuevas necesidades en cuanto a recursos médicos tanto para la prevención como para el tratamiento de estos pacientes. El trasplante alogénico de progenitores hematopoyéticos (alo-TPH) es el tratamiento curativo disponible en nuestro medio para pacientes con hemoglobinopatías graves. El objetivo principal de este estudio fue conocer los resultados del alo-TPH en pacientes pediátricos con TM o ED realizados en unidades de trasplante hematopoyético pediátrico incluidas dentro del Grupo Español de Trasplante de Médula Ósea en Niños (GETMON). Material y métodos: Revisión retrospectiva de los pacientes sometidos a TPH en unidades de TPH del GETMON hasta el año 2015. Resultados: Se analizaron un total de 65 pacientes (43 pacientes afectados de TM y 22 de ED) que recibieron el alo-TPH en 6 unidades GETMON entre noviembre de 1989 y diciembre de 2014. La supervivencia libre de eventos 3años postrasplante fue del 81% y la supervivencia global del 92% en pacientes con TM. La supervivencia libre de eventos 3años postrasplante fue del 79% y la supervivencia global del 85% en pacientes con ED. Conclusiones: Los resultados de esta serie son comparables a los resultados de otras series internacionales y ofrecen un punto de partida para continuar intentando mejorar la evolución de estos pacientes

Background and objectives: A recently occurring increase of the prevalence of haemoglobinopathies, ß-thalassaemia major (TM) and sickle cell disease (SCD) over the last two decades in our country has generated new needs in terms of medical resources for both prevention and treatment of these patients. Allogeneic haematopoietic stem cell transplant (allo-HSCT) is a curative treatment available for patients who have severe haemoglobinopathies. The main objective of this study was to evaluate the results of allo-HSCT in paediatric patients with TM or SCD performed in paediatric hematopoietic transplant units within the Spanish Group of Bone Marrow Transplantation in Children (GETMON). Material and methods: Retrospective review of patients undergoing HSCT in the GETMON units until 2015. Results: A total of 65 patients were analysed (43 patients were affected with TM and 22 with SCD), who received allo-HSCT in 6 GETMON units between November 1989 and December 2014. Event-free survival three years post-transplant was 81% and overall survival 92% in patients with TM. Event-free survival three years post-transplant was 79% and overall survival 85% in patients with SCD. Conclusions: The results of this series are comparable to the results of other international series and offer a platform from which to continue trying to improve the evolution of these patients

Complicaciones neurológicas en población infantil con leucemia / Neurological complications in the population of children with leukaemia

Introducción. La leucemia es el cáncer más frecuente en edad pediátrica. Su tasa de curación es del 80% con quimioterapia intensiva, que mejora la supervivencia, pero que también aumenta la frecuencia de efectos adversos, incluyendo los neurológicos. Objetivos. Describir la frecuencia y características de las complicaciones neurológicas (CN) en pacientes con leucemia aguda linfoide (LAL) y leucemia aguda mieloide (LAM), e identificar los factores asociados a su presencia, la tasa de morbilidad neurológica y la supervivencia. Pacientes y métodos. Estudio retrospectivo de las CN presentes durante el tratamiento y seguimiento de los pacientes con LAL y LAM entre 1997 y 2012 por la unidad de oncohematología infantil. Variables analizadas: datos demográficos, diagnóstico oncológico, tratamiento y CN. Resultados. Se incluyó un total de 157 pacientes, 145 sin infiltración de sistema nervioso central al diagnóstico y ocho con infiltración (tasa de CN del 14 y 12%, respectivamente). Las CN más frecuentes fueron: neuropatías (31%), alteración del nivel de conciencia (27%), convulsiones (22%) y cefalea (12%). Un 40% de los pacientes con CN ha presentado secuelas, pero ninguno ha fallecido como consecuencia de la CN. Se han detectado más CN en el grupo de edad menor de 6 años con LAL de alto grado, en niveles de gravedad más altos y en pacientes que habían recibido trasplante de precursores hematopoyéticos, todas ellas con diferencias estadísticamente significativas. Conclusiones. Las complicaciones neurológicas son frecuentes en los pacientes con leucemia aguda, en especial en aquellos con estadio de riesgo alto (sobre todo si son menores de 6 años) y trasplante de precursores hematopoyéticos. La mortalidad asociada es baja (AU)

Introduction. Leukaemia is the most frequent type of cancer at the paediatric age. The cure rate is 80% with intensive chemotherapy, which improves survival but also often increases the frequency of adverse side effects, including those of a neurological nature. Aims. To describe the frequency and characteristics of the neurological complications (NC) in patients with acute lymphoid leukaemia (ALL) and acute myeloid leukaemia (AML), as well as to identify factors associated to their presence, neurological morbidity and survival rate. Patients and methods. A retrospective study was conducted of the NC present in patients with ALL and AML between 1997 and 2012 treated and followed up by the child onco-haematology unit. The following variables were analysed: demographic data, oncological diagnosis, treatment and NC. Results. Altogether 157 patients were included, 145 without infiltration of the central nervous system at diagnosis and eight with infiltration (rate of NC of 14% and 12%, respectively). The most frequent NC were: neuropathies (31%), altered levels of consciousness (27%), convulsions (22%) and headache (12%). Forty per cent of the patients with NC presented sequelae but none of them died as a consequence of the NC. More NC were detected in the age group of children aged under 6 years with high-degree ALL, at higher levels of severity and in patients who had received a haematopoietic stem-cell transplant, all of them with statistically significant differences. Conclusions. Neurological complications are common in patients with acute leukaemia, especially in those at a high-risk stage (above all if they are under the age of 6 years) and with haematopoietic stem-cell transplant. The associated mortality rate is low (AU)