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)

A Newborn Screening Program for Sickle Cell Disease in Murcia (Spain).

Sickle cell disease (SCD) is an inherited autosomal recessive hemoglobin disorder caused by the presence of hemoglobin S, a mutant abnormal hemoglobin caused by a nucleotide change in codon 6 of the ß-globin chain gene. SCD involves a chronic inflammatory state, exacerbated during vaso-occlusive crises, which leads to end-organ damage that occurs throughout the lifespan. SCD is associated with premature mortality in the first years of life. The process of sickling provokes asplenia in the first years of life with an increased risk of infection by encapsulated germs. These complications can be life-threatening and require early diagnosis and management. The most important interventions recommend an early diagnosis of SCD to ensure that affected newborns receive immediate care to reduce mortality and morbidity. The newborn screening program in the region of Murcia for SCD began in March 2016. We aimed to determine the incidence of sickle cell anemia and other structural hemoglobinopathies in the neonatal population of the region of Murcia, an area of high migratory stress, and to systematically assess the benefit of newborn screening for SCD, leading to earlier treatment, as well as to offer genetic counseling to all carriers. The prevalence of SCD in our region is similar to others in Spain, except for Catalonia and Madrid. The newborns with confirmed diagnoses of SCD received early attention, and all the carriers received genetic counseling.

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)

New Cases of Hypochromic Microcytic Anemia Due to Mutations in the SLC11A2 Gene and Functional Characterization of the G75R Mutation.

Divalent metal-iron transporter 1 (DMT1) is a mammalian iron transporter encoded by the SLC11A2 gene. DMT1 has a vital role in iron homeostasis by mediating iron uptake in the intestine and kidneys and by recovering iron from recycling endosomes after transferrin endocytosis. Mutations in SLC11A2 cause an ultra-rare hypochromic microcytic anemia with iron overload (AHMIO1), which has been described in eight patients so far. Here, we report two novel cases of this disease. The first proband is homozygous for a new SLC11A2 splicing variant (c.762 + 35A > G), becoming the first ever patient reported with a SLC11A2 splicing mutation in homozygosity. Splicing studies performed in this work confirm its pathogenicity. The second proband harbors the previously reported DMT1 G75R mutation in homozygosis. Functional studies with the G75R mutation in HuTu 80 cells demonstrate that this mutation results in improper DMT1 accumulation in lysosomes, which correlates with a significant decrease in DMT1 levels in patient-derived lymphoblast cell lines (LCLs). We also suggest that recombinant erythropoietin would be an adequate therapeutic approach for AHMIO1 patients as it improves their anemic state and may possibly contribute to mobilizing excessive hepatic iron.

Expression of NK Cell Receptor Ligands on Leukemic Cells Is Associated with the Outcome of Childhood Acute Leukemia.

Acute leukemia is the most common malignancy in children. Most patients are cured, but refractory/relapsed AML and ALL are the first cause of death from malignancy in children. Maintenance chemotherapy in ALL has improved survival by inducing leukemic cell apoptosis, but immune surveillance effectors such as NK cells might also contribute. The outcome of B-ALL (n = 70), T-ALL (n = 16), and AML (n = 16) pediatric patients was evaluated according to leukemic cell expression of ligands for activating and inhibiting receptors that regulate NK cell functioning. Increased expression of ULBP-1, a ligand for NKG2D, but not that of CD112 or CD155, ligands for DNAM-1, was associated with poorer 5-year event-free survival (5y-EFS, 77.6% vs. 94.9%, p < 0.03). Reduced expression of HLA-C on leukemic cells in patients with the KIR2DL1/HLA-C*04 interaction was associated with a higher rate of relapse (17.6% vs. 4.4%, p = 0.035) and lower 5y-EFS (70.6% vs. 92.6%, p < 0.002). KIR2DL1/HLA-C*04 interaction was an independent predictive factor of events (HR = 4.795, p < 0.005) or death (HR = 6.731, p < 0.005) and might provide additional information to the current risk stratification. Children who carry the KIR2DL1/HLA-C*04 interaction were refractory to current chemotherapy treatments, including allogeneic stem cell transplantation; therefore, they should be considered as candidates for alternative biological therapies that might offer better results.

Hereditary Hyperferritinemia Cataract Syndrome: Ferritin L Gene and Physiopathology behind the Disease-Report of New Cases.

Hereditary hyperferritinemia-cataract syndrome (HHCS) is a rare disease characterized by high serum ferritin levels, congenital bilateral cataracts, and the absence of tissue iron overload. This disorder is produced by mutations in the iron responsive element (IRE) located in the 5' untranslated regions (UTR) of the light ferritin (FTL) gene. A canonical IRE is a mRNA structure that interacts with the iron regulatory proteins (IRP1 and IRP2) to post-transcriptionally regulate the expression of proteins related to iron metabolism. Ferritin L and H are the proteins responsible for iron storage and intracellular distribution. Mutations in the FTL IRE abrogate the interaction of FTL mRNA with the IRPs, and de-repress the expression of FTL protein. Subsequently, there is an overproduction of ferritin that accumulates in serum (hyperferritinemia) and excess ferritin precipitates in the lens, producing cataracts. To illustrate this disease, we report two new families affected with hereditary hyperferritinemia-cataract syndrome with previous known mutations. In the diagnosis of congenital bilateral cataracts, HHCS should be taken into consideration and, therefore, it is important to test serum ferritin levels in patients with cataracts.

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

L-Ferritin: One Gene, Five Diseases; from Hereditary Hyperferritinemia to Hypoferritinemia-Report of New Cases.

Ferritin is a multimeric protein composed of light (L-ferritin) and heavy (H-ferritin) subunits that binds and stores iron inside the cell. A variety of mutations have been reported in the L-ferritin subunit gene (FTL gene) that cause the following five diseases: (1) hereditary hyperferritinemia with cataract syndrome (HHCS), (2) neuroferritinopathy, a subtype of neurodegeneration with brain iron accumulation (NBIA), (3) benign hyperferritinemia, (4) L-ferritin deficiency with autosomal dominant inheritance, and (5) L-ferritin deficiency with autosomal recessive inheritance. Defects in the FTL gene lead to abnormally high levels of serum ferritin (hyperferritinemia) in HHCS and benign hyperferritinemia, while low levels (hypoferritinemia) are present in neuroferritinopathy and in autosomal dominant and recessive L-ferritin deficiency. Iron disturbances as well as neuromuscular and cognitive deficits are present in some, but not all, of these diseases. Here, we identified two novel FTL variants that cause dominant L-ferritin deficiency and HHCS (c.375+2T > A and 36_42delCAACAGT, respectively), and one previously reported variant (Met1Val) that causes dominant L-ferritin deficiency. Globally, genetic changes in the FTL gene are responsible for multiple phenotypes and an accurate diagnosis is useful for appropriate treatment. To help in this goal, we included a diagnostic algorithm for the detection of diseases caused by defects in FTL gene.

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). / Trasplante de progenitores hematopoyéticos en niños con ß-talasemia y enfermedad drepanocítica: experiencia del grupo GETMON.

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.

Type III pleuropulmonary blastoma in a dicer1 germline mutation carrier: The management of residual lung cystic lesions.

Pleuropulmonary blastoma (PPB) is a rare malignancy of childhood. It often represents a manifestation of a hereditary tumor predisposition syndrome (DICER1 syndrome). Because of its malignant potential, surgical resection of cystic lung lesions is recommended in germline DICER1 mutation carriers. We present a case of a 3-year-old male child with type III PPB successfully managed with ifosfamide, vincristine, actinomycin-D, and doxorubicin (IVADo) chemotherapy and surgery. A heterozygous germline pR688X mutation of DICER1 gene was demonstrated. Six years after primary diagnosis, several small lung cysts remained stable without further therapy. The management of residual asymptomatic lung cysts represents a clinical challenge in 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)

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

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.

TITLE: Complicaciones neurologicas en poblacion infantil con leucemia.Introduccion. La leucemia es el cancer mas frecuente en edad pediatrica. Su tasa de curacion es del 80% con quimioterapia intensiva, que mejora la supervivencia, pero que tambien aumenta la frecuencia de efectos adversos, incluyendo los neurologicos. Objetivos. Describir la frecuencia y caracteristicas de las complicaciones neurologicas (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 neurologica y la supervivencia. Pacientes y metodos. 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 oncohematologia infantil. Variables analizadas: datos demograficos, diagnostico oncologico, tratamiento y CN. Resultados. Se incluyo un total de 157 pacientes, 145 sin infiltracion de sistema nervioso central al diagnostico y ocho con infiltracion (tasa de CN del 14 y 12%, respectivamente). Las CN mas frecuentes fueron: neuropatias (31%), alteracion 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 mas CN en el grupo de edad menor de 6 años con LAL de alto grado, en niveles de gravedad mas altos y en pacientes que habian recibido trasplante de precursores hematopoyeticos, todas ellas con diferencias estadisticamente significativas. Conclusiones. Las complicaciones neurologicas 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 hematopoyeticos. La mortalidad asociada es baja.