TLR Agonists Modify NK Cell Activation and Increase Its Cytotoxicity in Acute Lymphoblastic Leukemia.

Natural killer (NK) cells play a crucial role in innate immunity, particularly in combating infections and tumors. However, in hematological cancers, NK cells often exhibit impaired functions. Therefore, it is very important to activate its endosomal Toll-like receptors (TLRs) as a potential strategy to restore its antitumor activity. We stimulated NK cells from the peripheral blood mononuclear cells from children with acute lymphoblastic leukemia and NK cells isolated, and the NK cells were stimulated with specific TLR ligands (Poly I:C, Imiquimod, R848, and ODN2006) and we evaluated changes in IFN-γ, CD107a, NKG2D, NKp44 expression, Granzyme B secretion, cytokine/chemokine release, and cytotoxic activity. Results revealed that Poly I:C and Imiquimod enhanced the activation of both immunoregulatory and cytotoxic NK cells, increasing IFN-γ, CD107a, NKG2D, and NKp44 expression. R848 activated immunoregulatory NK cells, while ODN2006 boosted CD107a, NKp44, NKG2D, and IFN-γ secretion in cytotoxic NK cells. R848 also increased the secretion of seven cytokines/chemokines. Importantly, R848 and ODN 2006 significantly improved cytotoxicity against leukemic cells. Overall, TLR stimulation enhances NK cell activation, suggesting TLR8 (R848) and TLR9 (ODN 2006) ligands as promising candidates for antitumor immunotherapy.

Epidemiology of childhood acute leukemias in marginalized populations of the central-south region of Mexico: results from a population-based registry.

Introduction: Acute leukemias (AL) are the main types of cancer in children worldwide. In Mexico, they represent one of the main causes of death in children under 20 years of age. Most of the studies on the incidence of AL in Mexico have been developed in the urban context of Greater Mexico City and no previous studies have been conducted in the central-south of the country through a population-based study. The aim of the present work was to identify the general and specific incidence rates of pediatric AL in three states of the south-central region of Mexico considered as some of the marginalized populations of Mexico (Puebla, Tlaxcala, and Oaxaca). Methods: A population-based study was conducted. Children aged less than 20 years, resident in these states, and newly diagnosed with AL in public/private hospitals during the period 2021-2022 were identified. Crude incidence rates (cIR), standardized incidence rates (ASIRw), and incidence rates by state subregions (ASIRsr) were calculated. Rates were calculated using the direct and indirect method and reported per million children under 20 years of age. In addition, specific rates were calculated by age group, sex, leukemia subtype, and immunophenotype. Results: A total of 388 cases with AL were registered. In the three states, the ASIRw for AL was 51.5 cases per million (0-14 years); in Puebla, it was 53.2, Tlaxcala 54.7, and Oaxaca de 47.7. In the age group between 0-19 years, the ASIRw were 44.3, 46.4, 48.2, and 49.6, in Puebla, Tlaxcala, and Oaxaca, respectively. B-cell acute lymphoblastic leukemia was the most common subtype across the three states. Conclusion: The incidence of childhood AL in the central-south region of Mexico is within the range of rates reported in other populations of Latin American origin. Two incidence peaks were identified for lymphoblastic and myeloid leukemias. In addition, differences in the incidence of the disease were observed among state subregions which could be attributed to social factors linked to the ethnic origin of the inhabitants. Nonetheless, this hypothesis requires further investigation.

Evidence of spatial clustering of childhood acute lymphoblastic leukemia cases in Greater Mexico City: report from the Mexican Inter-Institutional Group for the identification of the causes of childhood leukemia.

Background: A heterogeneous geographic distribution of childhood acute lymphoblastic leukemia (ALL) cases has been described, possibly, related to the presence of different environmental factors. The aim of the present study was to explore the geographical distribution of childhood ALL cases in Greater Mexico City (GMC). Methods: A population-based case-control study was conducted. Children <18 years old, newly diagnosed with ALL and residents of GMC were included. Controls were patients without leukemia recruited from second-level public hospitals, frequency-matched by sex, age, and health institution with the cases. The residence address where the patients lived during the last year before diagnosis (cases) or the interview (controls) was used for geolocation. Kulldorff's spatial scan statistic was used to detect spatial clusters (SCs). Relative risks (RR), associated p-value and number of cases included for each cluster were obtained. Results: A total of 1054 cases with ALL were analyzed. Of these, 408 (38.7%) were distributed across eight SCs detected. A relative risk of 1.61 (p<0.0001) was observed for the main cluster. Similar results were noted for the remaining seven ones. Additionally, a proximity between SCs, electrical installations and petrochemical facilities was observed. Conclusions: The identification of SCs in certain regions of GMC suggest the possible role of environmental factors in the etiology of childhood ALL.

Maternal diet in pregnancy and acute leukemia in infants: a case-control study in Mexico City.

Introduction: Epidemiological studies around the world on acute leukemia (AL) and risk factors in infants are scarce. Infant AL has been proposed to originate in utero, which facilitates its study by establishing a short exposure time in pregnant women to environmental and dietary factors that could contribute to the risk of or protection against leukemia. We hypothesized that maternal diet during pregnancy may be an important factor involved in AL in offspring. Methods: We conducted a hospital-based case-control study from 2010 to 2019 on maternal diet during pregnancy in nine high-specialty public hospitals of different health institutions that diagnose and offer treatment to children with AL in Mexico City. Cases (n=109) were children ≤24 months of age with de novo diagnosis of AL, and controls (n=252) were children obtained in hospitals from second-level medical care matched for age, sex, and health institution. Maternal diet during pregnancy was obtained by a semiquantitative food frequency questionnaire. Unconditional logistic regression models were used to assess the association between food groups and infant AL. Potential confounders were assessed by constructing directed acyclic graphs (DAGs) with Dagitty software in which adjusted options were identified for the construction of unconditional logistic regression models. Results: Cases were slightly predominantly female (52.3%). The years of education of the mother in cases and controls was 0-9 on average, and those who reported smoking cigarettes and consuming alcohol during pregnancy did so at a low frequency. Regarding the mother's diet, the main findings were that the consumption of allium vegetables during pregnancy was inversely associated with AL for medium and high consumption (OR=0.26, 95% CI 0.14-0.46; P-trend< 0.001). In contrast, the high consumption of high-fat dairy products had a positive association with AL (OR=2.37, 95% CI 1.30-4.34; P-trend<0.001). No association was found between consumption of topoisomerase II inhibitor foods during pregnancy and AL. Conclusion: The results suggest that maternal intake during pregnancy of allium vegetables, specifically garlic, is inversely associated with the development of AL in children ≤24 months old. On the other hand, consumption of high-fat dairy products is positively associated with AL in children ≤24 months old.

Identificación de Microsporidium spp en pacientes con diagnóstico de leucemia linfoblástica aguda / Identification of Microsporidium spp in patients with acute lymphoblastic leukemia

Introducción. El grupo Microsporidia incluye parásitos intracelulares obligados que afectan varios huéspedes. Los géneros que infectan humanos son Enterocytozoon y Encephalitozoon . Microsporidia es considerado un organismo oportunista en pacientes inmunocomprometidos e inmunocompetentes, que se ha convertido en un importante problema de salud pública. El objetivo del trabajo fue identificar Microsporidium spp en muestras fecales de pacientes con leucemia linfoblástica aguda, en diferente etapa de su tratamiento. Métodos. Se analizaron 77 muestras de niños con diagnóstico de leucemia linfoblástica aguda menores de 12 años, por análisis coproparasitoscópico de Faust. Las muestras se tiñeron con Ziehl Nielsen, tricrómica de Masson y calcoflúor. Finalmente se realizó la amplificación por PCR del gen ribosomal. Resultados. De los pacientes analizados, 16/77 (20.77%) resultaron positivos para Microsporidia, independientemente de que presentaran diarrea. El PCR fue más efectivo para la identificación que el análisis microscópico de las muestras teñidas. Conclusiones. Este trabajo enfatiza la importancia de la microsporidiosis como infección emergente en pacientes con leucemia linfoblástica aguda bajo tratamiento quimioterapéutico, incrementando las complicaciones clínicas adicionales a la leucemia.

Background. The phylum Microsporidia includes obligate intracellular parasites that affect several hosts. The most frequent genera to affect humans are Enterocytozoon and Encephalitozoon. Microsporidium is considered an opportunistic parasite in both immunocompromised and immunocompetent patients and have become an important health problem. The aim of this study was to identify Microsporidium spp in fecal samples of patients with acute lymphoblastic leukemia (ALL), with and without diarrhea, at different treatment stages. Methods. Seventy seven samples from children <12 years old with diagnosis of ALL were analyzed by the Faust coproparasitoscopic method, Ziehl-Nielsen, trichrome and calcofluor staining methods and polymerase chain reaction. Results. Results showed that 16/77 (20.77%) children presented Microsporidium and there was no relationship between microsporidial infection and diarrhea. Polymerase chain reaction was more effective than analysis by light microscopy of staining samples in the identification of the parasite. Conclusions. This work emphasizes the importance of microsporidiosis as an emerging infection in patients with ALL undergoing chemotherapy, increasing the additional clinical complications of leukemia.

Comparación de las características clínicas al diagnóstico de niños con leucemia linfoblástica aguda afiliados al Seguro Popular, con respecto al desenlace / Comparison, in relation to outcome, of the clinical characteristics at diagnosis of children with acute lymphoblastic leukemia affiliated with the Seguro Popular insurance program

Introducción. La leucemia linfoblástica aguda es el tipo de cáncer infantil más frecuente. Los pacientes son clasificados de acuerdo con los hallazgos clínicos, biológicos, moleculares y de respuesta a la terapia inicial. Este trabajo tuvo como objetivo caracterizar los hallazgos al diagnóstico de una muestra de pacientes mexicanos e identificar las diferencias clínicas de acuerdo con la mortalidad cruda. Métodos. Se revisaron 391 expedientes de pacientes pediátricos con leucemia linfoblástica aguda en nueve hospitales afiliados al Seguro Popular en la República Mexicana. Resultados. Se incluyeron 296 pacientes vivos y 95 fallecidos. La media de edad fue de 6.48 años en los vivos y 8.31 años en los fallecidos. Los signos y síntomas para solicitar la atención médica fueron fiebre, palidez, astenia y adinamia. Las principales alteraciones hematológicas fueron anemia y trombocitopenia. La mayor proporción de blastos en sangre periférica se observó en el grupo de los fallecidos (28.3 vs 40.7, p=0.030). El 86.4% de la muestra contaba con inmunofenotipo y 11.2% tenía estudio citogenético. En cuanto al riesgo, 148 pacientes se clasificaron como de riesgo habitual y 230 como de alto riesgo. Conclusiones. Caracterizar la población de niños con leucemia linfoblástica aguda permite a los sistemas de salud conocer sus peculiaridades e implementar acciones específicas para mejorar la atención, como el desarrollo de estrategias para realizar los inmunofenotipos y la citogenética.

Background. Acute lymphoblastic leukemia (ALL) is the most common cancer in childhood. Patients are classified according to clinical, biological, and molecular characteristics as well as their response to initial therapy. The objective of this study is aimed to characterize the diagnostic findings in a sample of Mexican patients with ALL and to identify clinical differences according to crude mortality. Methods. We reviewed clinical records of 391 pediatric ALL patients in nine hospitals in Mexico affiliated with the Seguro Popular insurance program. Results. Included in this study were 296 living patients and 95 deceased patients. Mean age was 6.48 years and 8.31 years for living and deceased patients, respectively. Signs and symptoms associated with seeking medical care were fever, pallor, fatigue and weakness. The main hematologic abnormalities were anemia and thrombocytopenia. The largest proportion of blasts in peripheral blood was observed in the group of deceased patients; 86.4% of the sample had immunophenotype in the clinical record and only 11.2% had cytogenetic study. One hundred forty eight patients were classified as standard risk and 230 patients as high risk. Conclusions. To characterize the population of children with ALL allows health systems to be aware of the features of patients with ALL and to implement specific actions and to develop strategies so that all patients have access to immunophenotype and cytogenetic studies.

Calidad de vida en niños con leucemia linfoblástica aguda durante la inducción a la remisión mediante el PedsQL Cancer Module© / Quality of life in children with acute lymphoblastic leukemia during induction therapy with PedsQL Cancer Module©

Introducción. Con los tratamientos disponibles en la actualidad, más de 80% de los niños con leucemia aguda linfoblástica (LAL) pueden sobrevivir. En general, y específicamente en nuestra institución, no se conoce bien la calidad de vida (CV) de estos niños. El objetivo de este estudio fue medir la CV en niños durante la inducción a la remisión (primera fase del tratamiento) con el PedsQL Cancer Module©. Métodos. Se realizaron 2 mediciones a niños con LAL de diagnóstico reciente. Se incluyeron 26 pacientes estables de 2 a 18 años de edad con LAL, a las 2 semanas y a los 2 meses del diagnóstico. Se dividieron en 4 grupos: 2-4, 5-7, 8-12 y 13-18 años. Resultados. Se determinó que la CV se modificó al finalizar la inducción a la remisión. En la segunda medición se observó mejor CV con relación a un proceso de posible adaptación al tratamiento, así como por mejoría de los síntomas relacionados a la enfermedad. Conclusión. El PedsQL Cancer Module© fue útil para medir la CV y detectar cambios en los niños con LAL en inducción a la remisión.

Introduction. Survival of children with acute lymphoblastic leukemia (ALL) is 80% in accordance with actual protocols. We ignore quality of life (QoL) during these chronic treatments, especially in our institution. The aim of this pilot study was to measure QoL in stable children with ALL during the first part of treatment (induction therapy) with PedsQL Cancer Module©. Methods. We made two measurements in children with recent diagnosis of ALL and determined changes in the QoL between the beginning and the end of induction therapy. We included 26 patients from 2 to 18 years of age with ALL, at 2 weeks and 2 months after diagnosis, and divided them into four groups: 2-4, 5-7, 8-12, and 13-18 years of age. Results. In the second measurement, we observed a better QoL in relation to an adaptation process in the child and remission of symptoms. Conclusions. PedsQL Cancer Module© was a useful instrument for measuring QoL and detected changes in children with ALL during induction therapy.

Parámetros de práctica para el manejo del dolor en cáncer: Grupo de Consenso para el Manejo del Dolor en Cáncer / Practice guidelines for cancer pain management: Task Force for Cancer Pain Management

El dolor por cáncer es un problema frecuente en nuestro medio, se presenta en 80 a 90 % de los pacientes y en aproximadamente 90 % de ellos se resuelve con medidas relativamente sencillas. No obstante, aproximadamente 40 % de los pacientes se encuentra insatisfecho con el médico o la enfermera respecto al manejo de su dolor. Por tal motivo, se convocó a un grupo de consenso con la finalidad de generar parámetros de práctica clínica fundamentados en la evidencia publicada y en la opinión de los expertos. Este grupo estuvo integrado por 31 médicos líderes de opinión es este campo, quienes con base en 599 documentos emitieron esta serie de recomendaciones, identificadas cada una según su nivel de evidencia.

Cancer pain is a frequent medical problem in our society. This syndrome affects from 80 to 90% of cancer patients and can be solved with relatively simple measures in 90% of the cases. Approximately 40% of cancer patients reported to be unsatisfied with the physician or nurse about their pain management. For these reasons, we gathered a task force in order to generate practice guidelines based on medical evidence and on the opinion of experts in this area. These guidelines were generated by a task force of 31 physicians who were leaders in this field and based on 599 papers selected by a previous literature search. This group evaluated the results of this search in three work sessions, during which a level of evidence was assigned to each recommendation.

Quimioterapia neoadyuvane en pacientes pediátricos con hepatoblastoma: experiencia del Hospital Infantil de México Federico Gómez / Neoadyuvante chemotherapy in children with hepatoblastoma: the Hospital Infantil de Mexico experiences

Introducción. El hepatoblastoma (HB) es la neoplasia maligna de hígado más frecuente en pediatría. Antes de la década de los noventas, la sobrevida de los pacientes con HB era inferior al 25 por ciento. La introducción de quimioterapia neoadyuvante (QTN) en el tratamiento del HB ha facilitado su manejo quirúrgico, disminuyendo la mortalidad perioperatoria e incrementando la sobrevida a más de 70 por ciento. Material y métodos. Siete pacientes con diagnóstico histológico de HB fueron incluidos en el estudio para evaluar el papel de la QTN como parte esencial del tratamiento y valorar la utilidad de la alfafetoproteína (AFP) y colesterol como indicadores de respuesta, al correlacionarlos con la respuesta clínica, tomográfica e histopatológica. Se administraron 4 ciclos de QTN con cisplatino, 5 fluoracilo y vincristina, seguidos de resección quirúrgica del tumor primario y 2 ciclos de quimioterapia posterior a ésta. Resultados. Se obtuvo respuesta en todos los casos. La resección completa fue posible en 5. En 2 pacientes con grandes tumores sólo hubo respuesta parcial, siendo necesario modificar el esquema de tratamiento; la mala respuesta se correlacionó con niveles séricos persistentemente elevados de AFP y colesterol. Conclusión. La QTN demostró ser el tratamiento de elección para los tumores primarios de hígado, ya que permite obtener resecciones completas en tumores inicialmente irresecables, controlar metástasis y evaluar quimiosensibilidad. El colesterol se relacionó con la respuesta obtenida a QTN. Hepatoblastoma; quimioterapia neoadyuvante; indicadores de respuesta.

Osteosarcoma como segunda neoplasia de retinoblastoma / Osteosarcoma as a second neoplasm in a children with retinoblastoma

Introducción. Es bien conocido que el osteosarcoma se presenta frecuentemente como segunda neoplasia del retinoblastoma congénito, así como otro tipo de carcinomas, melanomas y tumores neuroepiteliales. Todos los pacientes con retinoblastoma bilateral congéntio presentan una alteración del gen RB1 localizado en el cromosoma 13q14. Caso clínico. Se presenta el caso de una paciente con retinoblastoma bilateral congénito diagnosticado a la edad de 1 año 11 meses, quien recibió tratamiento con ciclofosfamida, epirrubicina y VP 16, entre otros agentes; y que desarrolló osteosarcoma peroneo con metástasis pulmonares tras una latencia de 10 años 6 meses. En esta paciente es conocido el uso de alquilantes, antracíclicos y etopósido, así como los antecedentes familiares de cáncer por ambas ramas. Conclusión. El retinoblastoma bilateral conlleva factores de riesgo para el desarrollo de segundas neoplasias. Los antecedentes familiares constituyen razones suficientes para catalogarlo como un síndrome de cáncer familiar, el uso de agentes alquilantes, antraciclicos y etopósidos, aumentan este riesgo acortando el período de latencia

Ciclofosfamida a dosis escaladas en tumores sólidos malignos en población pediátrica: Experiencia en el Hospital Infantil de México Federico Gómez / Cyclophosphamide dose escalation in solid tumors in children

Introducción. La ciclofosfamida a dosis escaladas incrementó su citotoxicidad en tumores sensibles a ésta, sin aumento de sus efectos tóxicos. Material y métodos. Se evaluaron 50 pacientes con tumores sólidos, en los que se utilizó ciclofosfamida en dosis escaladas de 2.5 g hasta 4.5 g/m² de superficie corporal como esquema de primera línea o de rescate, con uroprotector y factor estimulante de colonia en cada ciclo. La toxicidad y la respuesta fueron basadas en criterios de la Organización Mundial de la Salud. Resultados. Los diagnósticos más frecuentes fueron tumores del sistema nervioso central y retinoblastoma con 18 y 9 pacientes respectivamente. Cuarenta y cinco pacientes (90 por ciento) presentaron respuesta a quimioterapia, ya sea completa (72 por ciento) o parcial. Sólo en 5 pacientes no hubo respuesta. Se presentaron 3 episodios de cistitis hemorrágica. Conclusiones. Se comprobó que la ciclofosfamida a dosis escalada es activa en un grupo heterogéneo de pacientes con tumores sólidos y que esta modalidad terapéutica no incrementa el riesgo de toxicidad