Objectives: To determine overall survival (OS) and event-free (EFS) in children with rhabdomyosarcoma treated at the NCI. Methods: We reviewed the medical records of patients with rhabdomyosarcoma treated at pediatric oncology clinic INC between January 2002 and December 2009. We performed descriptive analysis of sociodemographic and clinical characteristics of patients; we calculated the survival function by Kaplan-Meier method. Results: We included 45 cases, 25 males, 30 were from rural area, the median age was 10 years (0-18). 31.1% of patients were classified as high risk, 42.2% intermediate and 20% low. The mean follow-up was 2.38 years (SD = 2.51). There were 28 events, the cumulative probability of survival was 21.9%. Of all patients 37.8% died, the cumulative probability of OS was 50.3%. There was no significant association between variables and survival analysis. Conclusions: The survival of our patients is comparable with other studies in developing countries, but away from the results of studies in European countries and the USA. Our patients present with advanced stage and poor prognostic factors. Keywords: Rabdomyosarcoma, neoplasm, children, survival

La transición epitelio-mesénquima (TEM) es la capacidad de las células epiteliales y mesenquimales de intercambiar de fenotipo de forma transitoria; su identificación en células tumorales carcinomatosas se ha asociado con fenotipos clínicos agresivos. En sarcomas, este evento biológico se encuentra en estudio. Objetivo: evaluar la expresión de dos factores de transcripción involucrados en la TEM mediante inmunohistoquímica en osteosarcoma en pacientes pediátricos y su asociación con desenlaces clínicos. Pacientes y Método: Estudio retrospectivo en menores de 18 años con diagnóstico de osteosarcoma. Se realizó inmunohistoquímica para Snail y Twist-1 en muestras obtenidas al momento del diagnóstico. Posteriormente fue explorada la correlación entre la positividad de los marcadores con los desenlaces clínicas y con la supervivencia global. Resultados: 53 pacientes fueron incluidos. Para Snail, se encontró positivo en localización citoplasmático en 26 casos (49,1...

Resumen Objetivo Analizar características por resonancia magnética (RM) de gliomas IDH-mutados (grado II y III) en base a parámetros cualitativos, a fin de valorar el rendimiento del signo del mismatch T2-FLAIR y otras características morfológicas de los tumores, en predecir el estado del 1p/19q y su reproducibilidad interobservador. Métodos Estudio retrospectivo, descriptivo y analítico sobre una cohorte de 53 gliomas IDH-mutados (grado II y III) y molecularmente definidos respecto al 1p/19q, seleccionados a partir de la base de datos de la institución, durante el periodo 2014–2019. Dos neuroradiólogos evaluaron características imagenológicas de forma independiente y enmascarada al diagnóstico: mismatch T2-FLAIR, localización tumoral, bordes, señal, infiltración cortical e inhomogeneidad en T2*. Los casos discordantes fueron evaluados por un tercer neuroradiólogo de mayor experiencia. Resultados Treinta de 53 (56,6%) gliomas fueron no codelecionados, y 23/53 (43,4%) codelecionados....

In order to define the molecular and cellular bases of the development of retinoblastomas it is necessary to know its etiology, and to apply the advances in genome technology to this kind of neoplasia. Retinoblastomas are childhood tumors of the eye with an average incidence of one case in every 15,000-20,000 live births, which occur in sporadic and hereditary forms. The sporadic form appears regularly as a unilateral tumor, while in the familial form of the disease, tumors may be unilateral and bilateral. This neoplasia is characterized by leukocoria, strabism, and heterochromia. The retinoblastoma gene (RB1) is a molecular marker of retinoblastoma tumors. This gene is located in chromosome 13q14.2 and encodes a nuclear phosphoprotein (pRB) of 110 KDa, which plays a major role in cell proliferation control through cell cycle-regulated phosphorylation/dephosphorylation cycles of this protein. The RB1 gene is mainly affected by point mutations, which occur most frequently in exons 3,...

Classic Hodgkin lymphoma (cHL) in young children (ages 0–6) is rare in high income countries (HICs) but is more prevalent in low- and middle-income countries (LMICs) like Guatemala. Given that the majority of cHL studies have evaluated adolescent/adults, and the immune system changes with age, we sought to characterize Epstein-Barr virus (EBV) expression, immune regulatory pathway markers and the tumor microenvironment in 42 children ages 0–6 with cHL from Guatemala. We found a very high frequency of EBV expression (97.5%). Hodgkin cells showed increased expression of PD1 ligands and CD137, indicative of shared immune regulatory mechanisms with adult cHL. Pediatric cHL also showed an increase in CD8+ tumor infiltrating lymphocytes and tumor associated macrophages within the tumor microenvironment. Despite 25 having high risk disease, only 4 patients died from progressive disease, relapse or infection.