Evaluación de la utilidad del coeficiente de difusión aparente en resonancia magnética para la diferenciación del grado tumoral de los tumores cerebrales pediátricos / Evaluating the apparent diffusion coefficient in MRI studies as a means of determining paediatric brain tumour stages

Introducción: El coeficiente de difusión aparente (ADC) de la resonancia magnética parece relacionarse con el grado de celularidad de los tumores de sistema nervioso central. Su utilidad para diferenciar el grado tumoral y tipo histológico de los tumores es controvertido. Material y métodos: Estudio retrospectivo de los pacientes pediátricos con diagnóstico de tumor de sistema nervioso central desde enero-2008 a diciembre-2013. Se revisan edad, sexo, localización del tumor y anatomía patológica. Las medidas de ADC y ratio ADC (cociente ADC tumoral/ADC tejido sano) se llevaron a cabo por 2 neurorradiólogos expertos, ciegos al diagnóstico histológico. Se calcula el valor ADC y el ratio ADC y se comparan sus valores con los diagnósticos anatomopatológicos. Resultados: Se incluyen 55 pacientes. La mediana de edad fue 6 años. Los diagnósticos anatomopatológicos fueron: astrocitoma pilocítico (40%), ependimoma anaplásico (16,4%), ganglioglioma (10,9%), glioblastoma (7,3%), meduloblastoma (5,5%), y otros (20%). El 64% fueron de bajo grado (BG) y el 36% de alto grado (AG). La media de ADC fue 1,3 en los de BG y 0,9 en los de AG (p = 0,004). La media de ratio ADC fue de 1,5 y 1,2 (p = 0,025) respectivamente. No hubo diferencias significativas en el ADC/ratio ADC entre los distintos tipos histológicos. Conclusiones: El ADC y ratio ADC son una herramienta útil en la diferenciación por imagen del grado tumoral en los tumores cerebrales pediátricos, sin sustituir a la anatomía patológica

Background: The apparent diffusion coefficient (ADC) in MRI seems to be related to cellularity in brain tumours. Its utility as a tool for distinguishing between histological types and tumour stages remains controversial. Procedures: We retrospectively evaluated children diagnosed with CNS tumours between January 2008 and December 2013. Data collected were age, sex, histological diagnosis, and location of the tumour. We evaluated the ADC and ADC ratio and correlated those values with histological diagnoses. Results: The study included 55 patients with a median age of 6 years. Histological diagnoses were pilocytic astrocytoma (40%), anaplastic ependymoma (16.4%), ganglioglioma (10.9%), glioblastoma (7.3%), medulloblastoma (5.5%), and other (20%). Tumours could also be classified as low-grade (64%) or high-grade (36%). Mean ADC was 1.3 for low-grade tumours and 0.9 for high-grade tumours (p = .004). Mean ADC ratios were 1.5 and 1.2 for low and high-grade tumours respectively (p = .025). There were no significant differences in ADC/ADC ratio between different histological types. Conclusion: ADC and ADC ratio may be useful in imaging-study based differential diagnosis of low and high-grade tumours, but they are not a substitute for an anatomical pathology study

Evaluating the apparent diffusion coefficient in MRI studies as a means of determining paediatric brain tumour stages. / Evaluación de la utilidad del coeficiente de difusión aparente en resonancia magnética para la diferenciación del grado tumoral de los tumores cerebrales pediátricos.

BACKGROUND: The apparent diffusion coefficient (ADC) in MRI seems to be related to cellularity in brain tumours. Its utility as a tool for distinguishing between histological types and tumour stages remains controversial. PROCEDURES: We retrospectively evaluated children diagnosed with CNS tumours between January 2008 and December 2013. Data collected were age, sex, histological diagnosis, and location of the tumour. We evaluated the ADC and ADC ratio and correlated those values with histological diagnoses. RESULTS: The study included 55 patients with a median age of 6 years. Histological diagnoses were pilocytic astrocytoma (40%), anaplastic ependymoma (16.4%), ganglioglioma (10.9%), glioblastoma (7.3%), medulloblastoma (5.5%), and other (20%). Tumours could also be classified as low-grade (64%) or high-grade (36%). Mean ADC was 1.3 for low-grade tumours and 0.9 for high-grade tumours (p=.004). Mean ADC ratios were 1.5 and 1.2 for low and high-grade tumours respectively (p=.025). There were no significant differences in ADC/ADC ratio between different histological types. CONCLUSION: ADC and ADC ratio may be useful in imaging-study based differential diagnosis of low and high-grade tumours, but they are not a substitute for an anatomical pathology study.

[Initial signs and symptoms of brain tumors in children]. / Síntomas y signos iniciales de los tumores cerebrales pediátricos.

INTRODUCTION: This is a study of the presenting features of brain tumors in children, their localization and histology which is aimed at describing the most frequent symptoms at the beginning and at the moment of diagnosis and minimize the time needed to reach a diagnosis. METHODS: Retrospective and descriptive study. Data were collected from the medical records of the patients (aged: 0-16) operated on for a brain tumor in our Department from 1999 to 2004. All analyses were conducted with the SPSS 11.0. RESULTS: In our study, the prevalence of brain tumors was higher in males (58%) older than five years. Of these, 52% were supratentorial and the most frequent one was astrocytome. Median time to diagnosis was 30 days. A total of 75% were diagnosed during the first 60 days of the onset of the symptoms. We found a statistically significant relationship between age and mean time to d i a gnosis. The most frequent initial symptom was increased head circumference and nausea/vomiting in children younger than 2 years, vomiting and headache in children aged 2-5, and headache in older than 5 years. In all groups, 83% of headache was accompanied by vomiting. CONCLUSIONS: Mean time to diagnosis in our study is similar to other series. Presenting features vary based on age and they are not pathognomonic of the brain tumors. This hinders early diagnosis. In order to make an early diagnosis, it is important to pay attention to the associated symptoms and chronology.

Síntomas y signos iniciales de los tumores cerebrales pediátricos / Initial signs and symptoms of brain tumors in children

tumores cerebrales en niños, sus características histológicasy su localización con el fin de conocer los síntomasmás habituales al inicio y en el momento del diagnóstico eintentar disminuir el tiempo hasta éste.Métodos. Estudio retrospectivo, descriptivo. Informaciónrecogida de las historias clínicas de 50 pacientes pediátricosintervenidos en nuestro centro de tumor cerebral primarioentre 1999 y 2004 analizada con SPSS 11.0.Resultados. En nuestra serie los tumores cerebralesfueron más prevalentes en niños (58%) mayores de 5 años,un 52% era supratentorial y el astrocitoma fue el más frecuente.La mediana de tiempo al diagnóstico fue de 30 díasy el 75% se diagnosticaron en los 60 días siguientes a la primeraconsulta. Encontramos una relación estadísticamentesignificativa entre el tiempo transcurrido hasta el diagnósticoy la edad. La clínica más frecuente en el diagnóstico eraaumento del perímetro craneal y náuseas/vómitos en losmenores de 2 años, náuseas/vómitos y cefalea en los niñosde 2 a 5 años y cefalea en los mayores de 5 años. En todoslos grupos el 83% de las cefaleas se acompañaban de náuseas/vómitos.Conclusiones. El tiempo medio hasta el diagnóstico ennuestra serie es aceptable comparado con otras. La clínicavaría en función de la edad y no es patognomónica de lostumores cerebrales, lo que dificulta el diagnóstico precoz.Para un diagnóstico precoz es importante fijarse en la asociaciónde síntomas y en la cronología (AU)

Introduction. This is a study of the presenting featuresof brain tumors in children, their localization andhistology which is aimed at describing the most frequentsymptoms at the beginning and at the moment of diagnosisand minimize the time needed to reach a diagnosis.Methods. Retrospective and descriptive study. Datawere collected from the medical records of the patients(aged: 0-16) operated on for a brain tumor in our Departmentfrom 1999 to 2004. All analyses were conductedwith the SPSS 11.0.Results. In our study, the prevalence of brain tumorswas higher in males (58%) older than five years. Of these,52% were supratentorial and the most frequent onewas astrocytome. Median time to diagnosis was 30 days.A total of 75% were diagnosed during the first 60 daysof the onset of the symptoms. We found a statisticallysignificant relationship between age and mean time to diagnosis.The most frequent initial symptom was increasedhead circumference and nausea/vomiting in childrenyounger than 2 years, vomiting and headache in childrenaged 2-5, and headache in older than 5 years. In allgroups, 83% of headache was accompanied by vomiting.Conclusions. Mean time to diagnosis in our study issimilar to other series. Presenting features vary based onage and they are not pathognomonic of the brain tumors.This hinders early diagnosis. In order to make anearly diagnosis, it is important to pay attention to theassociated syntoms and chronology (AU)