Biomarcadores radiológicos en RM para una aproximación al diagnóstico molecular en gliomas IDH-mutados (grado II y III) / MR Imaging Biomarkers for a Diagnostic Approach of IDH-mutated Gliomas (Grades II/III)

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. El signo del mismatch T2-FLAIR fue positivo en 16/53 (30,18%) pacientes, 15/16 (93,75%) no codelecionados y 1/16 (6,25%) codelecionado (Exacto de Fisher p = <,0001). Los dos evaluadores demostraron una concordancia interobservador casi perfecta para ese signo, κ =,907 (95% CI, 0,781 a 1,0). La especificidad y el valor predictivo positivo del signo para predecir la ausencia de la codeleción fue de un 95,7% y un 93,8% respectivamente. Discusión: La reciente actualización en la clasificación de los gliomas los clasifica acorde a su perfil molecular. En los últimos años, varios investigadores han estudiado características morfológicas por RM de los tumores con la intención de predecir las características moleculares de los mismos. Conclusión: En nuestra población, el signo del mismatch T2-FLAIR es el único biomarcador radiológico que muestra asociación estadísticamente significativa en predecir la ausencia de codeleción en los gliomas IDH-mutados (grado II y III), con una alta especificidad y un alto valor predictivo positivo.

Abstract Objective: To analyze magnetic resonance (MR) characteristics of IDH-mutated gliomas (grades II/III) utilizing qualitative parameters with the goal of assessing the performance of the T2-FLAIR mismatch sign and other morphological characteristics of tumors in predicting the 1p/19q co-deletion status as well as inter-observer reproducibility. Methods: Retrospective and descriptive study analyzing a cohort of 53 IDH-mutated lower-grade (grades II/III) gliomas with known 1p/19q co-deletion status. Patients meeting selection criteria for this study were taken from our institutional data from 2014-2019. Two neuroradiologists assessed the following imaging characteristics independently, and blinded from the diagnosis: T2-FLAIR mismatch, tumor location, borders, signal characteristics, cortical infiltration and T2* inhomogeneity. In the event of discordant interpretations, a third senior neuroradiologist also evaluated the case. Results: 23 of the 53 (43.4%) gliomas demonstrated 1p/19q co-deletion and 30 of 53 (56.6%) did not. T2-FLAIR mismatch was positive in 16 of 53 cases (30.2%) with 15 of 16 (93.8%) demonstrating no co-deletion and 1/16 (6.25%) with co-deletion (Fisher's exact p = < .0001). The two readers showed an almost perfect interreader agreement for this sign κ = 0.907 (95% CI, 0.781 to 1.0). Specificity and positive predictive value of the sign to predict the absence of co-deletion was 95.7% and 93.8% respectively. Discussion: The recent update in classification of lower-grade gliomas segregates gliomas according to molecular profile. In the recent past, many researchers have studied MR morphologic characteristics of these tumors with the intention of predicting molecular features of said tumors Conclusion: In our patient population, T2-FLAIR mismatch sign is the only radiologic biomarker that shows statistically significant association with the absence of 1p/19q co-deletion in lower-grade gliomas, with high specificity and positive predictive value.

Pilocytic astrocytoma, another way to reach your diagnosis / Astrocitoma pilocítico, outra forma de chegar ao seu diagnóstico

Abstract Cerebellar astrocytoma (low-grade glioma) is the most frequent tumor of the Central Nervous System in pediatric age, corresponding to 10-20% of brain tumors, having its maximum incidence at 5 years. Brain tumors are the second cause of death at this age, behind leukemias. Its most frequent clinic is headache with vomiting which can worsen in the morning and awaken the patient at night. The most frequent ophthalmological clinic is papilledema and involvement of the cranial nerve VI. In our case we present an atypical presentation (cranial IV), in which a quick derivation favored a better prognosis.

Resumo O astrocitoma cerebelar (glioma de baixo grau) é o tumor mais frequente do Sistema Nervoso Central em idade pediátrica, correspondendo a 10-20% dos tumores cerebrais, tendo sua incidência máxima em 5 anos. Os tumores cerebrais são a segunda causa de morte nesta idade, atrás das leucemias. Sua clínica mais frequente é a cefaleia com vômitos que podem piorar pela manhã e despertar o paciente à noite. A clínica oftalmológica mais frequente é o papiledema e o envolvimento do nervo craniano VI. Em nosso caso apresentamos uma apresentação atípica (IV craniana), em que uma derivação rápida favoreceu um melhor prognóstico.

Spinal pleomorphic xanthoastrocytoma: case report and literature review / Xantoastrocitoma pleomórfico espinal: reporte de caso y revisión de la literatura

El Xantoastrocitoma Pleomórfico Espinal (XAPE) es una neoplasia primaria infrecuente del sistema nervioso central, descrita por primer vez en 1979. De estirpe astrocítica y aunque clasificada como grado II por la OMS, pueden existir variantes anaplásicas o malignas. Con localización usualmente temporal, pocos casos espinales se han descrito a la fecha, debido probablemente a un subdiagnóstico o un subregistro. El pronóstico es generalmente bueno y depende en gran medida del tipo histológico y extensión de la resección quirurgica. Describimos el caso de un hombre de 30 años de edad con dorsalgiay paresia del miembro inferior izquierdo. Se encontró en imágenes de resonancia magnética una lesión aparentemente intradural, extraaxial en los segmentos T8-T9 que se llevó a resección. Se confirmó por histopatología la presencia de un XAPE primario. En la presente publicación realizamos una revisión de la literatura disponible.

Spinal Pleomorphic Xanthoastrocytoma (SPXA) is a rare CNS primary neoplasm, first described in 1979. Although of astrocytic lineage and classified as a grade II neoplasm by the WHO, it may be have anaplastic or malignant variants. Usually located in the temporal lobe, few spinal cases have been described to date, probably due to underdiagnosis and underreporting. It usually has a good prognosis, but it depends on its histological type and extent of surgical resection. In this article, we describe the case of a 30-year old male who complained of low back pain and left lower limb paresis. The MRI showed an apparently intradural, extraaxial lesion at T8-T9 segments. The diagnosis of a primary SPXA was confirmed by histopathological studies. In this article, a review of the available literature is presented.

Relationship Between Cytogenetic Complexity and Peritumoral Edema in High-Grade Astrocytoma

BACKGROUND: The purpose of the study is to reveal the association of cytogenetic compltyexi and peritumoral edema volume (PTEV) and its prognostic significance in high-grade astrocytoma patients by culturing patient tumor cells. METHODS: Twenty-seven high-grade astrocytoma patients were divided into three groups according to karyotype complexity: normal, non-complex karyotype (NCK), and complex karyotype (CK). Endothelial growth factor receptor (EGFR) amplification was detected by FISH, and its association with chromosome 7 abnormalities was analyzed. Mean PTEV of each group was compared by ANOVA to evaluate the relationship between PTEV and cytogenetic complexity. RESULTS: The PTEV of patients in normal (n=6), NCK (n=8), and CK (n=13) groups were 24.52±17.73, 34.26±35.04, and 86.31±48.7 cm3, respectively (P=0.005). Ten out of 11 patients with EGFR amplification showed abnormalities in chromosome 7. The mean PTEV of EGFR-amplified and non-amplified groups were 80.4±53.7 and 41.3±37.9 cm3, respectively (P=0.035). The average survival of patients with PTEV less than 90 cm3 was 30.52±26.11 months, while in patients with PTEVs over or equal to 90 cm3, it was 10.83±5.53 months (P=0.007). CONCLUSIONS: The results show an association of complex karyotype with the PTEV of high-grade astrocytoma. EGFR amplification plays a significant role in the formation of peritumoral edema, causing PTEV to increase, which is related with survival. This implies that cytogenetic karyotype can be applied as a prognostic factor.

Bilateral astrocytomas: Clinicoradiological characteristics and endoscopic management

Bithalamic astrocytoma is an extremely rare condtion associated with progressive neurobehavioural syndrome and dementia. We report a 17-year-old boy who presented with headache and memory loss. His magnetic resonance imaging revealed large bithalamic, symmetrical, non-enhancing lesions with moderate hydrocephalus and tonsillar herniation. Magnetic responance spectroscopy revealed high choline and creatinine peaks. An endoscopic guided biopsy and ventriculoperitoneal shunt placement was followed by radiotherapy. The biopsy revealed grade II fibrillary astrocytoma. He was initially relieved of raised pressure symptoms but developed tremors and progressive neruobehavioural dysfunction and died after 3 years

Consecutive cerebellar and cerebral astrocytomas.

An unusual astrocytoma occurring in different anatomical compartments of the brain is reported. The child was operated upon for a cerebellar astrocytoma when he was eight-and-half years old. Seven years later, he was operated for a cerebral astrocytoma. The growth of the similar tumours at these two sites is analysed and literature on the subject is reviewed. The concept of multicentricity is emphasized.