Surgical treatment of drug-resistant epilepsy caused by gliomas in eloquent areas: experience report / Tratamento cirúrgico de epilepsias refratárias causadas por gliomas localizados em áreas eloquentes: uma série de casos brasileiros

ABSTRACT Drug-resistant epilepsy associated with central nervous system tumors is generally caused by low grade gliomas. This group of tumors is usually found in brain eloquent areas, such as the insular lobe, rolandic cortex and supplementary motor area and, historically, possess a greater risk of postoperative deficits. Objective: The aim of this investigation was to present our surgical experience on patients with drug-resistant epilepsy caused by gliomas in eloquent areas. We retrospectively investigated variables that impact seizure control, such as tumor location, extent of resection, invasion into the lenticulostriate arteries in the patient, especially those with insular gliomas. Methods: Out of 67 patients with eloquent area brain tumors operated on in our service between 2007 and 2016, 14 patients had symptoms of drug-resistant epilepsy. Volumetric analysis, extent of resection (EOR), type of approach and mapping, among other factors were correlated with the 12-month postoperative seizure outcome. Results: Univariate analysis showed that the factors showing statistical relevance with seizure control were preoperative volume (p = 0.005), EOR (p = 0.028) and postoperative volume (p = 0.030). Conclusion: There was a statistically significant association between the EOR and the Engel score for epilepsy control: an EOR < 70 was associated with Engel II, III, IV and an EOR > 90 was associated with Engel I. Eloquent area gliomas can safely be resected when surgeons use not only microsurgical anatomy concepts but also brain mapping.

RESUMO Epilepsia refratária secundária a tumores cerebrais são geralmente causadas por gliomas de baixo grau. Esse grupo de tumor é frequentemente localizado em áreas eloquentes do cérebro como na insula, córtex rolândico e área motora suplementar; e sua ressecção apresenta alto risco de déficits neurológicos no pós operatório. Objetivo: O objetivo do estudo consiste em apresentar nossa experiência no tratamento cirúrgico de pacientes com epilepsia refratária secundário a gliomas em áreas eloquentes. Métodos: O estudo consiste em investigação retrospectiva de variáveis que interferem no controle de crises, tais como localização do tumor, grau de ressecção, invasão tumoral de artérias lenticulo estriadas, principalmente em gliomas insulares. Dentre 67 pacientes portadores de gliomas em área eloquente operados no período de 2007 a 2016, 14 doentes apresentavam epilepsia refrataria associada. Análise volumétrica do tumor, grau de ressecção, acesso cirúrgico, bem como o uso de mapeamento cortical intraoperatório foram correlacionados com desfecho de controle de crises epilepticas em 12 meses. Resultados: Em análise univariada os fatores relacionados com controle de crises em 12 meses foram volume tumoral pré operatório (p = 0,005), grau de ressecção (p = 0,028) e volume tumoral pós operatório. Conclusão: O grau de ressecção apresentou significância estatística em relação ao controle de crises conforme escala de Engel. Ressecções menores que 70% apresentaram correlação com Engel II, III e IV; enquanto ressecções maiores que 90% apresentaram correção positiva com Engel I. Gliomas em áreas eloquentes podem ser ressecados de forma segura desde que seja realizada por equipe experiente com conhecimento acurado da anatomia microcirúrgica e emprego de mapeamento cortical intraoperatório.

Re-Irradiation for Recurrent Gliomas: Treatment Outcomes and Prognostic Factors

PURPOSE: The aim of this study was to evaluate the efficacy of re-irradiation in patients with recurrent gliomas and to identify subgroups for whom re-irradiation for recurrent gliomas is most beneficial. MATERIALS AND METHODS: We retrospectively reviewed 36 patients with recurrent or progressive gliomas who received re-irradiation between January 1996 and December 2011. Re-irradiation was offered to recurrent glioma patients with good performance or at least 6 months had passed after initial radiotherapy (RT), with few exceptions. RESULTS: Median doses of re-irradiation and initial RT were 45.0 Gy and 59.4 Gy, respectively. The median time interval between initial RT and re-irradiation was 30.5 months. Median overall survival (OS) and the 12-month OS rate were 11 months and 41.7%, respectively. In univariate analysis, Karnofsky performance status (KPS) ≥70 (p<0.001), re-irradiation dose ≥45 Gy (p=0.040), and longer time interval between initial RT and re-irradiation (p=0.040) were associated with improved OS. In multivariate analysis, KPS (p=0.030) and length of time interval between initial RT and re-irradiation (p=0.048) were important predictors of OS. A radiographically suspected mixture of radiation necrosis and progression after re-irradiation was seen in 5 patients. CONCLUSION: Re-irradiation in conjunction with surgery could be a salvage treatment for selected recurrent glioma patients with good performance status and recurrence over a long time.

Análise de sobrevida e fatores prognósticos de pacientes pediátricos com tumores cerebrais / Analysis of survival and prognostic factors of pediatric patients with brain tumor

OBJETIVOS: Realizar análise de sobrevida e avaliar, através de análise multivariada, a influência de diversas variáveis na sobrevida, definindo fatores prognósticos de pacientes pediátricos com tumores do sistema nervoso central (SNC) tratados em um único centro. MÉTODOS: Analisamos, retrospectivamente, a sobrevida de 103 crianças portadoras de tumores cerebrais primários, diagnosticadas consecutivamente no período entre janeiro de 2000 e dezembro de 2006. Análise multivariada de fatores influenciando a sobrevida global por regressão de Cox foi usada para definir possíveis fatores prognósticos. RESULTADOS: A mediana e a média de idade foram de 7,2 e 7,6 anos. Houve predominância do sexo masculino (relação 1,22:1). A maioria dos pacientes tinha meduloblastoma ou tumores neuroectodérmicos primitivos (PNET, 38 por cento) ou astrocitomas de baixo grau (18 por cento). As topografias mais comuns foram cerebelar (49 por cento) e tronco cerebral (21 por cento). A sobrevida, 5 anos após o diagnóstico, foi de 84 por cento para astrocitomas de baixo grau e 51 por cento para meduloblastomas e PNET. Fatores prognósticos para a sobrevida global foram histopatológico (astrocitomas de alto grau e ependimomas, razão de risco entre 3,7 e 3,9), cirurgia (razão de risco 0,5 para tumores completamente ressecados) e radioterapia (razão de risco 0,5 para pacientes que receberam radioterapia). CONCLUSÕES: A sobrevida global de pacientes pediátricos com tumores cerebrais neste estudo é comparável àquela dos registros populacionais dos Estados Unidos e Europa. Os fatores de prognóstico definidos para sobrevida global também se assemelham àqueles previamente publicados.

OBJECTIVES: To estimate survival and evaluate prognostic factors of pediatric patients with central nervous system (CNS) tumors treated in a single center. METHODS: Retrospective analysis of survival of 103 children with primary brain tumors diagnosed consecutively from January 2000 to December 2006. Cox regression was used for multivariate analysis of factors that affect overall survival to define possible prognostic factors. RESULTS: Median and mean ages were 7.2 and 7.6 years. There was a male predominance (1.22:1). Most patients had medulloblastomas or primitive neuroectodermal tumors (PNET, 38 percent), or low-grade astrocytomas (18 percent). The anatomic site of most tumors was the cerebellum (49 percent) and the brain stem (21 percent). Five-year survival after diagnosis was 84 percent for low-grade astrocytomas and 51 percent for medulloblastomas and PNET. Prognostic factors for overall survival were histopathological type (high-grade astrocytomas and ependymomas; hazard ratio = 3.7 to 3.9), surgery (hazard ratio of 0.5 for completely resected tumors) and radiotherapy (hazard ratio of 0.5 for patients who underwent radiotherapy). CONCLUSIONS: Overall survival of pediatric patients with brain tumors in this study was similar to that found in populations of the United States and Europe. The prognostic factors defined for overall survival are also similar to those published in previous studies.

The role of surgery in the management of intracranial gliomas: current concepts.

The role of surgery in the management of human gliomas has been controversial. The results from numerous neurosurgical series are inconsistent. The current adjuvant therapies have facilitated treatment of patients, and have rendered neurosurgical removal without morbidity or mortality more commonplace than ever before. Here, we investigated the role of surgery in the management of adults with low- and high-grade gliomas. Even though there is substantial evidence which claims that surgery per se has a role to play in extending patient survival, there is a paucity of randomized clinical trials on this subject, and little in the way of Class II data to support these claims. However, this should not divert patients away from surgery, because there may be additional benefits from a concerted effort to remove a tumor completely. At the present time, it seems best that clinicians continue to individualize patient treatment based on a myriad of factors that relate to the patient, the patient's tumor, and the known biology of the disease.

Biopsias estereotáxicas: resultados en el manejo de gliomas de alto grado en el Hospital Carlos Van Buren 2000-2007 / Stereotactic biopsies: results in the management of high-grade gliomas in the Hospital Carlos Van Buren

Con el objetivo de comparar dos grupos similares de pacientes portadores de gliomas de alto grado diagnòsticados uno vìa estereotáxica y otro vía craneotomía, se diseño un estudio retrospectivo entre los años 2000 y 2007, con un diseño de casos y controles en el Hospital Carlos Van Buren de Valparaíso; los casos fueron los pacientes portadores de glioma de alto grado diagnósticado vía estereotáxica, los controles fueron pacientes similares pero diagnósticados vía biopsia quirúrgica convencional. Se recolectaron los datos de 19 pacientes biopsiados estereotáxicamente y de 15 enfermos biopsiados por craneotomía, no encontrándose diferencias significativas en cuanto a sexo, edad y localización tumoral entre ambos grupos, tampoco se encontraron diferencias significativas entre el Karnosfky performance status de ingreso y egreso hospitalario, las complicaciones y la mortalidad entre ambos grupos. La estadía hospitalaria postprocedimiento fue significativamente menor en el grupo biopsiado estereotáxicamente (p=0,0254). La mediana del costo fue en el caso de la estereotaxia de $444.070 pesos chilenos (U$925) y de $990.480 pesos chilenos (US2063) en el caso de las biopsias por craneotomía. Se aprecio una mayor sobrevida a dos años y medio en el grupo biopsiado por estereotáxia (p=0,169) . La obtención de una biopsia mediante estereotaxia no demostró asociarse a mayores complicaciones, morbilidad o mortalidad respecto a la biopsia tradicional, en el presente estudio. Asociándose a una menor estadía postprocedimiento, menores costos y una mayor sobrevida a dos años y medio, lo que hace altamente recomendable la realización de este tipo de técnica en pacientes que se sospeche la presencia de un glioma de alto grado.

Prognostic value of TP53 Pro47Ser and Arg72Pro single nucleotide polymorphisms and the susceptibility to gliomas in individuals from Southeast Brazil

The TP53 tumor suppressor gene codifies a protein responsible for preventing cells with genetic damage from growing and dividing by blocking cell growth or apoptosis pathways. A common single nucleotide polymorphism (SNP) in TP53 codon 72 (Arg72Pro) induces a 15-fold decrease of apoptosis-inducing ability and has been associated with susceptibility to human cancers. Recently, another TP53 SNP at codon 47 (Pro47Ser) was reported to have a low apoptosis-inducing ability; however, there are no association studies between this SNP and cancer. Aiming to study the role of TP53 Pro47Ser and Arg72Pro on glioma susceptibility and oncologic prognosis of patients, we investigated the genotype distribution of these SNPs in 94 gliomas (81 astrocytomas, 8 ependymomas and 5 oligodendrogliomas) and in 100 healthy subjects by the polymerase chain reaction-restriction fragment length polymorphism approach. Chi-square and Fisher exact test comparisons for genotype distributions and allele frequencies did not reveal any significant difference between patients and control groups. Overall and disease-free survivals were calculated by the Kaplan-Meier method, and the log-rank test was used for comparisons, but no significant statistical difference was observed between the two groups. Our data suggest that TP53 Pro47Ser and Arg72Pro SNPs are not involved either in susceptibility to developing gliomas or in patient survival, at least in the Brazilian population.

Therapeutic Effects of Holmium-166 Chitosan Complex in Rat Brain Tumor Model

This study examined the effectiveness of Holmium-166 (Ho-166) chitosan complex therapy for a malignant glioma. Cultured C6 glioma cells (100, 000 in 5microliter) were injected into the caudate/putamen of 200 - 250 gram Wistar rats. Five days later, a Ho-166 chitosan complex was injected into the same site of the glioma injection. Four injection doses were administered: the control group received PBS 10microliter, group 1 received an injection of 100micro Ci (10microliter), group 2 received an injection of 50microCi (5microliter), and group 3 received an injection of 10micro Ci (1microliter). The average tumor volume for each group was 1.385 mm3 for the control group, 0.036 mm3 for group 1, 0.104 mm3 for group 2, and 0.111 mm3 for group 3. Compared with the control group, the size of the tumors in groups 1, 2 and 3 was reduced by an average of 97.4%, 92.5% and 91.9%, respectively. The Kaplan-Meier survival curve of group 2 was the longest, followed by groups 3, group 1 and the control. The mean survival was 22.8, 59, 60, and 44.6 days for the control group and groups 3, 2 and 1, respectively. H-E staining revealed that group 2 yielded the best results in the destruction of the malignant glioma. TUNEL staining and immunohistochemical studies indicated apoptotic features. The Ho-166 chitosan complex proved to be effective in destroying the malignant glioma.

Glioma del nervio óptico

Se presenta un revisión clínico-patológica de 8 casos de gliomas del nervio y quiasma ópticos. Seis de los casos ocurrieron en niños y dos en adultos. En dos casos se presentó síndrome diencefálico, uno de ellos se demostró en la autopsia. Se presentan los hallazgos histopatológicos, ultraestructurales e inmunohistoquímicos, con especial atención a las fibras de Rosenthal y a la proteína ácida gliofibrilar. Se menciona la utilidad del empleo de la microscopía electrónica e inmunohistoquímica en el diagnóstico diferencial de estas neoplasias.