Terapias dirigidas con inhibidores del braf en gliomas pediátricos de alto y bajo grado con la mutación brafv600e. Experiencia del hospital Prof. Dr. Juan P. Garrahan / Targeted therapies with BRAF inhibitors for pediatric low- and high-grade gliomas with BRAF v600e mutation. Prof. Dr. Juan P. Garrahan Hospital experience

Resumen La mutación puntual V600E del gen BRAF juega un papel fundamental en la tumorigénesis de muchos gliomas. La inhibición de su producto forma parte de terapias innovadoras emergentes en los últimos años. Conocer el rol de estos tratamientos resulta imprescindible. El objetivo del trabajo fue describir la respuesta clínico-radiológica en niños con gliomas BRAF V600E mutado tratados con inhibidores BRAF. Para ello se realizó un estudio descriptivo y retrospectivo en pacientes menores de 16 años con gliomas BRAF V600E mu tado que recibieron vemurafenib o dabrafenib en el Hospital Garrahan. Trece pacientes tratados en los últimos 7 años fueron incluidos: 9 gliomas de bajo grado y 4 de alto grado. La mediana de edad al diagnóstico fue 8.6 años (0.89-14.04) y del comienzo del inhibidor 11.62 años (3.64-15.42). Inicialmente, todos habían realizado tratamiento quirúrgico, y 12/13 recibieron previamente otra terapia: 11 quimioterapia (eventualmente hasta 4 líneas distintas) y 4 radioterapia. Con la terapia dirigida, 10 pacientes tuvieron una disminución tumoral mayor o igual al 25%, quedando evidenciada en 7 niños la mejor respuesta dentro de los 6 meses del inicio. Hubo 4 progresados intratratamiento (todos alto grado), y 2 progresados prontamente luego de suspender el inhibidor (ambos bajo grado). Cinco presentaron efectos adversos grado 3-4, con recuperación ad-integrum. Se describe una buena y sostenida respuesta clínico-radiológica, con tolerancia aceptable, en pacientes con gliomas de bajo grado BRAF V600E mutado tratados con inhibidores BRAF V600E . En contraste, la respuesta en pacientes con gliomas de alto grado fue intermedia y de poca duración, con progresión tumoral precoz.

Abstract The BRAF V600E point mutation plays a key role in the tumorigenesis of many gliomas. Inhibiting its product is part of the innovative therapies emerging in recent years. Knowing the role of these treatments is essential. The aim of this experience was to describe the clinical-radiological response of pediatric BRAF V600E mutated gliomas treated with BRAF inhibitors. To this end, a descriptive and retrospective study was performed in patients under 16 years of age with BRAF V600E gliomas, who received vemurafenib or dabrafenib at Hospital Garrahan. Thirteen patients treated in the last 7 years were included: 9 were low-grade and 4 high-grade gliomas. The median age at diagnosis was 8.6 years (0.89-14.04) and at start of targeted therapy was 11.62 years (3.64-15.42). All patients had previously a surgical procedure, and 12/13 had received another therapy prior BRAF inhibition: 11 chemotherapy (in one case, up to 4 different protocols) and 4 radiotherapy. Under targeted therapy, tumour response was obtained in 10 patients (size reduction equal to or greater than 25%), and best response was observed in the first 6 months of treatment in 7 children. Four patients progressed under treatment (all high-grade gliomas) and 2 progressed shortly after stopping the inhibitor (both low-grade gliomas). Five patients had grade 3-4 toxicity, with subsequent full recovery. A good and sustained clinical-radiological response, with acceptable tolerance, is described in patients with BRAF V600E mutated low-grade gliomas treated with BRAF V600E inhibitors. In contrast, the response in patients with high-grade gliomas was intermediate and of short duration, with early tumour progression.

Establishment of a mouse model bearing orthotopic temozolomide-resistant glioma / 南方医科大学学报

OBJECTIVE@#To establish a mouse model bearing orthotopic temozolomide (TMZ)-resistant glioma that mimics the development of drug resistance in gliomas @*METHODS@#Seventy-eight adult C57BL/6 mice were randomly divided into 6 groups (@*RESULTS@#The mouse models bearing TMZresistant glioma was successfully established. The cells from the high-dose induced group showed a significantly higher colony-forming rate than those from the high-dose control group (@*CONCLUSIONS@#Progressive increase of TMZ doses in mice bearing orthotopic gliomas can effectively induce TMZ resistance of the gliomas.

DNMT1 mediates chemosensitivity by reducing methylation of miRNA-20a promoter in glioma cells

Although methyltransferase has been recognized as a major element that governs the epigenetic regulation of the genome during temozolomide (TMZ) chemotherapy in glioblastoma multiforme (GBM) patients, its regulatory effect on glioblastoma chemoresistance has not been well defined. This study investigated whether DNA methyltransferase (DNMT) expression was associated with TMZ sensitivity in glioma cells and elucidated the underlying mechanism. DNMT expression was analyzed by western blotting. miR-20a promoter methylation was evaluated by methylation-specific PCR. Cell viability and apoptosis were assessed using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) and TdT-mediated dUTP-biotin nick end labeling assays, respectively. The results showed that compared with parental U251 cells, DNMT1 expression was downregulated, miR-20a promoter methylation was attenuated and miR-20a levels were elevated in TMZ-resistant U251 cells. Methyltransferase inhibition by 5-aza-2\'-deoxycytidine treatment reduced TMZ sensitivity in U251 cells. In U251/TM cells, DNMT1 expression was negatively correlated with miR-20a expression and positively correlated with TMZ sensitivity and leucine-rich repeats and immunoglobulin-like domains 1 expression; these effects were reversed by changes in miR-20a expression. DNMT1 overexpression induced an increase in U251/TM cell apoptosis that was inhibited by the miR-20a mimic, whereas DNMT1 silencing attenuated U251/TM cell apoptosis in a manner that was abrogated by miR-20a inhibitor treatment. Tumor growth of the U251/TM xenograft was inhibited by pcDNA-DNMT1 pretreatment and boosted by DNMT1-small hairpin RNA pretreatment. In summary, DNMT1 mediated chemosensitivity by reducing methylation of the microRNA-20a promoter in glioma cells.

Característica clínica e topográfica do glioma maligno em adolescente - Influência do tratamento intranasal com álcool perílico / Clinical and topographic characteristics of primary glioma in youth - Influence the response to perillyl alcohol treatment

Objetivo: Analisar a influência da topografia da lesão tumoral na resposta ao tratamento intranasal com álcool perílico (POH) em jovens com glioma maligno recidivo. Método: Tendo como padrão a faixa etária de 0 a 19 anos, foram incluídos pacientes do sexo masculino (#153; #31) e feminino (#178) com glioma maligno em estágio terminal, recebendo terapia de suporte paliativa e administração intranasal diária de 440 mg de POH. Resultados: Cefaleia intensa, tontura, vômito, crise convulsiva, alteração de comportamento, fraqueza muscular, alteração visual e hemiplegia à direita foram os sintomas prevalentes antes da confirmação diagnóstica de glioma. Análise de imagem mostrou lesão tumoral nas regiões troncocerebral (#153), talamomesencefálica esquerda (#178) e frontotemporal e insular direita (#31). Paciente #178 não respondeu ao tratamento, evoluindo a óbito em três semanas, e paciente #31 permaneceu em tratamento com POH por aproximadamente 54 semanas. Apesar de nova recidiva, paciente #153 apresenta doença estável, sem qualquer evidência clínica de recorrência para mais de 200 semanas em tratamento exclusivo com álcool perílico por via intranasal. Conclusão: Pacientes adolescentes com glioma maligno recidivo apresentaram heterogeneidade de sintomas compatível coma região anatômica comprometida, indicando que a topografia da lesão tumoral foi um fator prognóstico de sobrevida, influenciando inclusive na resposta ao tratamento intranasal com o álcool perílico.

Objective: Analyze the influence of tumor topography on response to intranasal perillyl (POH) treatment in youths with high grade glioma. Method: It was included male patients (#153; #31) with 19 years old and female (#178) with 15 years old with recurrent high grade glioma in terminal stage using supportive therapy and 440 mg POH daily intranasal administration. It was established a relation of clinical data and topographic image with therapeutic response to intranasal POH. Results: Intense headache, dizziness, vomiting, seizures, behavior change, muscle weakness, visual changes and right hemiplegia were the symptoms prevalent before the diagnostic confirmation of glioma. Image analysis showed tumoral lesionin the brain-stem (#153), in the left thalamus-mesencephalic region (#178), and right frontal-temporal and insular regions (#31). Patient #178 did not respond to intranasal POH treatment and rapidly progressed to death within 3 weeks; patient #31 remained in treatment with POH for nearly 54 weeks, and despite new recurrence, patient #153 presents stable disease, without any clinical evidence of recurrence for more than 200 weeks and under treatment exclusively with POH by intranasal route. Conclusion: Childhood patients with high grade malignant glioma had heterogeneity of clinical symptoms compatible with anatomical compromised region indicating that topography of the tumoral lesion was a prognostic factor influencing the overall survival and response to intranasal POH.

Therapeutic concentration of morphine reduces oxidative stress in glioma cell line

Morphine is a potent analgesic opioid used extensively for pain treatment. During the last decade, global consumption grew more than 4-fold. However, molecular mechanisms elicited by morphine are not totally understood. Thus, a growing literature indicates that there are additional actions to the analgesic effect. Previous studies about morphine and oxidative stress are controversial and used concentrations outside the range of clinical practice. Therefore, in this study, we hypothesized that a therapeutic concentration of morphine (1 μM) would show a protective effect in a traditional model of oxidative stress. We exposed the C6 glioma cell line to hydrogen peroxide (H2O2) and/or morphine for 24 h and evaluated cell viability, lipid peroxidation, and levels of sulfhydryl groups (an indicator of the redox state of the cell). Morphine did not prevent the decrease in cell viability provoked by H2O2 but partially prevented lipid peroxidation caused by 0.0025% H2O2 (a concentration allowing more than 90% cell viability). Interestingly, this opioid did not alter the increased levels of sulfhydryl groups produced by exposure to 0.0025% H2O2, opening the possibility that alternative molecular mechanisms (a direct scavenging activity or the inhibition of NAPDH oxidase) may explain the protective effect registered in the lipid peroxidation assay. Our results demonstrate, for the first time, that morphine in usual analgesic doses may contribute to minimizing oxidative stress in cells of glial origin. This study supports the importance of employing concentrations similar to those used in clinical practice for a better approximation between experimental models and the clinical setting.

LRIG1 Enhances Chemosensitivity by Modulating BCL-2 Expression and Receptor Tyrosine Kinase Signaling in Glioma Cells

PURPOSE: Leucine-rich repeats and immunoglobulin-like domains 1 (LRIG1) are an inhibitor of receptor tyrosine kinases (RTKs) that was discovered in recent years, and many studies showed that LRIG1 is a tumor suppressor gene and may be related to tumor drug resistance. In this study, we explored whether LRIG1 protein expression can improve the chemosensitivity of glioma cells and what was its mechanism. MATERIALS AND METHODS: We collected 93 cases of glioma tissues and detected the expression of LRIG1 and BCL-2. We constructed a multidrug resistance cell line U251/multidrug resistance (MDR) and examined the change of LRIG1 and BCL-2 at mRNA and protein expression levels. LRIG1 expression was upregulated in U251/MDR cells and we detected the change of multidrug resistance. Meanwhile, we changed the expression of LRIG1 and BCL-2 and explored the relationship between LRIG1 and BCL-2. Finally, we also explored the relationship between LRIG1 and RTKs. RESULTS: LRIG1 was negatively correlated with BCL-2 expression in glioma tissue and U251/MDR cells, and upregulation of LRIG1 can enhance chemosensitivity and inhibit BCL-2 expression. Furthermore, LRIG1 was negatively correlated with RTKs in U251/MDR cells. CONCLUSION: These results demonstrated that LRIG1 can improve chemosensitivity by modulating BCL-2 expression and RTK signaling in glioma cells.

Toxicity Profile of Temozolomide in the Treatment of 300 Malignant Glioma Patients in Korea

This study evaluated the toxicity profiles of temozolomide in the treatment of malignant glioma as either concurrent or adjuvant chemotherapy. We retrospectively reviewed the medical records of 300 malignant glioma patients treated with temozolomide in two medical institutions in Korea between 2004 and 2010. Two hundred nine patients experienced a total of 618 toxicities during temozolomide therapy. A total of 84.8% of the 618 toxicities were Common Terminology Criteria for Adverse Events (CTCAE) grade 1 or 2, while 15.2% were grade 3 or 4. Among the hematologic toxicities, thrombocytopenia (13.7%), anemia (11.0%), and AST/ALT increases (7.0%) were common. Among the non-hematologic toxicities, nausea (44.3%), vomiting (37.0%), and anorexia (14.3%) were the three most common toxicities. There was no mortality due to temozolomide. Although temozolomide showed many types of toxicities, the majority of the toxicities were tolerable and of lower grade. Gastrointestinal troubles are the most common toxicities in Korean patients treated with temozolomide.

Temozolomida para o tratamento adjuvante de pacientes portadores de gliomas de alto grau / Temozolomide for the adjuvant treatment of patients with high grade gliomas

CONTEXTO: Gliomas de alto grau são tumores cerebrais, na sua maioria primários, que apresentam crescimento muito agressivo, rápida evolução e alta letalidade. Estes tumores são tratados com ressecção cirúrgica quando possível e com radioterapia. A quimioterapia adjuvante realizada com diversos esquemas de drogas pode aumentar a sobrevida dos pacientes quando comparada à radioterapia isolada, no entanto, tratando-se de benefício na extensão da sobrevida em poucas semanas e com qualidade de vida prejudicada, a decisão por instituir a quimioterapia ou não deve ser tomada pela família e paciente devidamente esclarecidos pelo médico assistente. Temozolomida é um dos medicamentos indicados para a quimioterapia adjuvante (realizada após o procedimento cirúrgico ou radioterápico) desses tumores. É um pró-fármaco, o que significa que depende de uma transformação no corpo do paciente para se converter no medicamento ativo, o MTIC, sigla de 5-(3-metiltriazeno-1-il)imidazol-4-carboxamida, que possui atividade citotóxica cerebral. Devido a doença apresentar rápida evolução e alta mortalidade, a quimioterapia adjuvante, inclusive aquela com temozolomida, se propõe a aumentar a sobrevida deste pacientes. Estima-se que, no Brasil, cerca de 3.000 pessoas poderiam ser potenciais usuárias desta tecnologia. Desta forma, a Secretaria de Estado da Saúde de São Paulo solicita a incorporação nacional desta tecnologia. TRATAMENTO RECOMENDADO: O arsenal terapêutico passa pelos três grupos básicos de tratamento: Cirurgia - A ressecção cirúrgica é o tratamento recomendado na maioria dos casos de tumor cerebral, com objetivo de remover amplamente a neoplasia com a máxima preservação do tecido normal adjacente e das funções neurológicas. Eventualmente, a localização do tumor em área eloquente permite apenas citorredução ou biópsia da lesão. Doentes com hidrocefalia podem necessitar ventriculostomia ou derivação ventriculoperitoneal para paliação de sintomas. Gastrostomia está indicada quase sempre que houver comprometimento da deglutição ou do reflexo da tosse. Radioterapia - A radioterapia desempenha um papel central no tratamento paliativo do tumor cerebral, na doença inicialmente inoperável ou recorrente. A irradiação focal por meio de técnicas convencionais permite estabilizar ou melhorar a condição funcional de muitos doentes. A dose empregada situa-se entre 54-60 Gy, podendo atingir 72 Gy com hiperfracionamento; o campo irradiado deve incluir a área de realce visível à TC com margens de 2-3 cm ou margem de 1-2 cm em torno da imagens de RM ponderadas em T2. Doentes com lesão pequena (até 4 cm) e contra-indicação para cirurgia podem se beneficiar de radioterapia focal estereotática. Quimioterapia - A quimioterapia antineoplásica é pouco ativa para o câncer cerebral, produzindo benefício clínico temporário para alguns doentes. A necessidade de uso concomitante de medicamentos anticonvulsivantes para muitos doentes parece estar associada a melhor prognóstico, em particular com o ácido valproico, a despeito de toxicidade variável. Esquemas terapêuticos, quimioterápicos, contendo nitrosureias (carmustina ou lomustina), alquilantes (procarbazina, dacarbazina ou temozolomida), derivados da platina (cisplatina ou carboplatina), vincristina, teniposiído, hidroxiureia, cloroquina, bevacizumabe e irinotecano se mostraram úteis no tratamento paliativo de gliomas cerebrais grau III ou IV, muitos deles administrados concomitantemente à radioterapia. A temozolomida é um medicamento oral relacionado a um antineoplásico clássico, a dacarbazina; enquanto a dacarbazina requer metabolização hepática para produção do agente antineoplásico clinicamente ativo (monometiltriazenoimidazol carboxamida, MTIC), a temozolomida é convertida em MTIC no plasma. Em dois estudos clínicos randomizados sobre temozolomida em associação à radioterapia para gliomas de alto grau, este tratamento mostrou ser ativo quando comparado com placebo, outros estudos demonstraram eficácia comparável da temozolomida e do esquema PCV (procarbazina, lomustina e vincristina) para doentes com gliomas de alto grau ou com astrocitoma anaplásico. A TECNOLOGIA: A temozolomida é um agente antineoplásico, que exerce sua ação citotóxica por alquilação do DNA nas posições O(6) e N(7) da guanina. É rapidamente absorvido por via oral, com alta biodisponibilidade (96% a 100%). A presença de alimento diminui o pico de concentração plasmática em 32% e a AUC em 9%. É um pró-fármaco que, após hidrólise espontânea no plasma, é convertido ao seu metabólito ativo, o MTIC, sigla de 5-(3-metiltriazeno-1-il)imidazol-4-carboxamida, que possui atividade citotóxica. Aproximadamente 15% do fármaco se liga às proteínas plasmáticas. É excretado pela urina (37,7%) e pelas fezes (0,8%). O tempo de meia vida é de 1,5 a 2,35 horas. Por ser uma substância lipofílica, atravessa a barreira hemato-encefálica, o que a faz alcançar tumores cerebrais. ANÁLISE DA EVIDÊNCIA: O objetivo deste relatório é analisar as evidências científicas apresentadas pela Secretaria de Estado da Saúde de São Paulo sobre eficácia, segurança, custo-efetividade e impacto orçamentário do Temozolomida (TEMODAL®), para o tratamento de gliomas de alto grau, visando avaliar a sua incorporação no Sistema Único de Saúde.CONSIDERAÇÕES FINAIS: O desafio nesse tipo de câncer é que, apesar das inovações em técnicas cirúrgicas e radioterápicas e do desenvolvimento de novos medicamentos antineoplásicos que aconteceram nas últimas décadas, os gliomas malignos, em especial os de alto grau, permanecem doenças fatais. São altas as taxas de morte no primeiro ano, sendo que a maioria dos pacientes já foi a óbito em dois anos após o diagnóstico. A evidência atualmente disponível sobre eficácia e segurança da temozolomida para tratamento de gliomas de Alto Grau ( estádios II e IV) é baseada em ensaios clínicos randomizados, com nível de evidência 1. Neste sentido, os resultados apresentados pelos estudos de Hart (2013) sugerem que o tamanho do efeito é de HR=0,60 e a mediana de sobrevida é de 2,5 meses para o grupo que usou temozolomida. A taxa de sobrevida aos 12 meses é de 61,1% para o grupo de temozolomida + radioterapia com uma redução do risco absoluto (RRA) de 10,5% e NNT de 10. No entanto, o principal problema do estudo apresentado pelo demandante foi o estabelecimento equivocado da pergunta de pesquisa: temozolamida + radioterapia é superior à radioterapia isolada em gliomas de alto grau? Não há duvidas quanto a isso, tanto que desde 1999 o tratamento no SUS para esse tipo de tumor é quimioterapia associada à radioterapia, cabendo ao médico e ao paciente e familiares decidirem se esse aumento de sobrevida com prejuízo da qualidade de vida é desejável. A questão clinica relevante seria saber se a quimioterapia com temozolamida, novo medicamento de alto custo e sob patente, é superior à quimioterapia com os demais agentes alquilantes já disponíveis. Como estes estudos de comparação entre tipos de quimioterapia não foram incluídos pelo demandante, foi realizada uma busca que revelou estudos que demonstraram equivalência terapêutica da temozolomida versus quimioterapia por dacarbazina, análogo injetável da temozolamida, que é oral, no tratamento de gliomas de alto grau. Ademais, o modelo econômico apresentado pelo demandante levanta um alto grau de incerteza que não permite concluir que a RCEI apresentada seja robusta suficiente para discussão da sua incorporação. DELIBERAÇÃO FINAL: Os membros da CONITEC presentes na 23ª reunião do plenário dos dias 12 e 13/03/2014, deliberaram, por unanimidade, por não recomendar a incorporação de procedimento quimioterápico específico compatível com a temozolamida para o tratamento pós-operatório de pacientes com gliomas de alto grau( III e IV). DECISÃO: PORTARIA Nº 35, de 26 de setembro de 2014 - Torna pública a decisão de não incorporar a temozolamida para o tratamento pós-operatório de pacientes portadores de gliomas de alto grau no âmbito do Sistema Único de Saúde - SUS.

The inhibitory effect of photodynamic therapy and of an anti-VCAM-1 monoclonal antibody on the in vivo growth of C6 glioma xenografts

We investigated the effect of photodynamic therapy (PDT) and of an anti-vascular cell adhesion molecule-1 (VCAM-1) monoclonal antibody on the in vivo growth of C6 glioma. Seven days after inoculation with C6 cells, adult male Wistar rats weighing 280-300 g with MRI-confirmed glioma were randomly assigned to 4 groups (N = 15 per group): PDT + VCAM-1 antibody group; PDT group; VCAM-1 antibody group; control group. Eight days after inoculation, hematoporphyrin monomethyl ether (HMME) was administered as a photosensitizer and PDT was performed at 630 nm (illumination intensity: 360 J/cm²) for 10 min. VCAM-1 antibody (50 µg/mL) was then administered (0.5 mL) through the tail vein every other day from day 8 to day 16. At day 21, 5 rats in each group were sacrificed and cancers were harvested for immunohistochemistry and Western blot assay for the detection of VCAM-1, and TUNEL assay was used to detect apoptosis. Survival and tumor volume were recorded in the remaining 10 rats in each group. In the PDT group, tumor growth was significantly suppressed (67.2 percent) and survival prolonged (89.3 percent), accompanied by an increase in apoptosis (369.5 percent), when compared to control. Furthermore, these changes were more pronounced in the PDT + VCAM-1 antibody group. After PDT, VCAM-1 expression was markedly increased (121.8 percent) and after VCAM-1 monoclonal antibody treatment, VCAM-1 expression was significantly reduced (58.2 percent). PDT in combination with VCAM-1 antibody can significantly inhibit the growth of C6 glioma and prolong survival. This approach may represent a promising strategy in the treatment of glioma.

Correlação da topografia tumoral e edema peritumoral com a resposta terapêutica à administração intranasal do álcool perílico nos gliomas malignos recidivos / Correlation of tumor topography and peritumoral edema with therapeutic response to a new approach for recurrent malignant gliomas, intranasal administration of perillyl alcohol

Objetivo: Avaliar a correlação da topografia tumoral e edema peritumoral com a resposta terapêutica à administração intranasal do álcool perílico (AP) em uma coorte de pacientes com gliomas malignos recidivos. Métodos: Os autores revisaram retrospectivamente 67 pacientes com gliomas malignos recidivos que receberam administração intranasal de 440 mg de AP diariamente. Parâmetros avaliados incluíram aspectos clínicos e os de neuroimagem. Avaliação clínica incluiu dados demográficos, sintomas iniciais e sobrevida global. Dados de imagem incluíram topografia tumoral, volume tumoral, presença de desvio da linha média eextensão de edema peritumoral. Análise bioestatística foi realizada usando testes log rank. Sobrevida global foi medida e analisada pelo método de Kaplan Meier, incluindo intervalos de confiança de 95 por cento. Resultados: Um total de 67 pacientes foi investigado, 52 (77,6 por cento) com glioblastoma (GBM), 10 (14,9 por cento) com astrocitoma anaplásico (AA) e 5 (7,4 por cento) com oligodendrioglioma anaplásico (OA). Todos os cinco pacientes com AO apresentaram tumor de localização lobar. Nos AA, oito casos estavam localizados em região talâmica e dois em região lobar, enquanto que, nos GBM, 11 casos de localização talâmica e 41 lobares. A relação volume tumoral e edema peritumoral foi observada. Pacientes com regressão tumoral e edema peritumoral apresentaram resposta positiva enquanto que aqueles com regressão tumoral sem regressão do edema peritumoral não apresentaram boa evolução clínica. Pacientes com gliomas profundos sobreviveram significativamente mais tempo do que aqueles com gliomas lobares (log rank test, p = 0,0003). Presença de desvio da linha média (> 1 cm) foi estatisticamente significante como fator de risco para a sobrevida mais curta (log rank test,p = 0,0062). Conclusões...

To evaluate the correlation of tumor topography and peritumoral brain edema with the therapeutic response of intranasal administration of perillyl alcohol (POH) in a cohort of patients with recurrent malignant gliomas. Methods: We retrospectively reviewed 67 consecutive patients with recurrent malignant gliomas who received administration intranasal of POH 440 mg daily. The parameters evaluated were clinical features and the neuroimaging findings. Clinical data included demographics, initial symptoms, and overall survival.Imaging analysis included tumor topography, tumor size, presence of midline shift and extent of peritumoraledema. Biostatistics was carried out using log rank tests. Overall survival was measure and analyzedby Kaplan Meier method including 95% confidence intervals. A total of 67 patients were investigated,52 (77.6%) with glioblastoma (GBM), 10 (14.9%) with anaplastic astrocytoma (AA) and 5 (7.4%) withanaplastic oligodendroglioma (AO). All five AO had lobar localization, AA were lobar in 8 cases and deep in 2 cases, whereas GBM were lobar in 41 cases and deep in 11 cases. Results: A relationship between the tumor size and the volume of peritumoral brain edema (PTBE) was observed. Patients with regression of the tumor and PTBE had positive response whereas those with regression of the tumor without PTBE regression had poor prognosis. Patients with deep tumors survived significantly longer than those with lobar gliomas (log rank test, p=0.0003). Presence of midline shift (> 1 cm) was a statistically significant risk factor for shorter survival (log rank test, p=0.0062). Conclusions...

Evidence-based adjuvant therapy for gliomas: current concepts and newer developments.

The incidence of gliomas is increasing worldwide, including India. Of the 18,820 new cases of primary central nervous system (CNS) tumors diagnosed annually in the United States, gliomas account for over 60% with 30-40% of them being glioblastoma multiforme (GBM), 10% being anaplastic astrocytoma (AA), and 10% being low grade gliomas (LGGs). This is in contrast to one study from West Bengal, India, in which only 7.9% of the brain tumors were GBMs, while 46.8% were astrocytomas. Of all adult primary CNS tumors, GBM is the most common and the most malignant with about 7,000 to 8,000 new cases annually in the United States. Given poor outcomes, a number of treatment approaches have been investigated. Common to these approaches is the use of adjuvant radiation therapy, even as surgery alone, with or without chemotherapy, may be the mainstay for some lower grade and low-risk gliomas. Today, treatment typically involves external beam radiation, with concurrent and adjuvant chemotherapy for more aggressive histologies. Although gliomas are relatively uncommon, active research is ongoing. Results of landmark trials along with some of the recently published trials are presented. These trials and management strategies as well as evolving concepts are found by reviewing over 200 articles in the National Library Medical (NLM) database, PubMed, more than 60 of which are refrenced. Specifically, the database is searched using the following keywords, with various combinations: glioma, low-grade, anaplastic, astrocytoma, oligodendroglioma, oligoastrocytoma, glioblastoma multiforme, chemotherapy, radiation, new concepts, phase III, MGMT, CDX-110 (Celldex), temozolomide, 1p/19q deletion, and bevacizumab.

A multivariate analysis of patients with glioma: a treatment outcome and prognostic factor for survival.

OBJECTIVE: To evaluate the treatment outcome and to examine the influence of factors on survival of patients with glioma. MATERIAL AND METHOD: One hundred and eighty-nine patients were included. Data on the patient's age, sex, KPS score, tumor location and survival time were collected and analyzed. RESULTS: Tumor grade and age had effect on survival of the patients. The median survival time (MST) of patients with grade II-IV glioma was 80.0, 20.0 and 9 months, respectively. Only the tumor site had influence on survival of patients with grade II glioma. In patients with grade III glioma, only KPS score had an impact on survival. In patients with grade IV glioma, none of the factors had an effect on survival. CONCLUSION: The treatment outcome of the patients in Chulalongkorn University is comparable to other series. Multivariate analysis identified factors that had influence on survival of the patients.

Detecção imuno-histoquímica de células apoptóticas em glioblastoma recidivante de paciente tratado com álcool perílico por via inalatória / Immunohistochemical detection of apoptotic cells in a recurrent glioblastoma patient treated with intranasal delivery of perillyl alcohol

Introdução: Estudos in vitro mostram que radioterapia e/ou quimioterapia podem ativar as vias de sinalizaçãodo receptor do fator de crescimento epidérmico (EGFR) e Ras, aumentando a resistência cruzada dascélulas de glioblastomas multiformes (GBM) ao tratamento. A inibição das atividades de EGFR e Rasatravés de inibidores tirosinas cinases elimina o antagonismo observado à administração seqüencialdestas modalidades terapêuticas, induzindo apoptose nestas células. Em estudo prévio demonstramosque o tratamento com o álcool perílico (AP), inibidor da farnesilação da Ras, induz apoptose em linhagenscelulares e células de explante de GBM. Objetivo: No presente estudo investigamos se a regressãoparcial observada em GBM recorrente de paciente tratado com administração intranasal de AP é mediadapor apoptose. Resultado: Ensaios com TUNEL (deoxynucleotidyl-mediated deoxyuridine triphosphate) ecaspase-3 ativada evidenciaram presença de células apoptóticas nas lâminas de GBM tratado. Conclusão:Esses achados sugerem que estratégias adjuvantes visando à inativação das vias de sinalização do EGFRe Ras podem melhorar tanto a eficácia de terapia isolada como de terapia multimodal em gliomas.

Background: In vitro studies demonstrated that both radiation and chemotherapy can activate EGFRand Ras signaling pathways, leading to increased cross-resistance to treatment of GBM cell. Inhibition of either EGFR or Ras activity with tytosine kinase inhibitor appears to abrogate the observed antagonism between sequentially administration of these therapeutic modalities inducing apoptosis in these cells. In a previous study, we demonstrated that in vitro treatment with perillyl alcohol (POH), an inhibitor of Ras farnezilation, induced apoptosis in human GBM cell lines and explants. Objective: In the presentstudy, we investigated if the partial regression observed in a patient with a recurrent GBM after treatmentby intranasal delivery of POH, is mediated by apoptosis. Result: Data from classical histology, terminaldeoxynucleotidyl-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) assay, as well asactivation of caspase 3, showed increased apoptosis in the treated tumor. Conclusion: These findings suggest that strategies to inactivate EGFR and RAS signaling may be critical to improving not only theefficacy of single-agent therapy but also of multimodal therapy in gliomas.

Temozolomide Chemotherapy in Patients with Recurrent Malignant Gliomas

Numerous studies have demonstrated the clinical activity of temozolomide, a second-generation alkylating agent, against malignant brain tumors, however, its activity has not been reported in an Asian population. This study analyzed the efficacy and toxicity of temozolomide in 25 adult patients with recurrent or progressive malignant gliomas after surgery and standard radiation therapy with or without chemotherapy, enrolled in our institution since July 2000. Sixteen patients had glioblastoma multiforme (GBM), six with anaplastic astrocytoma, and three with anaplastic oligodendroglioma. Of the 25 patients, 3 (12%) achieved a complete response (CR), 8 (32%) achieved a partial response (PR), 6 (24%) had stable disease (SD), and 8 (32%) had progressive disease (PD). Two patients achieved a CR, 4 patients achieved a PR, 3 patients had SD and 7 patients had PD in GBM, and 1 patient achieved a CR, 4 patients achieved a PR, 3 patients had SD, 1 patient had PD in the non-GBM patients. Median progression free survival was 8 weeks in GBM and 22 weeks in the non-GBM patients. The median overall survival of each group was 17 weeks and 28 weeks. Temozolomide demonstrated moderate activity in recurrent and progressive malignant gliomas without serious toxicity.

Sheep erythrocyte demonstrated better effect than IL-2 and IFN-gamma as biological response modifier against glioma in experimental model.

The significant insights into the immunobiology of central nervous system (CNS) and brain tumor have opened up the feasibility of applying 'Immunotherapy' as an alternative to the poor prognosis of malignant brain tumor with conventional therapeutic approaches. Though cytokines like IL-2 and IFN-gamma used against glioma showed some favorable results by eliciting Th1 type immune response, a proper immunotherapeutic agent is still to be searched for. Sheep erythrocyte (SRBC), a corpuscular antigen showed a better therapeutic efficacy in terms of enhanced survival and augmentation of cell mediated immunity (CMI) in a glioma model developed by chemical carcinogen ethyl nitrosourea. Histological findings revealed most efficient glioma rejection in SRBC and combination biological response modifier (BRM) treated groups. Simultaneously E-rosetting, cytotoxicity of lymphocytes, phagocytosis and antigen presenting capacity of myeloid cells established the better therapeutic efficacy of SRBC alone than other BRMs viz. IL-2 and IFN-gamma. Even the effect of combination therapy of different BRMs showed marginal differences in facilitating glioma reduction than the single use of SRBC. These findings emphasized the application of SRBC as an exogenous BRM having the potential as a rational therapeutic adjunct against glioma.

Reporte de un caso de la sesión de casos clínicos de la Asociación de Costarricense de Ciencias Neurológicas: sesión del 17 de mayo del 2000 / Report one case of the sesion clinics cases of the Asociación de Costarricense de Ciencias Neurológicas: sesion of 17 may 2000

Los autores reportan el caso de un paciente de 68 años de edad que presentó un episodio de crisis convulsiva contínua del miembro inferior derecho. La resonancia magnética demostró múltiples lesiones en ambos hemisferios cerebrales, especialmente en el lado izquierdo. Una de las lesiones presentaba una imagen de anillo cerrado que se acentuaba con contraste. El paciente presentó varios episodios de déficits focales posteriormente. Las pruebas de HIV, sífilis, toxoplasmosis y cistercosis resultaron negativas, el LCR fue normal y no se encontró fuente embolígena ni neoplásica. Una biopsia cerebral por aguja estableció el diagnóstico de glioma multicéntrico. Palabras clave: glioma multicéntrico, neuroimágenes, crisis convulsiva

Masteidectomia minima: nueva variante del abordaje presigmoideo / Minimal mastoidectomy: a new variation of the presigmoid approach

Los abordajes a la patología de la región petroclival han aumentado en complejidad con el desa-rrollo de nuevas técnicas para la cirugía en base de cráneo. Entre ellas el abordaje presigmoideo retro-laberíntico es el que ha tenido mayor aceptación debido a la amplitud de exposición sumado a la baja morbilidad. Aun siendo baja su morbilidad esta puede ser de importancia debido a la necesidad de exponer el nervio facial, los canales semícirculares y el bulbo de la yugular. Para comprobar si efectivamente es necesario arriesgar dichas estructuras para exponer la región petroclival se diseñó en el laboratorio una variante del abordaje pre-sigmoideo pero con mastoidectomia minima en la cual las mismas permanecían indemnes. Fueron utilizadas diez cabezas cadavérícas y cinco cráneos a los efectos de comparar ambos abordajes. Curiosamente observa-mos que la mastoidectomia minima ofreció el mismo angulo de exposición así como similar cercanía a la región petroclival comparado con la variante retrolaberíntica pero sin la morbilidad que significa exponer las estructuras neurovasculares y otológicas escondidas en la profundidad del hueso temporal, Futuras pruebas clínicas utilizando esta nueva variante del abordaje presigmoideo aclararan su real valor en la resolución de las lesiones ubicadas en la región petroclival.

Evolución de 157 pacientes con gliomas de diferente grado de malignidad sometidos a tratamiento multidisciplinario / Evolution of 157 patients whith gliomas of different degree malignity with multidisplinary treatment

Se analiza la evolución de 157 pacientes (97 varones) con diagnóstico histológico de astrocito-ma anaplásico (AA, N=53), astrocitoma de bajo grado (ABG, N=31) y glioblastoma (GB, N=73) sometidos a tratamiento multidisciplinario. Los pacientes con AA, GB y ABG con resecciones parciales (RP) o recidiva realizaron cirugía, radioterapia y/o quirnioterapia (lomustina, vincristina y procarbazina). Los ABG con resec-ción completa (RC) efectuaron solo cirugia. La edad X ñ ES fue 49,71 ñ 1,9 para AA, 39,19 ñ 2,4 para ABG y 59,13 +- 1,3 para GB (p < 0,0001). Un Karnofsky > 70 por ciento se observó en el 84,90 por ciento, AA, 90,32 por ciento ABG y 38,35 por ciento GB. El número de RC fue: 64,15 por ciento para AA; 61,29 por ciento ABG y 23,28 por ciento GB. Se encontraron diferencias significativas entre la edad, Karnofsky y tipos de cirugía de los distintos tipos histológicos. La sobrevida media para AA fue 30,02 meses (IC 95 por ciento 25,99 - 34,05); 43,32 meses (IC 95 por ciento, 36.82 - 49,83) para ABG y 10,20 meses (IC 95 por ciento, 9,28 - 11,12) para GB. La sobrevida se correlacionó con edad, Karnofsky y tipo de cirugía (p<0.0001) en pacientes AA y con Karnofsky en pacientes GB (p<0,000 l). Cuando se analizó la sobrevida de los diferentes tipos histológicos en función de la cirugia y Karnofsky se observó rnayor sobrevida en los pacientes con RC y Karnofskv > 70 por ciento (p<0,0001, Log rank test). Sólo en 10 pacientes la toxicidad correspondió al grado 3 de la OMS y ninguin caso requirió modificación de la dosis. En concordancia con otras comunicaciones la evolución de los AA fue mejor que la de los GB. La mayor frecuencia de resecciones completas, el mejor Karnofsky y la menor edad pueden contribuir con estos resultados. La mejor evolución de los pacientes con ABG dependería más del tipo histológico que de las otras variables consideradas.

Tumores do sistema nervoso central / Tumors of the central nervous system

A autora destaca a importância dos tumores do sistema nervoso central em Pediatria, visto tratar-se do segundo grupo de neoplasias em frequência. Estuda os gliomas de alto e baixo grau de malignidade, os astrocitomas cerebelares, gliomas supratentoriais e de linha média, de vias ópticas e do tronco cerebral, o meduloblastoma e os tumores da regiäo pineal, analisando seu quadro clínico, diagnóstico, evoluçäo e tratamento