Systemic dissemination of glioblastoma: literature review

SUMMARY INTRODUCTION: Glioblastoma (GBM) is the most frequent primary malignant tumor from the central nervous system in adults. However, the presence of systemic metastasis is an extremely rare event. The objective of this study was to review the literature, evaluating the possible biological mechanisms related to the occurrence of systemic metastasis in patients diagnosed with GBM. RESULTS: The mechanisms that may be related to GBM systemic dissemination are the blood-brain barrier breach, often seen in GBM cases, by the tumor itself or by surgical procedures, gaining access to blood and lymphatic vessels, associated with the acquisition of mesenchymal features of invasiveness, resistance to the immune mechanisms of defense and hostile environment through quiescence. CONCLUSIONS: Tumor cells must overcome many obstacles until the development of systemic metastasis. The physiologic mechanisms are not completely clear. Although not fully understood, the pathophysiological understanding of the mechanisms that may be associated with the systemic spread is salutary for a global understanding of the disease. In addition, this knowledge may be used as a basis for a therapy to be performed in patients diagnosed with GBM distant metastasis.

RESUMO INTRODUÇÃO: Glioblastoma (GBM) é o tumor maligno mais comum do sistema nervoso central em adultos. Entretanto, metástase a distância de GBM é um evento extremamente raro. O presente estudo teve o objetivo de realizar uma revisão da literatura para avaliar os possíveis mecanismos biológicos relacionados com a ocorrência de metástase a distância de pacientes com diagnóstico de GBM. RESULTADOS: Os mecanismos que podem estar relacionados com a capacidade de disseminação sistêmica do GBM são a quebra de barreira hematoencefálica (BHE) frequentemente vista em GBM, seja pela doença, seja por procedimentos cirúrgicos, dando acesso aos vasos sanguíneos e linfáticos, associada à aquisição de características mesenquimais de invasividade, resistência aos mecanismos de defesa do sistema imunológico e adaptação a hostilidades dos meios distantes por meio de quiescência. CONCLUSÕES: As células tumorais necessitam vencer diversos obstáculos até a formação de uma metástase distante. Apesar de não totalmente esclarecido, o entendimento fisiopatológico dos mecanismos pelos quais podem estar associados à disseminação sistêmica do GBM é salutar para a compreensão global da doença. Além disso, esse conhecimento pode servir de base para a terapia a ser empregada diante do paciente com diagnóstico de GBM com metástase a distância.

The role of surgery in primary central nervous system lymphomas / El rol de la cirugía en los linfomas primarios del sistema nervioso central

ABSTRACT Background Primary central nervous system lymphomas (PCNSL) are infrequent. The traditional treatment of choice is chemotherapy. Complete resections have generally not been recommended, because of the risk of permanent central nervous system deficits with no proven improvement in survival. The aim of the current study was to compare survival among patients with PCNSL who underwent biopsy versus surgical resection. Methods A retrospective study was conducted on 50 patients with a confirmed diagnosis of PCNSL treated at our center from January 1994 to July 2015. Results Patients in the resection group exhibited significantly longer median survival time, relative to the biopsy group, surviving a median 31 months versus 14.5 months; p = 0.016. Conclusions In our series, patients who had surgical resection of their tumor survived a median 16.5 months longer than patients who underwent biopsy alone.

RESUMO Introducción Los linfomas primarios del sistema nervioso central (LPSNC) son infrecuentes. Tradicionalmente el tratamiento de elección es la quimioterapia. Existe un paradigma de no indicar resección, por el riesgo de déficit neurológico sin aumento de la sobrevida. El objetivo del presente estudio es comparar la sobrevida de pacientes con LPSNC sometidos a biopsia versus resección. Métodos Estudio retrospectivo que incluye 50 pacientes con diagnóstico confirmado de LPSNC tratados en nuestra Institución desde enero de 1994 hasta julio de 2015. Resultados Los pacientes del "grupo resección" mostraron una sobrevida media significativamente mayor respecto a los del "grupo biopsia"; 31 meses versus 14,5 meses respectivamente, p = 0,016. Conclusiones En nuestra serie, los pacientes que con resección quirúrgica de su tumor tuvieron una sobrevida media de 16,5 meses superior que los pacientes biopsiados.

Estudio restrospectivo de 48 casos de linfoma primario del sistema nervioso central / Retrospective study of 48 cases of primary central nervous system lymphoma

Los linfomas primarios del sistema nervioso central (LPSNC) son neoplasias infrecuentes confinadas al SNC. Más del 90% son de tipo B y afectan principalmente a pacientes entre 50-70 años. La inmunodeficiencia es el factor de riesgo más importante. El objetivo de nuestro trabajo fue evaluar las características demográficas, estado inmunológico y los hallazgos en los estudios complementarios de pacientes con LPSNC. Se realizó el análisis retrospectivo de 48 casos estudiados en nuestro centro desde enero 1992 a mayo 2015. La edad mediana de presentación fue 61 años (25-84); la relación hombre:mujer 2.1:1. El 85% (41 casos) fueron inmunocompetentes al momento del diagnóstico. El 94% (45 casos) tuvo compromiso parenquimatoso, 4% (2 casos) meníngeo y 2% (1 caso) ocular. El lóbulo más afectado fue el frontal (43%) y 35% tuvieron compromiso ganglio basal. En RM, el 89% mostró realce con contraste y 55% restricción en difusión. El síndrome piramidal fue la manifestación inicial más frecuente (56%). El LCR fue inflamatorio en el 72%, aunque solo 11.1% presentó examen citológico positivo. El tipo más frecuente de LPSNC fue no-Hodgkin B (96%) y el subtipo difuso de células grandes el más habitual (83%). En nuestra serie la ausencia de inmunocompromiso fue una característica frecuente y la presentación clínico-radiológica fue muy pleomórfica. La sospecha inicial permitiría arribar a un diagnóstico temprano, evitando tratamientos empíricos que puedan confundir o retrasar el diagnóstico.

Primary central nervous system lymphoma (PCNSL) is an infrequent form of non-Hodgkin lymphoma restricted to the CNS. More than 90% are type B and mainly affect patients aged 50-70 years. Immunodeficiency is the most important risk factor. The aim of our study was to evaluate the immune status, clinical presentation and findings in complementary studies of PCNSL patients. A retrospective analysis of 48 cases treated in our center between January 1992 and May 2015 was performed. Median age at diagnosis was 61 years (range 25-84); with male predominance (2.1:1). Forty one cases (85%) were immunocompetent patients. Brain MRI findings showed parenchymal involvement in 45 cases (94%), 43% with frontal lobe and 35% basal ganglia, 4% had meningeal involvement and 2% had ophthalmic involvement at diagnosis. Fifty-five percent had restricted signal on diffusion weighted imaging and contrast enhancement was found in 89%. Pyramidal syndrome was the main initial clinical manifestation (56%). There were abnormal findings in 62% of CSF samples, but in only 11.1% positive cytology results were detected. The most frequent type was diffuse large B-cell lymphoma (83%), being B-cell type the most common form between them (96%). In our series PCNSL was more frequent in immunocompetent elderly male subjects. At initial evaluation, clinical manifestations and MRI findings were variable. The initial suspicion of this entity would allow an early diagnosis, avoiding empirical treatments that may confuse or delay diagnosis.

Immunological alterations in patients with primary tumors in central nervous system

Natural Killer (NK) cells play an important role in immune surveillance against tumors. The present work aimed to study the cytotoxic activity of NK cells and T cell subsets in peripheral blood of 13 patients with primary in central nervous system (CNS). As controls 29 healthy subjects with the age range equivalent to the patients were studied. The methods employed were: a) determination of cytotoxic activity of NK cells towards K562 target cells, evaluated by single cell-assay; b) enumeration of CD3+ lymphocytes and their CD4+ and CD8+ subsets defined by monoclonal antibodies; c) the identification of tumors were done by histologic and immunochemistry studies. The results indicated that adults and children with tumor in CNS display reduced percentage of total T cells, helper/inducer subset and low helper/suppressor ratio. The cutotoxic activity of NK cells was decreased in patients with CNS tumors due mainly to a decrease in the proportion of target-binding lymphocytes. These results suggest that cytotoxic activity of NK cells may be affected by the immunoregulatory disturbances observed in patients with primary tumors in CNS.