SOMATIC DEFICIENT MISMATCH REPAIR ASSESSED BY IMMUNOHISTOCHEMISTRY AND CLINICAL FEATURES IN BRAZILIAN GLIOBLASTOMA PATIENTS.

BACKGROUND: Glioblastoma (GBM) is the most frequent primary malignant CNS tumor. Deficient mismatch repair (dMMR) is associated with better prognosis and is a biomarker for immunotherapy. Evaluation of MMR by immunohistochemistry (IHC) is accessible, cost effective, sensitive, and specific. AIM: Our objective was to investigate MMR proteins in adult GBM patients. MATERIALS AND METHODS: We retrospectively analyzed 68 GBM samples to evaluate the proficiency of MMR genes expression assessed by IHC. Clinicopathologic and molecular features were compared in proficient (pMMR) or dMMR. RESULTS: 10 (14.7%) samples showed dMMR, and the most frequent was MSH6 (100%) followed by MSH2, PMS2, and MLH1. We observed heterogeneous expression of dMMR in 5 GBMs. The median overall survival did not differ between pMMR (19.8 months; 0.2-30) and dMMR (16.9 months; 6.4-27.5) (p = 0.31). We observed a significantly higher overall survival associated with gross total resection compared to subtotal resection or biopsy (30.7 vs. 13.6 months, p = 0.02) and MGMT methylated status (29.6 vs. 19.8 months, p = 0.049). At the analysis time, 10 patients were still alive, all in the pMMR group. CONCLUSIONS: Our data demonstrated dMMR phenotype assessed by IHC in an expressive portion of GBM patients, however without significant impact on overall survival.

Association of EGFR c.2073A>T polymorphism with decreased risk of diffusely infiltrating astrocytoma in a Brazilian case-control study.

Epidermal growth factor receptor (EGFR) gene overexpression has been implicated in the development of many types of tumors, including glioblastomas, the most frequent diffusely infiltrating astrocytomas. However, little is known about the influence of the polymorphisms of EGFR on EGFR production and/or activity, possibly modulating the susceptibility to astrocytomas. This study aimed to examine the association of two EGFR promoter polymorphisms (c.-191C>A and c.-216G>T) and the c.2073A>T polymorphism located in exon 16 with susceptibility to astrocytomas, EGFR gene expression and survival in a case-control study of 193 astrocytoma patients and 200 cancer-free controls. We found that the variant TT genotype of the EGFR c.2073A>T polymorphism was associated with a significantly decreased risk of astrocytoma when compared with the AA genotype [sex- and age-adjusted odds ratio 0.51, 95% confidence interval 0.26-0.98]. No association of the two promoter EGFR polymorphisms (or combinations of these polymorphisms) and risk of astrocytomas, EGFR expression or survival was found. Our findings suggest that modulation of the EGFR c.2073A>T polymorphism could play a role in future therapeutic approaches to astrocytoma.

A data mining system for providing analytical information on brain tumors to public health decision makers.

Cancer is the leading cause of death in economically developed countries and the second leading cause of death in developing countries. Malignant brain neoplasms are among the most devastating and incurable forms of cancer, and their treatment may be excessively complex and costly. Public health decision makers require significant amounts of analytical information to manage public treatment programs for these patients. Data mining, a technology that is used to produce analytically useful information, has been employed successfully with medical data. However, the large-scale adoption of this technique has been limited thus far because it is difficult to use, especially for non-expert users. One way to facilitate data mining by non-expert users is to automate the process. Our aim is to present an automated data mining system that allows public health decision makers to access analytical information regarding brain tumors. The emphasis in this study is the use of ontology in an automated data mining process. The non-experts who tried the system obtained useful information about the treatment of brain tumors. These results suggest that future work should be conducted in this area.

[Diffuse bone marrow metastasis in cerebellar high-grade astrocytoma. A case report]. / Metastasis difusa de la medula osea en un astrocitoma cerebeloso de alto grado. Un caso clinico.

INTRODUCTION: Cerebellar high-grade astrocytoma is uncommon. Although more prone to present cerebrospinal fluid dissemination, the cerebellar location is not particularly related to the occurrence of extra-cranial metastases, which are also unusual in supratentorial malignant gliomas. CASE REPORT: A 46 year-old man with cerebellar anaplastic astrocytoma who developed pancytopenia due to extensive bone marrow metastases. CONCLUSION: Extraneural metastases of brain gliomas are rare and the spread to the bone marrow confers an extremely poor prognosis for these patients. The expected improvement in glioma patients' survival due to the combination of more efficient therapies may lead to an increased incidence of this uncommon presentation, justifying a more rigorous follow-up of systemic manifestations.

Transcranial Doppler assessment of cerebral blood flow: effect of cardiac transplantation.

The authors prospectively studied transcranial Doppler changes in patients with refractory congestive heart failure before and after cardiac transplantation. They evaluated 22 patients preoperatively and 14 patients after transplantation. Mean postoperative flow velocity increased by 53.3% (p < 0.0001). Preoperative waveform changes became normal after transplantation.

MRI of medulloblastoma in adults.

Medulloblastoma has variable appearances on MRI in both children and adults. Adults are more likely to have heterogeneous cerebellar hemisphere tumours, and this is thought to be related to the greater prevalence of desmoplastic tumours in adulthood. Few studies have addressed the MRI features of adult medulloblastoma and the specific characteristics of desmoplastic and classic tumours have not been analysed. Our aim was to analyse the imaging characteristics of desmoplastic (DM) and classic (CM) medulloblastomas in adult. We retrospectively studied preoperative MRI of six men and three women, median age 33 years, range 23-53 years, with pathologically proved medulloblastomas. There were six (67%) with DM. The tumour was in the cerebellar hemisphere in eight patients (89%), including the three with CM, one of which was bilateral. All tumours were heterogeneous, giving predominantly low or isointense signal on T1- and isointense signal on T2-weighted images. Cystic or necrotic areas in all patients were particularly visible on T2-weighted images. Contrast enhancement was absent in one DM and varied from slight to intense in eight (three CM), homogeneous in one DM and patchy in seven. All tumours extended to the surface of the cerebellum and two had well-defined margins. MRI does not allow a clear distinction between DM and CM in adults.

Avaliaçäo da flebografia orbitária em oito casos de síndrome de Tolosa-Hunt / Orbital phlebography evaluation in 8 cases of Tolosa-Hunt syndrome

A Síndrome de Tolosa-Hunt (STH) ou oftalmoplegia dolorosa é associada a granulomatose inespecifica de etiologia desconhecida que acomete a fissura orbitária superior. Compromete estruturas nervosas e vasculares causando quadro clínico variável que sempre se associa a dor e apresenta resposta favorável à corticoterapia. Processos inflamatório, tumores e anmeurismas dessa regiäo podem causar sintomas semelhantes. A tomografia computadorizada, a angiografia cerebral e a flebografia orbitária säo métodos de imagem indicados para orientar o diagnóstico. Revisamos os resultados destes exames radiológicos de oito pacientes atendidos no Hospital Säo Paulo no período 1989 a 1991, com diagnóstico de STH segundo os critérios de Hunt e Hannerz. A análise das alteraçöes da flebografia orbitária, de acordo com a sistematizaçäo feita por Hannerz e col. Mostrou ser este exame inespecífico, porém capaz de orientar melhor mo diagnóstico

Actinomicose do sistema nervoso central: uma rara complicaçäo da actinomicose cervicofacial / Actinomycosis of the central nervous system: a rare complication of cervicofacial actinomycosis

A actinomicose do sistema nervoso central (SNC) é afecçäo rara, caracterizada pela formaçäo de absesso único e de evoluçäo crônica. Os autores descrevem o caso de um paciente jovem, imunocompetente, com actinomicose cerebral oriunda de foco primário cervicofacial, submetido a ressecçäo cirúrgica e antibioticoterapia. Ressalta-se a importância do conhecimento da entidade e de suas principais formas de acometimento, como a base do diagnóstico precoce dessa enfermedade potencialmente curável e de bom prognóstico