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  • Impact of EGFR genetic variants on glioma risk and patient outcome
    Publication . Costa, BM; Viana-Pereira, M; Fernandes, R; Costa, S; Linhares, P; Vaz, R; Pinheiro, C; Lima, J; Soares, P; Silva, A; Pardal, F; Amorim, J; Nabiço, R; Almeida, R; Alegria, C; Pires, MM; Pinheiro, C; Carvalho, E; Oliveira, P; Lopes, JM; Reis, RM
    BACKGROUND: The epidermal growth factor receptor (EGFR) regulates important cellular processes and is frequently implicated in human tumors. Three EGFR polymorphisms have been described as having a transcriptional regulatory function: two single-nucleotide polymorphisms in the essential promoter region, -216G/T and -191C/A, and a polymorphic (CA)(n) microsatellite sequence in intron 1. We aimed to elucidate the roles of these EGFR polymorphisms in glioma susceptibility and prognosis. METHODS: We conducted a case-control study with 196 patients with glioma and 168 cancer-free controls. Unconditional multivariate logistic regression models were used to calculate ORs and 95% confidence intervals. A Cox regression model was used to evaluate associations with patient survival. False-positive report probabilities were also assessed. RESULTS: None of the EGFR -216G/T variants was significantly associated with glioma risk. The -191C/A genotype was associated with higher risk for glioma when the (CA)(n) alleles were classified as short for ≤16 or ≤17 repeats. Independently of the (CA)(n) repeat cutoff point used, shorter (CA)(n) repeat variants were significantly associated with increased risk for glioma, particularly glioblastoma and oligodendroglioma. In all tested models with different (CA)(n) cutoff points, only -191C/A genotype was consistently associated with improved survival of patients with glioblastoma. CONCLUSIONS: Our findings implicate EGFR -191C/A and the (CA)(n) repeat polymorphisms as risk factors for gliomas, and suggest -191C/A as a prognostic marker in glioblastoma. IMPACT: Our data support a role of these EGFR polymorphisms in determining glioma susceptibility, with potential relevance for molecularly based stratification of patients with glioblastoma for individualized therapies
  • Primary spinal glioblastoma: A case report and review of the literature
    Publication . Morais, N; Mascarenhas, L; Soares- Fernandes, JP; Silva, A; Magalhães, Z; Moreira da Costa, JA
    Primary spinal glioblastoma (GBM) is a rare disease, with an aggressive course and a poor prognosis. We report a case of a 19-year-old male with a 4-week history of progressive weakness in both lower limbs, which progressed to paraparesis with a left predominance and difficulty in initiating urination over a week. Spine magnetic resonance imaging (MRI) showed an intramedullary expansile mass localised between T6 and T11. We performed a laminotomy and laminoplasty between T6 and T11 and the tumour was partially removed. Histopathological study was compatible with GBM. The patient was administered focal spine radiotherapy with chemotherapy with temozolamide. Serial MRI performed after the initial surgery demonstrated enlargement of the enhancing mass from T3 to T12 and subarachnoid metastatic deposits in C2 and C4, the pituitary stalk, interpeduncular cistern, left superior cerebellar peduncle and hydrocephalus. We review the literature with regard to the disease and treatment options, and report the unique features of this case. Primary spinal GBM is an extremely rare entity with a poor prognosis and a short survival time. An aggressive management of the different complications as they arise and improvement of current modes of treatment and new treatment options are required to improve survival and ensure better quality of life.
  • Um final feliz: causa rara de hipotonia cervical em lactente
    Publication . Sampaio, B; Silva, A; Costa, JA; Pereira, A; Silva, H
  • Primary angiitis of the central nervous system: an infrequent form of presentation
    Publication . Jordão, MJ; Almeida, F; Moreira da Costa, JA; Rocha, J
    INTRODUCTION: Primary angiitis of the central nervous system (CNS) is a rare disease. Clinical signs and symptoms include headache and cognitive disorders associated to multifocal neurological deficits. A definitive diagnosis can only be achieved by means of a cerebromeningeal biopsy. CASE REPORT: We describe the case of a 15-year-old male who first reported lower back pain and progressive paresis of the right lower limb, later followed by laterocollis on the right side. Magnetic resonance (MR) scanning of the brain and spinal cord revealed a pseudotumoral lesion in the right cerebellum and two lesions in the spinal cord. Dexamethasone was administered and surgical resection of the cerebellar lesion was performed. Following surgery, the patient received corticoid treatment with progressive withdrawal. Full clinical recovery of the patient was achieved. A year later, the same patient was admitted to hospital again because of headaches and diplopia. A new MR brain scan showed a right frontotemporal lesion. Dexamethasone was administered and the patient recovered. Thirteen months later, he reported dysarthria and right-side hemiparesis. An MR brain scan revealed the presence of a number of bilateral lesions in the white matter. Results of a lumbar puncture showed lymphocytic pleocytosis and raised protein levels in cerebrospinal fluid. The laminae from the cerebromeningeal biopsy were reviewed and the results confirmed the hypothetical diagnosis of angiitis of the CNS. Treatment was established with intravenous cyclophosphamide in association with oral prednisone. CONCLUSIONS: Primary angiitis of the CNS is an infrequent disease and its pathogenesis remains unknown. The definitive diagnosis of these patients is histological. It courses spontaneously and generally has a fatal outcome. Treatment, which consists in an association of cyclophosphamide and prednisone, must be started as early as possible.
  • Primary Bilateral Thalamic Astrocytoma Presenting With Head Tremor, Ataxia, and Dementia
    Publication . Machado, A; Ribeiro, M; Rodrigues, M; Ferreira, C; Almeida, R; Santana, I; Castro, L; Carpenter, S
  • Prognostic value of MGMT promoter methylation in glioblastoma patients treated with temozolomide-based chemoradiation: a Portuguese multicentre study
    Publication . Costa, BM; Caeiro, C; Guimarães, I; Martinho, O; Jaraquemada, T; Augusto, I; Castro, l; Osório, L; Linhares, P; Honavar, M; Resende, M; Nabiço, R; Almeida, R; Alegria, C; Pires, M; Pinheiro, C; Carvalho, E; Lopes, JM; Costa, P; Damasceno, M; Reis, RM
    Glioblastoma (GBM) is the most common and aggressive primary brain tumor. The identification of novel molecular prognostic markers of GBM has recently been an area of great interest in neuro-oncology. The methylation status of the MGMT gene promoter is currently a promising molecular prognostic marker, but some controversial data have precluded its clinical use. We analyzed MGMT methylation by methylation-specific PCR in 90 GBM patients from four Portuguese hospitals, uniformly treated with radiotherapy combined with concomitant and adjuvant temozolomide (Stupp protocol). The Kaplan-Meier method was used to construct survival curves, and the log-rank test and a Cox-regression model were used to analyze patient survival. The methylation status of MGMT was successfully determined in 89% (80/90) of the tumors. The frequency of tumoral MGMT promoter methylation was 47.5%. The median overall survivals (OSs) were 16 months (95% CI 12.2-19.8) and 13 months (95% CI 13.3-18.7) for patients whose tumors had a methylated or unmethylated MGMT, respectively. Univariate and multivariate analyses did not show any statistically significant association between MGMT methylation status and patient OS (P=0.583 by the log-rank test; P=0.617 by the Cox-regression test) or progression-free survival (P=0.775 by the log-rank test; P=0.691 by the Cox-regression test). None of the patient clinical features were significantly correlated with survival. This is the first study to report the frequency of MGMT methylation among Portuguese GBM patients. Our data did not show statistically significant associations between MGMT promoter methylation and the outcome of GBM patients treated with temozolomide. Additional robust prospective studies are warranted to clarify whether the MGMT status should be used in clinical decisions.
  • Abcesso isolado do clivus achados em ressonância magnética convencional: estudo de difusão
    Publication . Fernandes, JS; Valle, JM; Morais, N; Ribeiro, M; Magalhães, Z; Moreira da Costa, JA; Rocha, J