Medulloblastoma in adults: a series from Brazil

We retrospectively reviewed 15 adult patients (11 males, median age 34 years; range 23-48) who had been treated and followed in our Institution since 1991 from the time of diagnosis until death or last follow-up in December 2001. Headache was the most frequent symptom (93%). the tumor was hemispheric in 11 patients. Complete resection was achieved in eight. CSF in 12 patients and craniospinal MRI in 6 did not show metastatic disease. Two patients refused adjuvant treatment and died with progressive disease. Thirteen patients received adjuvant craniospinal radiotherapy and 11 systemic chemotherapy. After initial treatment only 2 of the 13 patients relapsed in the posterior fossa. Recurrence was probably related to sub-optimal radiotherapy planning: inadequate low dose in the posterior fossa (37.5 Gy) and long delay in initiating treatment. Two of the 13 patients that received adjuvant treatment died: one from meningitis, and one from recurrent disease. Eleven patients remained alive, and disease-free with Karnofsky performance status ranging 80-100. the median overall survival was not reached after a median follow-up of 5.6 years (range 0.7-10.8 years). Estimated 1-, 5- and 10-year overall survival rates were 86.7%, 72.7%, and 72.7%, respectively. Adult medulloblastoma was predominant in males and the majority of patients had hemispheric tumors. Long-term survival was not uncommon. Although chemotherapy may be useful and well tolerated, radiotherapy remains the mainstay adjuvant treatment as suggested by our two recurrences associated with a delay or inadequate dose.Universidade Federal de São Paulo, Dept Neurol, Escola Paulista Med, BR-04023900 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Neurosurg, Escola Paulista Med, BR-04023900 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Pathol, Escola Paulista Med, BR-04023900 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Neurol, Escola Paulista Med, BR-04023900 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Neurosurg, Escola Paulista Med, BR-04023900 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Pathol, Escola Paulista Med, BR-04023900 São Paulo, BrazilWeb of Scienc

Stereotactic biopsy guidance in adults with supratentorial nonenhancing gliomas: role of perfusion-weighted magnetic resonance imaging

Object. the diagnosis of low-grade glioma (LGG) cannot be based exclusively on conventional magnetic resonance (MR) imaging studies, and target selection for stereotactic biopsy is a crucial issue given the high risk of sampling errors. the authors hypothesized that perfusion-weighted imaging could provide information on the microcirculation in presumed supratentorial LGGs.Methods. All adult patients with suspected (nonenhancing) supratentorial LGGs on conventional MR imaging between February 2001 and February 2004 were included in this study. Preoperative MR imaging was performed using a dynamic first-pass gadopentate dimeglumine-enhanced spin echo-echo planar perfusion-weighted sequence, and the tumors' relative cerebral blood volume (rCBV) measurements were expressed in relation to the values observed in contralateral white matter. in patients with heterogeneous tumors a stereotactic biopsy was performed in the higher perfusion areas before resection. Among 21 patients (16 men and five women with a mean age of 36 years, range 23-60 years), 10 had diffuse astrocytomas (World Health Organization Grade II) and 11 had other LGGs and anaplastic gliomas. On perfusion-weighted images demonstrating heterogeneous tumors, areas of higher rCBV focus were found to be oligodendrogliornas or anaplastic astrocytomas on stereotactic biopsy; during tumor resection, however, specimens were characterized predominantly as astrocytomas. Diffuse astrocytomas were associated with significantly lower mean rCBV values compared with those in the other two lesion groups (p < 0.01). the rCBV ratio cutoff value that permitted better discrimination between diffuse astrocytomas and the other lesion groups was 1.2 (80% sensitivity and 100% specificity).Conclusions. Perfusion-weighted imaging is a feasible method of reducing the sampling error in the histopathological diagnosis of a presumed LGG, particularly by improving the selection of targets for stereotactic biopsy.Universidade Federal de São Paulo, Ctr Med Diagnost Fleury, BR-01333391 São Paulo, SP, BrazilUniversidade Federal de São Paulo, Dept Neurol, BR-01333391 São Paulo, SP, BrazilUniversidade Federal de São Paulo, Dept Neurosurg, BR-01333391 São Paulo, SP, BrazilUniversidade Federal de São Paulo, Dept Pathol, BR-01333391 São Paulo, SP, BrazilUniversidade Federal de São Paulo, Ctr Med Diagnost Fleury, BR-01333391 São Paulo, SP, BrazilUniversidade Federal de São Paulo, Dept Neurol, BR-01333391 São Paulo, SP, BrazilUniversidade Federal de São Paulo, Dept Neurosurg, BR-01333391 São Paulo, SP, BrazilUniversidade Federal de São Paulo, Dept Pathol, BR-01333391 São Paulo, SP, BrazilWeb of Scienc