Posterior fossa tumor in children

Primary brain tumors are the most common solid neoplasms of childhood, representing 20% of all pediatric tumors. The best current estimates place the incidence between 2.76 and 4.28/100,000 children per year. Compared with brain tumors in adults, a much higher percentage of pediatric brain tumors arise in the posterior fossa. Infratentorial tumors comprise as many as two thirds of all pediatric brain tumors in some large series. Tumor types that most often occur in the posterior fossa include medulloblastoma, ependymoma, cerebellar astrocytoma and brainstem glioma. All pediatric cases of posterior fossa tumor that were considered for surgery from 1981 to 2011 were selected and the demographic data including age, gender and tumor characteristics along with the location and pathological diagnosis were recorded. The surgical outcomes were assessed according to pathological diagnosis. Our series consisted of 84 patients [52 males, 32 females]. Cerebellar symptoms were the most common cause of presentation [80.9%] followed by headache [73.8%] and vomiting [38.1%]. The most common histology was medulloblastoma [42.8%] followed by cerebellar astrocytoma [28.6%], ependymoma [14.3%], brainstem glioma [7.2%] and miscellaneous pathologies [e.g., dermoid, and tuberculoma] [7.2%]. The diagnosis of brain tumors in the general pediatric population remains challenging. Most symptomatic children require several visits to a physician before the correct diagnosis is made. These patients are often misdiagnosed for gastrointestinal disorders. Greater understanding of the clinical presentation of these tumors and judicious use of modern neuroimaging techniques should lead to more efficacious therapies

Surgical outcome of posterior fossa epidermoid tumors [1980-2008]

Epidermoid tumors comprise 5% of posterior fossa tumors and are the third among tumors of the cerebellopontine region in frequency. In the review of recent literature, there are several case reports but few case series. In this retrospective study, we evaluated the surgical results of our patients, reviewed the existing literature and compared our results with other series. Surgical results of 8 patients with epidermoid tumor that originated mostly in the posterior fossa from 1980-2008 in Mehrad Hospital, in Tehran, are presented. The age, sex, duration, signs and symptoms, topographical location, surgical approach, the extent of resection and outcome are analyzed and compared with other series. This study is based on the clinical data of 8 patients operated from 1980-2008 in Mehrad Hospital, in Tehran, due to posterior fossa epidermoid tumors. 62.5% of the patients were female. The average age of our patients were 34.1 years [range: 2453 years]. The most common symptom was headache [87.5%]. The most common tumor location was cerebellopontine angle. Supratentorial extension was observed in half of our patients. In 37.5% of the cases, the tumor was resected totally. The mean followup period was 31.5 months [range: 1-115 months]. In the post operative period, 37.5% of our patients suffered from complicating events, but we had no mortality in our series. In contrast with other posterior fossa benign tumors, in which the cure is obtained by overcoming surgical technical difficulties, the main problems in the management of epidermoids remain misdiagnosis, incomplete removal at the first operation, and delayed detection of recurrences. With the use of modern microneurosurgical techniques, our surgical results are comparable with other series. Extended multicentric prospective studies are recommended for more definitive results

Ganglioneuroblastoma of the cerebellum: neuroimaging and pathological features of a case

OBJECTIVE: To report a case of ganglioneuroblastoma of cerebellum, with emphasis to the neuroimaging and pathological findings. CASE REPORT: A one year and eight-month-old girl presented with a two-month history of hypoactivity and tremor in the legs. The MRI showed an enhancing cerebellar mass hypointense on T1 and hyperintense on T2-weighted images. The patient underwent a craniotomy with resection of the lesion. The histological and immunohistochemical studies defined the diagnosis of ganglioneuroblastoma. CONCLUSION: The MRI findings of our case showed no features which could help in the differentiation between ganglioneuroblastoma and the other common types of posterior fossa neoplasms in the pediatric population.

OBJETIVO: Relatar um caso de ganglioneuroblastoma no cerebelo, com ênfase aos achados de imagem e patologia. RELATO DO CASO: Paciente feminino de um ano e oito meses apresentou-se com hipoatividade e tremor nas pernas há dois meses. A RM demonstrou uma massa cerebelar hipercaptante, com hipossinal em T1 e hipersinal em T2. A paciente foi submetida a craniotomia com ressecção da lesão. Os exames histológicos e imuno-histoquímicos definiram o diagnóstico de ganglioneuroblastoma. CONCLUSÃO: Os achados de RM deste caso não demonstraram padrões que pudessem auxiliar na diferenciação entre ganglioneuroblastoma e os demais tumores que comumente acometem a fossa posterior de crianças.

Diagnóstico tomográfico de los tumores endocraneales / Computed tomographic evaluation of brain neoplasms

De 14.386 estudios tomográficos realizados entre enero de 1989 y junio de 1992, 7.146 fueron de cerebro. Dentro de este grupo, 390 pacientes presentaron patología tumoral encefálica. De 130 pacientes se obtuvo confirmación histológica del tumor, correlacinando los datos obtenidos de acuerdo a edad, sexo y localización de la lesión y las variantes histológicas halladas