Approximately 10% of childhood brain tumors are ependymomas . This tumor is most frequent in young children, with approximately half of the cases occurring before age 5 years. This tumor type appears to be approximately twice as common in males as in females, with an incidence rate of approximately 3.5 per million amongst males and 1.8 per million amongst females. Histologically, ependymomas are composed predominantly of neoplastic ependymal cells, where there is great variability of morphologic appearance. The WHO grading system recognizes four tumor types: subependy-moma and myxopapillary ependymoma (Grade I tumor), low-grade ependymoma (Grade II tumor) and anaplastic ependymoma (Grade III tumor) . However, there is great variability in the classification of ependymomas within these grades and the recognition of the malignant variant is not easily reproducible. Reports in the literature in terms of frequency of the anaplastic variant show wide variation. Several reports using the WHO classification had failed to link poor histologic grade with poor outcome. Thus, the prognostic significance of histology in ependymoma remains unclear.
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The term vaginitis is one that is applied to any inflammation or infection of the vagina, and there are many different conditions that are categorized together under this ‘broad’ heading, including bacterial vaginosis, trichomoniasis and non-infectious vaginitis.