The term "low-grade gliomas" is used by neurologists and neurosurgeons to describe a group of intrinsic cerebral tumors arising primarily from astrocytes, oligodendrocytes or ependymal cells that are characterized by their relatively slow rate of growth and certain radiological appearances when compared with the commoner malignant or "high-grade" gliomas. The use of the term is often confusing since it is not a precise pathological definition. It is sometimes used to refer only to low-grade astrocy-tomas, but oligodendrogliomas, ependymomas, gangliogliomas and pleomorphic xanthoastro-cytomas will sometimes be included as well. To add to the confusion, the pathology of these various tumors often overlaps, and "mixed oligoastrocytomas" or "ependymal differentiation in an oligodendroglioma", for instance, are quite often reported by pathologists on microscopic examination of biopsy specimens. Furthermore, there is no precise border between "low grade" and "high grade", and many tumors will be found, on histological examination, to contain cells of differing degrees of malignancy. Although "low-grade" tumors typically grow quite slowly, it is euphemistic to describe them as "benign" since the great majority of adults with these "low-grade" tumors will die from the disease within 10 years of the initial diagnosis, irrespective of any treatment that they might have received . Death most frequently occurs as a result of the tumor eventually transforming into a more malignant form (in up to 80% of tumors, according to Russell and Rubinstein ) or occasionally as a result of slow but steady expansion of the tumor without obvious malignant change. Patients with these tumors, therefore, are best seen as suffering from a chronic,
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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.