Of all the tumor-related variables that have been analyzed for their prognostic significance, the histopathological grade, which integrates various specific histological features such as mitotic activity and anaplasia, shows the most profound influence on outcome. Other tumor variables, including tumor volume and location, molecular genetic alterations, gene expression patterns, and proliferation and apoptotic indices do not consistently show such an association with outcome. For example, while aberrant p53 function clearly plays an important role in gliomagenesis and malignant progression, the mutational status of p53 has not been convincingly shown to independently predict prognosis.
Similarly, indices of tumor proliferation or cell death (apoptosis) alone have not been shown to predict outcome consistently for patients with HGG. However, in a few studies attempting to estimate net cell production, apoptotic/prolifer-ative ratios have shown predictive significance for outcome. Currently, the only example of a molecular genetic abnormality that has been consistently shown to correlate with survival and treatment response is the predictive value of 1p and 19q deletions for anaplastic oligoden-droglioma, which, in the most favorable group, showed median survivals from diagnosis of greater than 123 months compared with 16 months for the least favorable group that lacked the 1p deletion (Fig. 10.3) . It is likely that more general variables such as tumor grade and clinical status are better prognostic indicators than are individual tumor features, since they represent the biological summation of individual tumor and molecular variables. However, larger controlled studies may achieve statistical power to identify specific molecular features or profiles that reliably predict patient outcomes or even treatment response.
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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.