CDKN2A and malignant glioma: The present meta-analysis had two aims: (1) to investigate the clinical prevalence of CDKN2A/B deletions and the impact of CDKN2A/B deletions on OS in all reported series of malignant gliomas and (2) to precisely assess the test accuracy of p16 immunohistochemistry (IHC) for indirect CDKN2A/B detection from all reported series so far.