Genomic analysis in the practice of surgical neuropathology: The emory experience

The evaluation of central nervous system tumors increasingly relies on molecular genetic methods to aid in classification, offer prognostic information, and predict response to therapy. Available assays make it possible to assess genetic losses, amplifications, translocations, mutations, or the expression levels of specific gene transcripts or proteins. Current molecular diagnostics frequently use a panel-based approach and whole genome analysis, and generally rely either on DNA sequencing or on hybridization- based methodologies, such as those used in cytogenomic microarrays. In some cases, immunohistochemistry can be used as a surrogate for genetic analysis when the mutation of interest consistently results in overexpression or underexpression of a known protein product. In surgical neuropathology practice, the diagnostic workup of diffuse gliomas, medulloblastomas, low-grade circumscribed gliomas, as well as other diseases, now routinely incorporates the results of genomic studies. Here we summarize our institution's current approach to diagnostic surgical neuropathology, using these contemporary molecular diagnostic applications.