| Abstract: | Metastatic brain disease frequently complicates extra central nervous system (CNS) neoplastic disease, with an increase in reported incidence over time. Brain parenchyma is the commonest anatomical site, with other lesions involving the spinal cord, dura and tissues surrounding the CNS. Metastases are usually characterised by a well-defined border with surrounding brain, although some can show an infiltrative edge. The use of appropriate immunohistochemical panels can help identify the origin of most tumours, and molecular testing should be performed according to the site of origin even if performed on a previous specimen due to potential changes in molecular characteristics. Reliable detection of leptomeningeal metastasis using CSF cytology relies on examination of an adequate volume of fluid; immunocytochemistry and flow cytometry can also be useful in the correct settings. Advances in the field include liquid biopsies, where circulating biomarkers are examined, and the use of methylation profiling to identify primary tumours. |
