The correlation between 1p19q status and various biomarkers in selected CNS tumors

Until recently, the diagnosis and classification of brain tumors were based on morphology and immunohistochemical staining findings. Accordingly, morphologically similar tumors were named under a single heading and similar treatment protocols were applied. In 2016, with the changes in the World Health Organization (WHO) classification system, new biomarkers were introduced in the naming and classification of tumors. Thus, the diagnosis, treatment and prognosis of glial tumors have come a long way and studies are still ongoing. Today, genetic aberrations are used in the diagnosis, classification, grading, and determination of treatment options for glial tumors. IDH mutations and 1p/19q co-deletion are the main biomarkers used in the nomenclature of glial tumors. In addition, ATRX, TERT, MGMT and many other biomarkers are used to determine both diagnosis and treatment protocols. Detection of 1p19q co-deletion directly diagnoses oligodendroglioma. However, as we found in our study, 1p19q co-deletion can also be detected in glial tumors with different characteristics and behaviors such as glioblastoma. This suggests that the etiopathogenesis and molecular identification of glial tumors may still have room for improvement.