Anaplastic oligodendroglioma NOS

Dr Jeremy Jones and A.Prof Frank Gaillard et al.

Anaplastic oligodendroglioma NOS (not-otherwise-specified) is a diagnosis in the current (2016) WHO classification of CNS tumours denoting a diffuse infiltrating glioma that has histological features of anaplastic oligodendroglioma, but without 1p19q co-deletion status or IDH mutation status being available (either because the test has not been performed, or the markers are equivocal) 1

It is, therefore, equivalent to the diagnosis of anaplastic oligodendroglioma pre-2016, and it is essential to note that the imaging features of anaplastic oligodendrogliomas defined on histological grounds versus those defined using 1p19q co-deletion and IDH mutation are not identical. These are discussed further in the article on oligodendroglioma

Importantly, neither ATRX status (usually the opposite of 1p19q co-deletion status) nor additional immunohistochemical markers such as NOGO-A are substitutes for formal 1p19q co-deletion determination, and as such unless both IDH mutation and 1p19q co-deletion are assessed, the formal diagnosis of anaplastic oligodendroglioma cannot be made.  

Share article

Article information

rID: 53462
Synonyms or Alternate Spellings:

Support Radiopaedia and see fewer ads

Cases and figures

  • Drag
    Case 1: haemorrhagic
    Drag here to reorder.
  • Drag
    WHO 2016 diffuse glioma classification
    Drag here to reorder.
  • Drag
    Case 2
    Drag here to reorder.
  • Drag
    Case 3
    Drag here to reorder.
  • Drag
    Case 4
    Drag here to reorder.
  • Updating… Please wait.
    Loadinganimation

    Alert accept

    Error Unable to process the form. Check for errors and try again.

    Alert accept Thank you for updating your details.