Revision 7 for 'Modified Ringertz grading system for diffuse astrocytomas'All Revisions
Modified Ringertz grading system for diffuse astrocytomas
Unlike the WHO grading system and St Anne-Mayo grading system (also known as the Dumas-Duport grading system) which divide astrocytomas into 4 grades, the Ringertz grading system only has 3 grades, and only applies to diffuse astrocytomas (i.e. not WHO grade 1 tumors such as pilocytic astrocytomas or subependymal giant cell astrocytomas) 1.
As such there is a rough equivalence between WHO II - IV and modified Ringertz I - III, although there are some differences in the criteria required to fulfill various grades.
The modified Ringertz grading system is as follows 2:
- grade 1 = astrocytoma
- roughly equivalent to WHO grade II
- mild hypercellularity
- mild nuclear atypia (nuclear enlargement, hyperchromasia, pleomorphism)
- rare mitotic figures
- grade 2 = anaplastic astrocytoma
- roughly equivalent to WHO grade III
- more cellular than grade 2
- more nuclear atypia
- more mitotic figures
- endothelial proliferation (note this is a WHO grade IV feature)
- grade 3 = glioblastoma
- roughly equivalent to WHO grade IV
- presence of geographic necrosis +/- surrounding pseduopalisading tumor cells
History and etymology
Ringertz originally proposed the grading system in 1950 4.