Grading System
Article
St. Anne-Mayo astrocytoma grading system
Dr Jeremy Jones and Dr Frank Gaillard et al.
The St Anne-Mayo grading system (also known as the Dumas-Duport grading sustem) introduced in 1988 is one of the more popular systems for grading diffuse astrocytomas 1-3.
It is a 4 tiered system (like the WHO grading system) and uses the presence of 4 morphologic criteria to assign a grade: 1. nuclear atypia 2. mitosis 3. endothelial proliferation-'piled-up' endothelial cells. NOT hypervascularity 4. necrosis
The grade then depends on accumulation of these criteria as follows: * grade 1 - 0 criteria * grade 2 - 1 criterion (usually nuclear atypia) * grade 3 - 2 criteria (usually nuclear atypia and mitosis) * grade 4 - 3 or 4 criteria
source: http://radiopaedia.org/articles/st-anne-mayo-astrocytoma-grading-system
Article
WHO grading system for diffuse astrocytomas
Dr Frank Gaillard et al. The WHO grading system is the most widely used system for grading diffuse astroctyomas. Grade I is reserved for localised astrocytomas (see WHO classification of CNS tumours for a complete list) and as such diffuse astrocytomas range in grade from grade II to IV. * Grade II: low grade infiltrative astrocytoma * cellular atypia only * Grade III: anaplastic astrocytoma * increased mitotic activity * cellular anaplasia * Grade IV: glioblastoma * vascular proliferation * necrosis typically with perinecrotic palisading
Gliomatosis cerebri does not have its own grade, but rather is a highly infiltrative version of a low grade or anaplastic tumour which involves at least three lobes 5. It does however confer a worse prognosis.
It is worth noting that there are other grading systems (see diffuse astrocytoma grading) and the pros and cons of each have been the subject of extensive debate.
Source:
St. Anne-Mayo astrocytoma grading system
Dr Jeremy Jones and Dr Frank Gaillard et al.
The St Anne-Mayo grading system (also known as the Dumas-Duport grading sustem) introduced in 1988 is one of the more popular systems for grading diffuse astrocytomas 1-3.
It is a 4 tiered system (like the WHO grading system) and uses the presence of 4 morphologic criteria to assign a grade: 1. nuclear atypia 2. mitosis 3. endothelial proliferation-'piled-up' endothelial cells. NOT hypervascularity 4. necrosis
The grade then depends on accumulation of these criteria as follows: * grade 1 - 0 criteria * grade 2 - 1 criterion (usually nuclear atypia) * grade 3 - 2 criteria (usually nuclear atypia and mitosis) * grade 4 - 3 or 4 criteria
source: http://radiopaedia.org/articles/st-anne-mayo-astrocytoma-grading-system
Article
WHO grading system for diffuse astrocytomas
Dr Frank Gaillard et al. The WHO grading system is the most widely used system for grading diffuse astroctyomas. Grade I is reserved for localised astrocytomas (see WHO classification of CNS tumours for a complete list) and as such diffuse astrocytomas range in grade from grade II to IV. * Grade II: low grade infiltrative astrocytoma * cellular atypia only * Grade III: anaplastic astrocytoma * increased mitotic activity * cellular anaplasia * Grade IV: glioblastoma * vascular proliferation * necrosis typically with perinecrotic palisading
Gliomatosis cerebri does not have its own grade, but rather is a highly infiltrative version of a low grade or anaplastic tumour which involves at least three lobes 5. It does however confer a worse prognosis.
It is worth noting that there are other grading systems (see diffuse astrocytoma grading) and the pros and cons of each have been the subject of extensive debate.
Source: