Diffuse astrocytoma grading
Updates to Article Attributes
Diffuse astrocytomas can be graded Grading of diffuse astrocytic tumours in adultsin has been done according to a number of systems over the years, the although by far the most popular now being the WHO grading system. In general
Historically these grading systems focusfocused on the presence or absence of a number of histological features, although more recently genetic/molecular markers have been introduced into the grading schema 3,6:
Histological features historically used include:
- cellular atypia/anaplasia
- mitotic activity
- microvascular proliferation
- necrosis typically with
perinecroticperinecrotic palisading
The most commonly used gradingClassification systems areinclude:
- WHO grading system (most common)
- St.Anne-Mayo grading system
- Kernohan grading system
- Modified Ringertz grading system
Direct equivalence between the grades of various grading systems is of course not possible (otherwise they wouldn't be different systems), and thus care should be taken to state which system is being used and, in some situations, which edition; for example, the 5th edition (2021) WHO classification of CNS tumours suggests prefacing the grade by "WHO CNS" 4,6.
It should be noted that it is well recognised that pathological pathological classification has a high high interobserver variation and and thus imperfectly predicts clinical outcomes 5.
Recent studies have shown that the genetic status of these tumours are more reflective of their subtypes than the histologic grading (please refer on isocitrate dehydrogenase 1 - IDH1 for a broad discussion on this topic) 5.
-<p><strong>Diffuse astrocytomas can be graded </strong>in according to a number of systems, the most popular being the <a href="/articles/who-grading-system-for-diffuse-astrocytomas">WHO grading system</a>. In general these grading systems focus on the presence or absence of a number of histological features <sup>3</sup>:</p><ul>- +<p><strong>Grading of diffuse astrocytic tumours in adults</strong> has been done according to a number of systems over the years, although by far the most popular now being the <a href="/articles/who-grading-system-for-diffuse-astrocytomas">WHO grading system</a>.</p><p>Historically these grading systems focused on the presence or absence of a number of histological features, although more recently genetic/molecular markers have been introduced into the grading schema <sup>3,6</sup>:</p><p>Histological features historically used include:</p><ul>
-<li>necrosis typically with perinecrotic palisading</li>-</ul><p>The most commonly used grading systems are: </p><ul>-<li><a href="/articles/who-grading-system-for-diffuse-astrocytomas">WHO grading system</a></li>- +<li>necrosis typically with perinecrotic palisading</li>
- +</ul><p>Classification systems include:</p><ul>
-<a href="/articles/st-anne-mayo-astrocytoma-grading-system">St.Anne-Mayo grading system</a> </li>-<li><a href="/articles/diffuse-astrocytomas-classification-kernohan">Kernohan grading system</a></li>- +<a href="/articles/who-grading-system-for-diffuse-astrocytomas">WHO grading system</a> (most common)</li>
- +<li>
- +<a href="/articles/st-anne-mayo-grading-system-of-astrocytomas">St.Anne-Mayo grading system</a> </li>
- +<li><a href="/articles/kernohan-grading-system-for-diffuse-astroctyomas">Kernohan grading system</a></li>
-</ul><p>Direct equivalence between the grades of various grading systems is of course not possible (otherwise they wouldn't be different systems), and thus care should be taken to state which system is being used <sup>4</sup>. </p><p>It is well recognised that pathological classification has a high interobserver variation and thus imperfectly predicts clinical outcomes <sup>5</sup>. </p><p>Recent studies have shown that the genetic status of these tumours are more reflective of their subtypes than the histologic grading (please refer on <a title="Isocitrate dehydrogenase 1 (IDH1)" href="/articles/isocitrate-dehydrogenase-1-idh1">isocitrate dehydrogenase 1 - IDH1</a> for a broad discussion on this topic) <sup>5</sup>. </p>- +</ul><p>Direct equivalence between the grades of various grading systems is of course not possible (otherwise they wouldn't be different systems), and thus care should be taken to state which system is being used and, in some situations, which edition; for example, the 5th edition (2021) WHO classification of CNS tumours suggests prefacing the grade by "WHO CNS" <sup>4,6</sup>. </p><p>It should be noted that it is well recognised that pathological classification has a high interobserver variation and thus imperfectly predicts clinical outcomes <sup>5</sup>. </p>
References changed:
- 6. Louis D, Perry A, Wesseling P et al. The 2021 WHO Classification of Tumors of the Central Nervous System: A Summary. Neuro Oncol. 2021;23(8):1231-51. <a href="https://doi.org/10.1093/neuonc/noab106">doi:10.1093/neuonc/noab106</a>