CNS5:Pleomorphic xanthoastrocytoma: Difference between revisions

<span style="color:#0070C0">(''General Instructions – The focus of these pages is the clinically significant genetic alterations in each disease type. This is based on up-to-date knowledge from multiple resources such as PubMed and the WHO classification books. The CCGA is meant to be a supplemental resource to the WHO classification books; the CCGA captures in a continually updated wiki-stye manner the current genetics/genomics knowledge of each disease, which evolves more rapidly than books can be revised and published. If the same disease is described in multiple WHO classification books, the genetics-related information for that disease will be consolidated into a single main page that has this template (other pages would only contain a link to this main page). Use [https://www.genenames.org/ <u>HUGO-approved gene names and symbols</u>] (italicized when appropriate), [https://varnomen.hgvs.org/ <u>HGVS-based nomenclature for variants</u>], as well as generic names of drugs and testing platforms or assays if applicable. Please complete tables whenever possible and do not delete them (add N/A if not applicable in the table and delete the examples); to add (or move) a row or column in a table, click nearby within the table and select the > symbol that appears. Please do not delete or alter the section headings. The use of bullet points alongside short blocks of text rather than only large paragraphs is encouraged. Additional instructions below in italicized blue text should not be included in the final page content. Please also see'' </span><u>''[[Author_Instructions]]''</u><span style="color:#0070C0"> ''and [[Frequently Asked Questions (FAQs)|<u>FAQs</u>]] as well as contact your [[Leadership|<u>Associate Editor</u>]] or [mailto:CCGA@cancergenomics.org <u>Technical Support</u>].)''</span>

==Related Terminology==

==Gene Rearrangements==

|''BRAF''||''BRAF''-''KIAA1549'' (rare), ''RAF1'' fusions, ''NTRK2''/''ALK''/''NTRK1'' (very rare in PXA)||Aberrant MAPK pathway activation (i.e BRAF p.V600E variant)||N/A

|BRAF p.V600E is diagnostic and predictive; kinase fusions targetable in rare cases<ref name=":0">{{Cite journal|last=Phillips|first=Joanna J.|last2=Gong|first2=Henry|last3=Chen|first3=Katharine|last4=Joseph|first4=Nancy M.|last5=van Ziffle|first5=Jessica|last6=Bastian|first6=Boris C.|last7=Grenert|first7=James P.|last8=Kline|first8=Cassie N.|last9=Mueller|first9=Sabine|date=2019-01|title=The genetic landscape of anaplastic pleomorphic xanthoastrocytoma|url=https://pubmed.ncbi.nlm.nih.gov/30051528|journal=Brain Pathology (Zurich, Switzerland)|volume=29|issue=1|pages=85–96|doi=10.1111/bpa.12639|issn=1750-3639|pmc=7837273|pmid=30051528}}</ref><ref>{{Cite journal|last=Vaubel|first=Rachael A.|last2=Caron|first2=Alissa A.|last3=Yamada|first3=Seiji|last4=Decker|first4=Paul A.|last5=Eckel Passow|first5=Jeanette E.|last6=Rodriguez|first6=Fausto J.|last7=Nageswara Rao|first7=Amulya A.|last8=Lachance|first8=Daniel|last9=Parney|first9=Ian|date=2018-03|title=Recurrent copy number alterations in low-grade and anaplastic pleomorphic xanthoastrocytoma with and without BRAF V600E mutation|url=https://pmc.ncbi.nlm.nih.gov/articles/PMC5807227/|journal=Brain Pathology (Zurich, Switzerland)|volume=28|issue=2|pages=172–182|doi=10.1111/bpa.12495|issn=1750-3639|pmc=5807227|pmid=28181325}}</ref> <ref>{{Cite journal|last=Tian|first=Lei|last2=Sun|first2=Wei|last3=Lou|first3=Lei|last4=Wang|first4=Wenyan|last5=Li|first5=Yanan|last6=Zhou|first6=Huandi|last7=Xiao|first7=Zhiqing|last8=Xue|first8=Xiaoying|date=2025|title=Pleomorphic xanthoastrocytoma with multiple recurrences and continuous malignant progression to bone metastasis: a case report|url=https://pmc.ncbi.nlm.nih.gov/articles/PMC12174448/|journal=Frontiers in Surgery|volume=12|pages=1595199|doi=10.3389/fsurg.2025.1595199|issn=2296-875X|pmc=12174448|pmid=40535548}}</ref><ref>{{Cite journal|last=Di Nunno|first=Vincenzo|last2=Gatto|first2=Lidia|last3=Tosoni|first3=Alicia|last4=Bartolini|first4=Stefania|last5=Franceschi|first5=Enrico|date=2022|title=Implications of BRAF V600E mutation in gliomas: Molecular considerations, prognostic value and treatment evolution|url=https://pmc.ncbi.nlm.nih.gov/articles/PMC9846085/|journal=Frontiers in Oncology|volume=12|pages=1067252|doi=10.3389/fonc.2022.1067252|issn=2234-943X|pmc=9846085|pmid=36686797}}</ref>

|Co-occurrence with BRAF p.V600E supports PXA diagnosis

|TERT

|NTRK2, ALK, RAF1

|Fusions: NACC2-NTRK2, BEND5-NTRK2, PPP1CB-ALK, etc.

|Context-dependent ( e.g. For patients with CNS tumors who harbor NTRK fusions, TRK inhibitors such as larotrectinib or repotrectinib are considered a preferred therapy, regardless of histology, if other options are limited) NCCN CNS Cancer guidelines

|Reported in individual cases; more common in glioneuronal/low-grade gliomas

|CDKN2A, CDKN2B

|EGFR not typically amplified)

|No (however, frequently mentioned in literature as a recurrent copy number change in PXA<ref>{{Cite journal|last=Vaubel|first=Rachael|last2=Zschernack|first2=Valentina|last3=Tran|first3=Quynh T.|last4=Jenkins|first4=Sarah|last5=Caron|first5=Alissa|last6=Milosevic|first6=Dragana|last7=Smadbeck|first7=James|last8=Vasmatzis|first8=George|last9=Kandels|first9=Daniela|date=2021-01|title=Biology and grading of pleomorphic xanthoastrocytoma-what have we learned about it?|url=https://pmc.ncbi.nlm.nih.gov/articles/PMC8018001/|journal=Brain Pathology (Zurich, Switzerland)|volume=31|issue=1|pages=20–32|doi=10.1111/bpa.12874|issn=1750-3639|pmc=8018001|pmid=32619305}}</ref>

|NF2, others

|CDKN2A, CDKN2B

|Pleomorphic xanthoastrocytoma (PXA) not identified as a high‑TMB or focal amplifications. No MSI‑driven marker in PXA. Global mutation pattern in PXA dominated by MAPK activation (BRAF or kinase fusions) plus CDKN2A/B loss

|CDKN2A/B loss defining feature of PXA; not associated with grade or BRAF status; central to PXA biology

Put your text here and fill in the table <span style="color:#0070C0">(''Instructions: This table is not meant to be an exhaustive list; please include only genes/alterations that are recurrent or common as well either disease defining and/or clinically significant. If a gene has multiple mechanisms depending on the type or site of the alteration, add multiple entries in the table. For clinical significance, denote associations with FDA-approved therapy (not an extensive list of applicable drugs) and NCCN or other national guidelines if applicable; Can also refer to CGC workgroup tables as linked on the homepage if applicable as well as any high impact papers or reviews of gene mutations in this entity. Details on clinical significance such as prognosis and other important information such as concomitant and mutually exclusive mutations can be provided in the notes section. Please include references throughout the table. Do not delete the table.'') </span>

|BRAF

|TERT

|IDH1/IDH2

|NTRK2, ALK

Dominant epigenomic themes in Pleomorphic xanthoastrocytoma (PXA) are: a distinct methylation class tied to MAPK activation and CDKN2A/B loss, progressive promoter hypermethylation in anaplastic transformation, frequent MGMT promoter methylation, and a relative absence of the H3/ATRX-driven epigenetic programs seen in other glioma subtypes<ref>{{Cite journal|last=Martínez|first=Ramón|last2=Carmona|first2=F. Javier|last3=Vizoso|first3=Miguel|last4=Rohde|first4=Veit|last5=Kirsch|first5=Matthias|last6=Schackert|first6=Gabriele|last7=Ropero|first7=Santiago|last8=Paulus|first8=Werner|last9=Barrantes|first9=Alonso|date=2014-03-20|title=DNA methylation alterations in grade II- and anaplastic pleomorphic xanthoastrocytoma|url=https://pubmed.ncbi.nlm.nih.gov/24650279|journal=BMC cancer|volume=14|pages=213|doi=10.1186/1471-2407-14-213|issn=1471-2407|pmc=4000050|pmid=24650279}}</ref><ref>{{Cite journal|last=Tang|first=Karen|last2=Kurland|first2=David|last3=Vasudevaraja|first3=Varshini|last4=Serrano|first4=Jonathan|last5=Delorenzo|first5=Michael|last6=Radmanesh|first6=Alireza|last7=Thomas|first7=Cheddhi|last8=Spino|first8=Marissa|last9=Gardner|first9=Sharon|date=2020-08-01|title=Exploring DNA Methylation for Prognosis and Analyzing the Tumor Microenvironment in Pleomorphic Xanthoastrocytoma|url=https://pmc.ncbi.nlm.nih.gov/articles/PMC8453609/|journal=Journal of Neuropathology and Experimental Neurology|volume=79|issue=8|pages=880–890|doi=10.1093/jnen/nlaa051|issn=1554-6578|pmc=8453609|pmid=32594172}}</ref>.

|TERT promoter mutations or amplification

(use the "Cite" icon at the top of the page) <span style="color:#0070C0">(''Instructions: Add each reference into the text above by clicking where you want to insert the reference, selecting the “Cite” icon at the top of the wiki page, and using the “Automatic” tab option to search by PMID to select the reference to insert. If a PMID is not available, such as for a book, please use the “Cite” icon, select “Manual” and then “Basic Form”, and include the entire reference. To insert the same reference again later in the page, select the “Cite” icon and “Re-use” to find the reference; DO NOT insert the same reference twice using the “Automatic” tab as it will be treated as two separate references. The reference list in this section will be automatically generated and sorted''</span><span style="color:#0070C0">''.''</span><span style="color:#0070C0">)</span>

 

<nowiki>*</nowiki>''Citation of this Page'': “Pleomorphic xanthoastrocytoma”. Compendium of Cancer Genome Aberrations (CCGA), Cancer Genomics Consortium (CGC), updated {{REVISIONMONTH}}/{{REVISIONDAY}}/{{REVISIONYEAR}}, <nowiki>https://ccga.io/index.php/CNS5:Pleomorphic xanthoastrocytoma</nowiki>.