{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T19:01:21Z","timestamp":1790190081694,"version":"4.1.0"},"reference-count":37,"publisher":"Oxford University Press (OUP)","license":[{"start":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T00:00:00Z","timestamp":1790121600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/pages\/standard-publication-reuse-rights"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>The presence of a CDKN2A homozygous deletion (HD) plays an important role in the diagnostic approach of neuropathologists to several central nervous system (CNS) tumors. CDKN2A is located on chromosome 9p21, next to CDKN2B and MTAP, and encodes for the protein p16. CDKN2A\/B HD constitutes a frequent alteration in some circumscribed gliomas such as high-grade astrocytomas with piloid features (HGAP) and pleomorphic xanthoastrocytomas (PXA). The diagnosis of these tumor types remains complex and having a rapid and easy tool to suggest these diagnoses would be useful. Herein, we studied a cohort of 42 HGAP and PXA to analyze the concordance of CDKN2A\/B and MTAP status between 3 different molecular techniques (FISH, DNA-methylation profiling providing copy number variation analysis, and SNP array), and compared the results to those of p16 and MTAP immunohistochemistry. HD was present in 11\/12 HGAP and 28\/30 PXA, however, with a wide variety of deletion size, including of CDKN2A, CDKN2B, and MTAP genes. There was excellent concordance between p16\/MTAP immunoexpression and the genetic detection of HD, demonstrating 100% sensitivity and 100% specificity. In conclusion, combined p16\/MTAP IHC presented a positive predictive value for detecting HD and may assist neuropathologists in their diagnostic approach to circumscribed glial\/glioneuronal tumors.<\/jats:p>","DOI":"10.1093\/jnen\/nlag086","type":"journal-article","created":{"date-parts":[[2026,8,24]],"date-time":"2026-08-24T11:25:48Z","timestamp":1787570748000},"source":"Crossref","is-referenced-by-count":0,"title":["<i>CDKN2A\/B<\/i>\n                    status can be assessed by p16\/MTAP immunohistochemistry as a practical surrogate in pleomorphic xanthoastrocytoma and high-grade astrocytoma with piloid features"],"prefix":"10.1093","author":[{"given":"Giorgia Antonia","family":"Simboli","sequence":"first","affiliation":[{"name":"Department of Neuropathology, GHU Paris-Psychiatrie et Neurosciences, Sainte-Anne Hospital , Paris,","place":["France"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Audrey","family":"Rousseau","sequence":"additional","affiliation":[{"name":"Department of Pathology, Angers University Hospital , Angers,","place":["France"]},{"name":"Universit\u00e9 d\u2019Angers, Inserm UMR 1307, CNRS UMR 6075, Nantes Universit\u00e9, CRCI2NA , Angers,","place":["France"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Laetitia","family":"Basset","sequence":"additional","affiliation":[{"name":"Department of Pathology, Angers University Hospital , Angers,","place":["France"]},{"name":"Universit\u00e9 d\u2019Angers, Inserm UMR 1307, CNRS UMR 6075, Nantes Universit\u00e9, CRCI2NA , Angers,","place":["France"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rapha\u00ebl","family":"Saffroy","sequence":"additional","affiliation":[{"name":"Department of Biochemistry and Oncogenetics, Paul Brousse Hospital , Villejuif,","place":["France"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lauren","family":"Hasty","sequence":"additional","affiliation":[{"name":"Department of Neuropathology, GHU Paris-Psychiatrie et Neurosciences, Sainte-Anne Hospital , Paris,","place":["France"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Farah","family":"Sassi","sequence":"additional","affiliation":[{"name":"Department of Neuropathology, GHU Paris-Psychiatrie et Neurosciences, Sainte-Anne Hospital , Paris,","place":["France"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alice","family":"M\u00e9tais","sequence":"additional","affiliation":[{"name":"Department of Neuropathology, GHU Paris-Psychiatrie et Neurosciences, Sainte-Anne Hospital , Paris,","place":["France"]},{"name":"Universit\u00e9 Paris Cit\u00e9, Institute of Psychiatry and Neuroscience of Paris (IPNP), INSERM U1266, Imabrain Team , Paris,","place":["France"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pascale","family":"Varlet","sequence":"additional","affiliation":[{"name":"Department of Neuropathology, GHU Paris-Psychiatrie et Neurosciences, Sainte-Anne Hospital , Paris,","place":["France"]},{"name":"Universit\u00e9 Paris Cit\u00e9, Institute of Psychiatry and Neuroscience of Paris (IPNP), INSERM U1266, Imabrain Team , Paris,","place":["France"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Arnault","family":"Tauzi\u00e8de-Espariat","sequence":"additional","affiliation":[{"name":"Department of Neuropathology, GHU Paris-Psychiatrie et Neurosciences, Sainte-Anne Hospital , Paris,","place":["France"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2026,9,23]]},"reference":[{"key":"2026092314204101300_nlag086-B1","doi-asserted-by":"crossref","first-page":"2254","DOI":"10.3390\/biomedicines11082254","article-title":"Cyclin 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variations in pleomorphic xanthoastrocytoma: implications for diagnostic approach","volume":"4","author":"Reuss","year":"2023","journal-title":"Free Neuropathol."},{"key":"2026092314204101300_nlag086-B8","doi-asserted-by":"crossref","first-page":"71","DOI":"10.1007\/s00401-022-02513-5","article-title":"Expanded analysis of high-grade astrocytoma with piloid features identifies an epigenetically and clinically distinct subtype associated with neurofibromatosis type 1","volume":"145","author":"Cimino","year":"2023","journal-title":"Acta Neuropathol (Berl)."},{"key":"2026092314204101300_nlag086-B9","doi-asserted-by":"crossref","first-page":"2","DOI":"10.1007\/s00401-018-1837-8","article-title":"Anaplastic astrocytoma with piloid features, a novel molecular class of IDH wildtype glioma with recurrent MAPK pathway, CDKN2A\/B and ATRX alterations","volume":"136","author":"Reinhardt","year":"2018","journal-title":"Acta Neuropathol 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