Changes

!Finding!!Marker

!Finding!!Marker

|-

|-

|Positive ||CD34

|Positive||CD34

|-

|-

|Positive ||STAT6 (nuclear)

|Positive||STAT6 (nuclear)

|-

|-

|Positive||BCL2 (30%)

|Positive||BCL2 (30%)

|EMA (30%)

|EMA (30%)

|-

|-

|Positive  

|Positive

|Actin (20%)

|Actin (20%)

|-

|-

|TERT

|TERT

|Oncogene

|Oncogene

|13-28% <ref>{{Cite journal|last=Bahrami|first=Armita|last2=Lee|first2=Seungjae|last3=Schaefer|first3=Inga-Marie|last4=Boland|first4=Jennifer M|last5=Patton|first5=Kurt T|last6=Pounds|first6=Stanley|last7=Fletcher|first7=Christopher D|date=2016-12|title=TERT promoter mutations and prognosis in solitary fibrous tumor|url=https://linkinghub.elsevier.com/retrieve/pii/S0893395222023328|journal=Modern Pathology|language=en|volume=29|issue=12|pages=1511–1522|doi=10.1038/modpathol.2016.126}}</ref><ref>{{Cite journal|last=Liu|first=Xiaoli|last2=Bishop|first2=Justin|last3=Shan|first3=Yuan|last4=Pai|first4=Sara|last5=Liu|first5=Dingxie|last6=Murugan|first6=Avaniyapuram Kannan|last7=Sun|first7=Hui|last8=El-Naggar|first8=Adel K|last9=Xing|first9=Mingzhao|date=2013-08|title=Highly prevalent TERT promoter mutations in aggressive thyroid cancers|url=https://erc.bioscientifica.com/view/journals/erc/20/4/603.xml|journal=Endocrine-Related Cancer|volume=20|issue=4|pages=603–610|doi=10.1530/ERC-13-0210|issn=1351-0088|pmc=PMC3782569|pmid=23766237}}</ref><ref>{{Cite journal|last=Killela|first=Patrick J.|last2=Reitman|first2=Zachary J.|last3=Jiao|first3=Yuchen|last4=Bettegowda|first4=Chetan|last5=Agrawal|first5=Nishant|last6=Diaz|first6=Luis A.|last7=Friedman|first7=Allan H.|last8=Friedman|first8=Henry|last9=Gallia|first9=Gary L.|date=2013-04-09|title=TERT promoter mutations occur frequently in gliomas and a subset of tumors derived from cells with low rates of self-renewal|url=https://pnas.org/doi/full/10.1073/pnas.1303607110|journal=Proceedings of the National Academy of Sciences|language=en|volume=110|issue=15|pages=6021–6026|doi=10.1073/pnas.1303607110|issn=0027-8424|pmc=PMC3625331|pmid=23530248}}</ref><ref>{{Cite journal|last=Koelsche|first=Christian|last2=Renner|first2=Marcus|last3=Hartmann|first3=Wolfgang|last4=Brandt|first4=Regine|last5=Lehner|first5=Burkhard|last6=Waldburger|first6=Nina|last7=Alldinger|first7=Ingo|last8=Schmitt|first8=Thomas|last9=Egerer|first9=Gerlinde|date=2014-12|title=TERT promoter hotspot mutations are recurrent in myxoid liposarcomas but rare in other soft tissue sarcoma entities|url=https://jeccr.biomedcentral.com/articles/10.1186/1756-9966-33-33|journal=Journal of Experimental & Clinical Cancer Research|language=en|volume=33|issue=1|doi=10.1186/1756-9966-33-33|issn=1756-9966}}</ref>

|13-29% <ref name=":3">{{Cite journal|last=Bahrami|first=Armita|last2=Lee|first2=Seungjae|last3=Schaefer|first3=Inga-Marie|last4=Boland|first4=Jennifer M|last5=Patton|first5=Kurt T|last6=Pounds|first6=Stanley|last7=Fletcher|first7=Christopher D|date=2016-12|title=TERT promoter mutations and prognosis in solitary fibrous tumor|url=https://linkinghub.elsevier.com/retrieve/pii/S0893395222023328|journal=Modern Pathology|language=en|volume=29|issue=12|pages=1511–1522|doi=10.1038/modpathol.2016.126}}</ref><ref>{{Cite journal|last=Liu|first=Xiaoli|last2=Bishop|first2=Justin|last3=Shan|first3=Yuan|last4=Pai|first4=Sara|last5=Liu|first5=Dingxie|last6=Murugan|first6=Avaniyapuram Kannan|last7=Sun|first7=Hui|last8=El-Naggar|first8=Adel K|last9=Xing|first9=Mingzhao|date=2013-08|title=Highly prevalent TERT promoter mutations in aggressive thyroid cancers|url=https://erc.bioscientifica.com/view/journals/erc/20/4/603.xml|journal=Endocrine-Related Cancer|volume=20|issue=4|pages=603–610|doi=10.1530/ERC-13-0210|issn=1351-0088|pmc=PMC3782569|pmid=23766237}}</ref><ref>{{Cite journal|last=Killela|first=Patrick J.|last2=Reitman|first2=Zachary J.|last3=Jiao|first3=Yuchen|last4=Bettegowda|first4=Chetan|last5=Agrawal|first5=Nishant|last6=Diaz|first6=Luis A.|last7=Friedman|first7=Allan H.|last8=Friedman|first8=Henry|last9=Gallia|first9=Gary L.|date=2013-04-09|title=TERT promoter mutations occur frequently in gliomas and a subset of tumors derived from cells with low rates of self-renewal|url=https://pnas.org/doi/full/10.1073/pnas.1303607110|journal=Proceedings of the National Academy of Sciences|language=en|volume=110|issue=15|pages=6021–6026|doi=10.1073/pnas.1303607110|issn=0027-8424|pmc=PMC3625331|pmid=23530248}}</ref><ref>{{Cite journal|last=Koelsche|first=Christian|last2=Renner|first2=Marcus|last3=Hartmann|first3=Wolfgang|last4=Brandt|first4=Regine|last5=Lehner|first5=Burkhard|last6=Waldburger|first6=Nina|last7=Alldinger|first7=Ingo|last8=Schmitt|first8=Thomas|last9=Egerer|first9=Gerlinde|date=2014-12|title=TERT promoter hotspot mutations are recurrent in myxoid liposarcomas but rare in other soft tissue sarcoma entities|url=https://jeccr.biomedcentral.com/articles/10.1186/1756-9966-33-33|journal=Journal of Experimental & Clinical Cancer Research|language=en|volume=33|issue=1|doi=10.1186/1756-9966-33-33|issn=1756-9966}}</ref><ref name=":2">{{Cite journal|last=Demicco|first=Elizabeth G.|last2=Wani|first2=Khalida|last3=Ingram|first3=Davis|last4=Wagner|first4=Michael|last5=Maki|first5=Robert G.|last6=Rizzo|first6=Anthony|last7=Meeker|first7=Alan|last8=Lazar|first8=Alexander J.|last9=Wang|first9=Wei-Lien|date=2018-11|title=TERT promoter mutations in solitary fibrous tumour|url=https://pubmed.ncbi.nlm.nih.gov/29985536|journal=Histopathology|volume=73|issue=5|pages=843–851|doi=10.1111/his.13703|issn=1365-2559|pmid=29985536}}</ref>

|

|

|

|

|No

|No

|Yes<ref name=":0" /><ref>{{Cite journal|last=Park|first=Hyung Kyu|last2=Yu|first2=Dan Bi|last3=Sung|first3=Minjung|last4=Oh|first4=Ensel|last5=Kim|first5=Mingi|last6=Song|first6=Ji-Young|last7=Lee|first7=Mi-Sook|last8=Jung|first8=Kyungsoo|last9=Noh|first9=Ka-Won|date=2019-10|title=Molecular changes in solitary fibrous tumor progression|url=https://pubmed.ncbi.nlm.nih.gov/31321477|journal=Journal of Molecular Medicine (Berlin, Germany)|volume=97|issue=10|pages=1413–1425|doi=10.1007/s00109-019-01815-8|issn=1432-1440|pmc=6746689|pmid=31321477}}</ref><ref>{{Cite journal|last=Demicco|first=Elizabeth G.|last2=Wani|first2=Khalida|last3=Ingram|first3=Davis|last4=Wagner|first4=Michael|last5=Maki|first5=Robert G.|last6=Rizzo|first6=Anthony|last7=Meeker|first7=Alan|last8=Lazar|first8=Alexander J.|last9=Wang|first9=Wei-Lien|date=2018-11|title=TERT promoter mutations in solitary fibrous tumour|url=https://pubmed.ncbi.nlm.nih.gov/29985536|journal=Histopathology|volume=73|issue=5|pages=843–851|doi=10.1111/his.13703|issn=1365-2559|pmid=29985536}}</ref><ref>{{Cite journal|last=Bahrami|first=Armita|last2=Lee|first2=Seungjae|last3=Schaefer|first3=Inga-Marie|last4=Boland|first4=Jennifer M.|last5=Patton|first5=Kurt T.|last6=Pounds|first6=Stanley|last7=Fletcher|first7=Christopher D.|date=2016-12|title=TERT promoter mutations and prognosis in solitary fibrous tumor|url=https://pubmed.ncbi.nlm.nih.gov/27562490|journal=Modern Pathology: An Official Journal of the United States and Canadian Academy of Pathology, Inc|volume=29|issue=12|pages=1511–1522|doi=10.1038/modpathol.2016.126|issn=1530-0285|pmc=5731237|pmid=27562490}}</ref>

|Yes<ref name=":0" /><ref name=":3" /><ref name=":2" /><ref>{{Cite journal|last=Park|first=Hyung Kyu|last2=Yu|first2=Dan Bi|last3=Sung|first3=Minjung|last4=Oh|first4=Ensel|last5=Kim|first5=Mingi|last6=Song|first6=Ji-Young|last7=Lee|first7=Mi-Sook|last8=Jung|first8=Kyungsoo|last9=Noh|first9=Ka-Won|date=2019-10|title=Molecular changes in solitary fibrous tumor progression|url=https://pubmed.ncbi.nlm.nih.gov/31321477|journal=Journal of Molecular Medicine (Berlin, Germany)|volume=97|issue=10|pages=1413–1425|doi=10.1007/s00109-019-01815-8|issn=1432-1440|pmc=6746689|pmid=31321477}}</ref><ref>{{Cite journal|last=Bahrami|first=Armita|last2=Lee|first2=Seungjae|last3=Schaefer|first3=Inga-Marie|last4=Boland|first4=Jennifer M.|last5=Patton|first5=Kurt T.|last6=Pounds|first6=Stanley|last7=Fletcher|first7=Christopher D.|date=2016-12|title=TERT promoter mutations and prognosis in solitary fibrous tumor|url=https://pubmed.ncbi.nlm.nih.gov/27562490|journal=Modern Pathology: An Official Journal of the United States and Canadian Academy of Pathology, Inc|volume=29|issue=12|pages=1511–1522|doi=10.1038/modpathol.2016.126|issn=1530-0285|pmc=5731237|pmid=27562490}}</ref>

|No

|No

|

|

|TP53

|TP53

|TSG

|TSG

|

|

|

|

|

|No

|

|Yes<ref>{{Cite journal|last=Machado|first=Isidro|last2=Morales|first2=Gema Nieto|last3=Cruz|first3=Julia|last4=Lavernia|first4=Javier|last5=Giner|first5=Francisco|last6=Navarro|first6=Samuel|last7=Ferrandez|first7=Antonio|last8=Llombart-Bosch|first8=Antonio|date=2020-04|title=Solitary fibrous tumor: a case series identifying pathological adverse factors-implications for risk stratification and classification|url=https://pubmed.ncbi.nlm.nih.gov/31529158|journal=Virchows Archiv: An International Journal of Pathology|volume=476|issue=4|pages=597–607|doi=10.1007/s00428-019-02660-3|issn=1432-2307|pmid=31529158}}</ref><ref name=":4" />

|

|No

|

|Single base pair substitution have been identified in exon 5 or exon 6 of TP53. <ref name=":3" /> Mutations of TP53 have been associated with malignant and dedifferentiated SFTs.<ref>{{Cite journal|last=Dagrada|first=Gian P.|last2=Spagnuolo|first2=Rosalin D.|last3=Mauro|first3=Valentina|last4=Tamborini|first4=Elena|last5=Cesana|first5=Luca|last6=Gronchi|first6=Alessandro|last7=Stacchiotti|first7=Silvia|last8=Pierotti|first8=Marco A.|last9=Negri|first9=Tiziana|date=2015-08|title=Solitary fibrous tumors: loss of chimeric protein expression and genomic instability mark dedifferentiation|url=https://pubmed.ncbi.nlm.nih.gov/26022454|journal=Modern Pathology: An Official Journal of the United States and Canadian Academy of Pathology, Inc|volume=28|issue=8|pages=1074–1083|doi=10.1038/modpathol.2015.70|issn=1530-0285|pmid=26022454}}</ref><ref>{{Cite journal|last=Kurisaki-Arakawa|first=Aiko|last2=Akaike|first2=Keisuke|last3=Hara|first3=Kieko|last4=Arakawa|first4=Atsushi|last5=Takahashi|first5=Michiko|last6=Mitani|first6=Keiko|last7=Yao|first7=Takashi|last8=Saito|first8=Tsuyoshi|date=2014-11|title=A case of dedifferentiated solitary fibrous tumor in the pelvis with TP53 mutation|url=https://pubmed.ncbi.nlm.nih.gov/25015562|journal=Virchows Archiv: An International Journal of Pathology|volume=465|issue=5|pages=615–621|doi=10.1007/s00428-014-1625-3|issn=1432-2307|pmid=25015562}}</ref><ref>{{Cite journal|last=Nonaka|first=Haruna|last2=Kandori|first2=Shuya|last3=Nitta|first3=Satoshi|last4=Shiga|first4=Masanobu|last5=Nagumo|first5=Yoshiyuki|last6=Kimura|first6=Tomokazu|last7=Kawahara|first7=Takashi|last8=Negoro|first8=Hiromitsu|last9=Hoshi|first9=Akio|date=2021|title=Case Report: Molecular Characterization of Aggressive Malignant Retroperitoneal Solitary Fibrous Tumor: A Case Study|url=https://pubmed.ncbi.nlm.nih.gov/35004271|journal=Frontiers in Oncology|volume=11|pages=736969|doi=10.3389/fonc.2021.736969|issn=2234-943X|pmc=8727594|pmid=35004271}}</ref>

|

|-

|-

|APAF1

|APAF1

|Other

|Other

|

|66.7%

|

|

|

|

|Yes<ref name=":1" />

|Yes<ref name=":1" />

|No

|No

|Alteration of APAF1 results in gain of a stop codon. The gene is inactivated by DNA methylation of the promoter region. Decreased APAF1 is considered to lead to inhibition of apoptosis.  This alteration and decreased APAF1 mRNA expression was observed in metastatic SFT.  

|Alteration of APAF1 results in gain of a stop codon. The gene is inactivated by DNA methylation of the promoter region. Decreased APAF1 is considered to lead to inhibition of apoptosis.  This alteration and decreased APAF1 mRNA expression was observed in metastatic SFT.

|}

|}

==Epigenomic Alterations==

==Epigenomic Alterations==

|}

|}

==Genetic Diagnostic Testing Methods==

==Genetic Diagnostic Testing Methods==

Ancillary studies such as immunohistochemistry and molecular tests are useful in differentiating soft tissue tumors. SFTs have historically been diagnosed by morphology and strong diffuse CD34 positivity. Additional immunohistochemical phenotype previously used for identification included expression of Bcl2, CD99, and vimentin and absence of expression of epithelial, muscle, and neural markers. However, the introduction of STAT6 (signal transducer and activator of transcription 6) immunostain now dominates due to its high sensitivity and specificity. STAT6 expression is demonstrated by nuclear staining. Molecular testing by next generation sequencing is also highly useful in detecting the NAB2::STAT6 fusion. Breakapart fluorescence in situ hybridization (FISH) probe for STAT6 can detect rearrangement of this gene.  In the context of SFT, the rearrangement of the ''STAT6'' gene is highly suggestive for the presence of ''NAB2-STAT6'' fusion. [https://pubmed.ncbi.nlm.nih.gov/27802414/ A dual color dual fusion probe targeting both genes would be a direct confirmation for ''NAB2-STAT6'' fusion.]

Ancillary studies such as immunohistochemistry and molecular tests are useful in differentiating soft tissue tumors. SFTs have historically been diagnosed by morphology and strong diffuse CD34 positivity. Additional immunohistochemical phenotype previously used for identification included expression of Bcl2, CD99, and vimentin and absence of expression of epithelial, muscle, and neural markers. However, the introduction of STAT6 (signal transducer and activator of transcription 6) immunostain now dominates due to its high sensitivity and specificity. STAT6 expression is demonstrated by nuclear staining. Next generation sequencing (NGS) using mRNA is also highly useful in detecting the NAB2::STAT6 fusion. Breakapart fluorescence in situ hybridization (FISH) probe for STAT6 can detect rearrangement of this gene.  In the context of SFT, the rearrangement of the ''STAT6'' gene is highly suggestive for the presence of ''NAB2-STAT6'' fusion. [https://pubmed.ncbi.nlm.nih.gov/27802414/ A dual color dual fusion probe targeting both genes would be a direct confirmation for ''NAB2-STAT6'' fusion.]

==Familial Forms==

==Familial Forms==

Not Applicable

Not Applicable