2
edits
Changes
→References
==Definition / Description of Disease==
==Definition / Description of Disease==
Aggressive subtype of peripheral T-cell lymphoma. HSTL is an extranodal T-cell lymphoma that is known to have a poor response to therapy and an overall poor prognosis. This lymphoma is characterized by sinusoidal infiltration of the liver, spleen and often bone marrow, and uncommonly lymph nodes by cytotoxic T-cells that most commonly express the γδ T-cell receptor. Less commonly, some patients may have a variant of this lymphoma that is associated with αβ expressing cytotoxic T-cells <ref name=":0">Medeiros LJ, O'Malley DP, Caraway NP, Vega F, Elenitoba-Johnson KS, Lim MS: AFIP Atlas of Tumor Pathology. Washington, DC: American Registry of Pathology, 2017.</ref><ref name=":1">{{Cite journal|title=BlueBooksOnline|url=https://tumourclassification.iarc.who.int/chaptercontent/63/229}}</ref><ref name=":2">Yabe M, Miranda RN, Medeiros LJ. Hepatosplenic T-cell Lymphoma: a review of clinicopathologic features, pathogenesis, and prognostic factors. ''Hum Pathol''. 2018;74:5‐16. doi:10.1016/j.humpath.2018.01.005</ref>. Most cases occur de novo, with a subset of approximately 20-30% occurring in the setting of iatrogenic immunosuppression <ref name=":2" />.
Aggressive subtype of peripheral T-cell lymphoma. HSTL is an extranodal T-cell lymphoma that is known to have a poor response to therapy and an overall poor prognosis. This lymphoma is characterized by sinusoidal infiltration of the liver, spleen and often bone marrow, and uncommonly lymph nodes by cytotoxic T-cells that most commonly express the γδ T-cell receptor. Less commonly, some patients may have a variant of this lymphoma that is associated with αβ expressing cytotoxic T-cells <ref name=":0">Medeiros LJ, O'Malley DP, Caraway NP, Vega F, Elenitoba-Johnson KS, Lim MS: AFIP Atlas of Tumor Pathology. Washington, DC: American Registry of Pathology, 2017.</ref><ref name=":1">{{Cite journal|title=Hepatosplenic T-cell lymphoma. In: WHO Classification of Tumours Editorial Board. Haematolymphoid tumours [Internet]|url=https://tumourclassification.iarc.who.int/chaptercontent/63/229|displayauthors=1|last=Medeiros|first=Jeffrey|date=2024|journal=WHO classification of tumours series, 5th ed.|volume=vol. 11|pages=|via=Lyon (France): International Agency for Research on Cancer}}</ref><ref name=":2">Yabe M, Miranda RN, Medeiros LJ. Hepatosplenic T-cell Lymphoma: a review of clinicopathologic features, pathogenesis, and prognostic factors. ''Hum Pathol''. 2018;74:5‐16. doi:10.1016/j.humpath.2018.01.005</ref>. Most cases occur de novo, with a subset of approximately 20-30% occurring in the setting of iatrogenic immunosuppression <ref name=":2" />.
==Synonyms / Terminology==
==Synonyms / Terminology==
==Epidemiology / Prevalence==
==Epidemiology / Prevalence==
* 1.4-2% of peripheral T-cell lymphomas<ref name=":1" />
*1.4-2% of peripheral T-cell lymphomas<ref name=":1" />
* ~75% are Classic γδ type<ref name=":1" />
*~75% are Classic γδ type<ref name=":1" />
* Male predominance in gamma-delta subtype<ref name=":1" />
*Male predominance in gamma-delta subtype<ref name=":1" />
* Median age ~ 35 years old<ref name=":2" />, 51% with age >60 years old<ref>{{Cite journal|last=Foss|first=Francine M.|last2=Horwitz|first2=Steven M.|last3=Civallero|first3=Monica|last4=Bellei|first4=Monica|last5=Marcheselli|first5=Luigi|last6=Kim|first6=Won Seog|last7=Cabrera|first7=Maria E.|last8=Dlouhy|first8=Ivan|last9=Nagler|first9=Arnon|date=2020-02|title=Incidence and outcomes of rare T cell lymphomas from the T Cell Project: hepatosplenic, enteropathy associated and peripheral gamma delta T cell lymphomas|url=https://pubmed.ncbi.nlm.nih.gov/31709579|journal=American Journal of Hematology|volume=95|issue=2|pages=151–155|doi=10.1002/ajh.25674|issn=1096-8652|pmc=8025136|pmid=31709579}}</ref>
*Median age ~ 35 years old<ref name=":2" />, 51% with age >60 years old<ref>{{Cite journal|last=Foss|first=Francine M.|last2=Horwitz|first2=Steven M.|last3=Civallero|first3=Monica|last4=Bellei|first4=Monica|last5=Marcheselli|first5=Luigi|last6=Kim|first6=Won Seog|last7=Cabrera|first7=Maria E.|last8=Dlouhy|first8=Ivan|last9=Nagler|first9=Arnon|date=2020-02|title=Incidence and outcomes of rare T cell lymphomas from the T Cell Project: hepatosplenic, enteropathy associated and peripheral gamma delta T cell lymphomas|url=https://pubmed.ncbi.nlm.nih.gov/31709579|journal=American Journal of Hematology|volume=95|issue=2|pages=151–155|doi=10.1002/ajh.25674|issn=1096-8652|pmc=8025136|pmid=31709579}}</ref>
==Clinical Features==
==Clinical Features==
==Chromosomal Rearrangements (Gene Fusions)==
==Chromosomal Rearrangements (Gene Fusions)==
* No known chromosomal rearrangements at this time
*No known chromosomal rearrangements at this time
==Individual Region Genomic Gain / Loss / LOH==
==Individual Region Genomic Gain / Loss / LOH==
==Characteristic Chromosomal Patterns==
==Characteristic Chromosomal Patterns==
* 7q aberrations and trisomy 8 are considered specific for HSTL, but not sensitive<ref name=":2" />
*7q aberrations and trisomy 8 are considered specific for HSTL, but not sensitive<ref name=":2" />
{| class="wikitable sortable"
{| class="wikitable sortable"
Cases with chromosome 7 abnormalities show:
Cases with chromosome 7 abnormalities show:
* Constant loss of 7p22.1p14.1 (34.88 Mb; 3506316-38406226 bp)<ref name=":3">{{Cite journal|last=Finalet Ferreiro|first=Julio|last2=Rouhigharabaei|first2=Leila|last3=Urbankova|first3=Helena|last4=van der Krogt|first4=Jo-Anne|last5=Michaux|first5=Lucienne|last6=Shetty|first6=Shashirekha|last7=Krenacs|first7=Laszlo|last8=Tousseyn|first8=Thomas|last9=De Paepe|first9=Pascale|date=2014|title=Integrative genomic and transcriptomic analysis identified candidate genes implicated in the pathogenesis of hepatosplenic T-cell lymphoma|url=https://pubmed.ncbi.nlm.nih.gov/25057852|journal=PloS One|volume=9|issue=7|pages=e102977|doi=10.1371/journal.pone.0102977|issn=1932-6203|pmc=4109958|pmid=25057852}}</ref>
*Constant loss of 7p22.1p14.1 (34.88 Mb; 3506316-38406226 bp)<ref name=":3">{{Cite journal|last=Finalet Ferreiro|first=Julio|last2=Rouhigharabaei|first2=Leila|last3=Urbankova|first3=Helena|last4=van der Krogt|first4=Jo-Anne|last5=Michaux|first5=Lucienne|last6=Shetty|first6=Shashirekha|last7=Krenacs|first7=Laszlo|last8=Tousseyn|first8=Thomas|last9=De Paepe|first9=Pascale|date=2014|title=Integrative genomic and transcriptomic analysis identified candidate genes implicated in the pathogenesis of hepatosplenic T-cell lymphoma|url=https://pubmed.ncbi.nlm.nih.gov/25057852|journal=PloS One|volume=9|issue=7|pages=e102977|doi=10.1371/journal.pone.0102977|issn=1932-6203|pmc=4109958|pmid=25057852}}</ref>
* Gain of 7q22.11q31.1 (38.77 Mb; 86259620–124892276 bp)<ref name=":3" /> Can be seen in conjunction with trisomy 8
*Gain of 7q22.11q31.1 (38.77 Mb; 86259620–124892276 bp)<ref name=":3" /> Can be seen in conjunction with trisomy 8
Can be seen in conjunction with trisomy 8
Can be seen in conjunction with trisomy 8
|No
|No
|
|
* See table under "Genomic Gain/Loss/LOH"
*See table under "Genomic Gain/Loss/LOH"
<br />
<br />
* Cases without diagnostic detection of i(7q) or trisomy 8, often have detection of these abnormalities at the time of relapse or disease progression<ref name=":2" />
*Cases without diagnostic detection of i(7q) or trisomy 8, often have detection of these abnormalities at the time of relapse or disease progression<ref name=":2" />
|-
|-
|Loss of chromosome 10q and gain of chromosome 1q
|Loss of chromosome 10q and gain of chromosome 1q
|No
|No
|
|
* occur in a significant minority of HSTL cases<ref name=":4" />
*occur in a significant minority of HSTL cases<ref name=":4" />
|}<br />
|}<br />
==Gene Mutations (SNV / INDEL)==
==Gene Mutations (SNV / INDEL)==
|Yes
|Yes
|
|
* Highest functional potency: ''STAT5B'' N642H and V712E mutations<ref name=":2" />
*Highest functional potency: ''STAT5B'' N642H and V712E mutations<ref name=":2" />
* One study showed increased CD56 expression with STAT5b<ref>{{Cite journal|last=Nicolae|first=A.|last2=Xi|first2=L.|last3=Pittaluga|first3=S.|last4=Abdullaev|first4=Z.|last5=Pack|first5=S. D.|last6=Chen|first6=J.|last7=Waldmann|first7=T. A.|last8=Jaffe|first8=E. S.|last9=Raffeld|first9=M.|date=2014-11|title=Frequent STAT5B mutations in γδ hepatosplenic T-cell lymphomas|url=https://pubmed.ncbi.nlm.nih.gov/24947020|journal=Leukemia|volume=28|issue=11|pages=2244–2248|doi=10.1038/leu.2014.200|issn=1476-5551|pmc=7701980|pmid=24947020}}</ref>
*One study showed increased CD56 expression with STAT5b<ref>{{Cite journal|last=Nicolae|first=A.|last2=Xi|first2=L.|last3=Pittaluga|first3=S.|last4=Abdullaev|first4=Z.|last5=Pack|first5=S. D.|last6=Chen|first6=J.|last7=Waldmann|first7=T. A.|last8=Jaffe|first8=E. S.|last9=Raffeld|first9=M.|date=2014-11|title=Frequent STAT5B mutations in γδ hepatosplenic T-cell lymphomas|url=https://pubmed.ncbi.nlm.nih.gov/24947020|journal=Leukemia|volume=28|issue=11|pages=2244–2248|doi=10.1038/leu.2014.200|issn=1476-5551|pmc=7701980|pmid=24947020}}</ref>
* Also seen in ~2% of T-large granular lymphocyte leukemia<ref name=":2" />
*Also seen in ~2% of T-large granular lymphocyte leukemia<ref name=":2" />
|-
|-
|PIK3CD
|PIK3CD
|Yes
|Yes
|
|
* Most frequently silenced gene and most frequent mutated chromatin modifier in HSTL<ref name=":4" />
*Most frequently silenced gene and most frequent mutated chromatin modifier in HSTL<ref name=":4" />
* More than 44% of patients had more than 1 mutation in SETD2<ref name=":2" />
*More than 44% of patients had more than 1 mutation in SETD2<ref name=":2" />
|-
|-
|INO80
|INO80
****Note: This finding is not specific to HSTL and can be seen in other T-cell lymphomas<ref name=":6" />
****Note: This finding is not specific to HSTL and can be seen in other T-cell lymphomas<ref name=":6" />
* A single study has shown use of IFNα2c therapy-induced changes in CpG methylation<ref name=":7">{{Cite journal|last=Bhat|first=Jaydeep|last2=Bergmann|first2=Anke K.|last3=Waschina|first3=Silvio|last4=Nerl|first4=Christoph|last5=Kaleta|first5=Christoph|last6=Siebert|first6=Reiner|last7=Ammerpohl|first7=Ole|last8=Kabelitz|first8=Dieter|date=2021-05|title=DNA methylation profile of a hepatosplenic gamma/delta T-cell lymphoma patient associated with response to interferon-α therapy|url=https://pubmed.ncbi.nlm.nih.gov/32820235|journal=Cellular & Molecular Immunology|volume=18|issue=5|pages=1332–1335|doi=10.1038/s41423-020-0518-4|issn=2042-0226|pmc=8093208|pmid=32820235}}</ref>
*A single study has shown use of IFNα2c therapy-induced changes in CpG methylation<ref name=":7">{{Cite journal|last=Bhat|first=Jaydeep|last2=Bergmann|first2=Anke K.|last3=Waschina|first3=Silvio|last4=Nerl|first4=Christoph|last5=Kaleta|first5=Christoph|last6=Siebert|first6=Reiner|last7=Ammerpohl|first7=Ole|last8=Kabelitz|first8=Dieter|date=2021-05|title=DNA methylation profile of a hepatosplenic gamma/delta T-cell lymphoma patient associated with response to interferon-α therapy|url=https://pubmed.ncbi.nlm.nih.gov/32820235|journal=Cellular & Molecular Immunology|volume=18|issue=5|pages=1332–1335|doi=10.1038/s41423-020-0518-4|issn=2042-0226|pmc=8093208|pmid=32820235}}</ref>
** CpG methylation changes have the potential to serve as biomarkers of drug responses and/or disease progression<ref name=":7" />
**CpG methylation changes have the potential to serve as biomarkers of drug responses and/or disease progression<ref name=":7" />
==Genes and Main Pathways Involved==
==Genes and Main Pathways Involved==
''*SyK'' expression was seen one study, which is not typical for normal T-cells<ref name=":5" />
''*SyK'' expression was seen one study, which is not typical for normal T-cells<ref name=":5" />
* ''Syk'' is a protein tyrosine kinase usually involved in B-cell receptor signaling<ref name=":5" />
*''Syk'' is a protein tyrosine kinase usually involved in B-cell receptor signaling<ref name=":5" />
==Genetic Diagnostic Testing Methods==
==Genetic Diagnostic Testing Methods==