{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,10]],"date-time":"2026-09-10T07:38:29Z","timestamp":1789025909145,"version":"build-2803163510"},"reference-count":32,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2025,9,22]],"date-time":"2025-09-22T00:00:00Z","timestamp":1758499200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Korea government (MSIT)","award":["GTL24021-000"],"award-info":[{"award-number":["GTL24021-000"]}]},{"name":"Chungnam National University","award":["GTL24021-000"],"award-info":[{"award-number":["GTL24021-000"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diagnostics"],"abstract":"<jats:p>Background\/Objectives: Angioimmunoblastic T-cell lymphoma (AITL) is a rare peripheral T-cell lymphoma of follicular helper T-cell (TFH) origin, often associated with immune dysregulation and EBV-positive B-cell proliferation. Kaposi sarcoma (KS) is a vascular neoplasm caused by human herpesvirus 8 (HHV-8), typically arising in immunocompromised individuals. The synchronous occurrence of AITL and KS in HIV-negative patients is exceptionally rare, with only three cases previously reported worldwide. Case Presentation: We describe an 81-year-old HIV-negative Korean woman presenting with progressive generalized edema and dyspnea. Imaging revealed multifocal lymphadenopathy. Excisional biopsy of the inguinal lymph node showed two distinct but adjacent neoplastic processes. The AITL component demonstrated a polymorphous infiltrate of atypical TFH cells expressing CD3, CD4, CD10, PD-1, and Bcl-6, with monoclonal TCR-\u03b3 rearrangement and TET2 and RHOA mutations. The KS component comprised spindle cells with slit-like vascular spaces, red blood cell extravasation, and immunoreactivity for HHV-8, CD31, CD34, and ERG. The findings were consistent with a collision tumor. Despite supportive care, the patient\u2019s condition deteriorated, and she was discharged with palliative care. Discussion: The coexistence of AITL and KS in an HIV-negative setting raises important pathogenetic considerations. AITL is characterized by profound immune dysregulation, with depletion of normal T-cell subsets, abnormal B-cell activation, and cytokine milieu changes that may favor latent viral reactivation. This immunologic environment may permit HHV-8 reactivation, thereby facilitating the development of KS even in the absence of overt immunodeficiency due to HIV infection. Our findings support the hypothesis that AITL-related immune dysfunction may create a permissive niche for HHV-8-driven neoplasia. Conclusions: This is the first reported case in Asia and the fourth worldwide of a collision tumor comprising AITL and KS in an HIV-negative patI dient. The case suggests that AITL-associated immune dysregulation may facilitate HHV-8 reactivation and KS development even in the absence of HIV infection. Awareness of this association is critical for accurate diagnosis and optimal patient management.<\/jats:p>","DOI":"10.3390\/diagnostics15182411","type":"journal-article","created":{"date-parts":[[2025,9,22]],"date-time":"2025-09-22T13:04:44Z","timestamp":1758546284000},"page":"2411","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Collision Tumor of Angioimmunoblastic T-Cell Lymphoma and Kaposi Sarcoma in an HIV-Negative Elderly Woman: The First Reported Case in Asia"],"prefix":"10.3390","volume":"15","author":[{"given":"Myung-Won","family":"Lee","sequence":"first","affiliation":[{"name":"Department of Internal Medicine, Chungnam National University Hospital, 282 Munhwa-ro, Jung-gu, Daejeon 35015, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0905-9730","authenticated-orcid":false,"given":"Jin-Man","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Pathology, Chungnam National University College of Medicine, 266 Munwha-ro, Jung-gu, Daejeon 35015, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,9,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1720","DOI":"10.1038\/s41375-022-01620-2","article-title":"The 5th edition of the World Health Organization Classification of Haematolymphoid Tumours: Lymphoid Neoplasms","volume":"36","author":"Alaggio","year":"2022","journal-title":"Leukemia"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1229","DOI":"10.1182\/blood.2022015851","article-title":"The International Consensus Classification of Mature Lymphoid Neoplasms: A report from the Clinical Advisory Committee","volume":"140","author":"Campo","year":"2022","journal-title":"Blood"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"218","DOI":"10.1007\/s10238-025-01754-4","article-title":"Angioimmunoblastic T-cell lymphoma: A concise overview encompassing the pathogenetic, pathological, clinical, therapeutical characteristics, and recent advances","volume":"25","author":"Feng","year":"2025","journal-title":"Clin. Exp. Med."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"627","DOI":"10.1182\/blood.V99.2.627","article-title":"Neoplastic T cells in angioimmunoblastic T-cell lymphoma express CD10","volume":"99","author":"Attygalle","year":"2002","journal-title":"Blood"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"510","DOI":"10.1080\/15321819.2014.1001031","article-title":"Is CD10 antibody useful in the diagnosis of angioimmunoblastic T-cell lymphoma?","volume":"36","author":"Mlika","year":"2015","journal-title":"J. Immunoass. Immunochem."},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Wang, C., Zhu, L., Liu, S., Yi, S., Xiao, M., Zhang, Y., and Mao, X. (2022). PD-1 combined with TRBC1 and pan-T cell antibodies for robustly monitoring angioimmunoblastic T-cell lymphoma. Front. Med., 9.","DOI":"10.3389\/fmed.2022.962428"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1093\/ajcp\/aqab090","article-title":"How I Diagnose Angioimmunoblastic T-Cell Lymphoma","volume":"156","author":"Xie","year":"2021","journal-title":"Am. J. Clin. Pathol."},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Hu, L., Zhang, X., Li, H., Lin, S., and Zang, S. (2022). Targeting TET2 as a Therapeutic Approach for Angioimmunoblastic T Cell Lymphoma. Cancers, 14.","DOI":"10.3390\/cancers14225699"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"431","DOI":"10.1016\/j.clml.2021.03.002","article-title":"Clinicopathological Implications of RHOA Mutations in Angioimmunoblastic T-Cell Lymphoma: A Meta-analysis: RHOA mutations in AITL","volume":"21","author":"Nguyen","year":"2021","journal-title":"Clin. Lymphoma Myeloma Leuk."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"371","DOI":"10.1038\/ng.2916","article-title":"A recurrent inactivating mutation in RHOA GTPase in angioimmunoblastic T cell lymphoma","volume":"46","author":"Yoo","year":"2014","journal-title":"Nat. Genet."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"9","DOI":"10.1038\/s41572-019-0060-9","article-title":"Kaposi sarcoma","volume":"5","author":"Cesarman","year":"2019","journal-title":"Nat. Rev. Dis. Primers"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"783","DOI":"10.2340\/1651-226X.2024.40537","article-title":"Classic Kaposi sarcoma: Diagnostics, treatment modalities, and genetic implications\u2014A review of the literature","volume":"63","author":"Batash","year":"2024","journal-title":"Acta Oncol."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"oyaf024","DOI":"10.1093\/oncolo\/oyaf024","article-title":"Fifth subtype of Kaposi sarcoma in HIV-negative MSM: A retrospective single-arm cohort study from a tertiary care center in NYC from 2000 to 2022","volume":"30","author":"Morales","year":"2025","journal-title":"Oncologist"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"556","DOI":"10.1111\/his.15083","article-title":"Angioimmunoblastic T-cell lymphoma and Kaposi sarcoma: A fortuitous collision?","volume":"84","author":"Poullot","year":"2024","journal-title":"Histopathology"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"5010","DOI":"10.4049\/jimmunol.178.8.5010","article-title":"Germinal center helper T cells are dual functional regulatory cells with suppressive activity to conventional CD4+ T cells","volume":"178","author":"Marinova","year":"2007","journal-title":"J. Immunol."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"95","DOI":"10.1056\/NEJMc1111708","article-title":"TET2 and DNMT3A mutations in human T-cell lymphoma","volume":"366","author":"Couronne","year":"2012","journal-title":"N. Engl. J. Med."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1901","DOI":"10.1182\/blood-2011-11-391748","article-title":"IDH2 mutations are frequent in angioimmunoblastic T-cell lymphoma","volume":"119","author":"Cairns","year":"2012","journal-title":"Blood"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"104294","DOI":"10.1016\/j.yexmp.2019.104294","article-title":"RHOA G17V mutation in angioimmunoblastic T-cell lymphoma: A potential biomarker for cytological assessment","volume":"110","author":"Lee","year":"2019","journal-title":"Exp. Mol. Pathol."},{"key":"ref_19","first-page":"1166","article-title":"Lymph node involvement in classic Kaposi sarcoma: Report of three cases","volume":"135","author":"Mohanna","year":"2007","journal-title":"Rev. Med. Chile"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"23","DOI":"10.1016\/j.humpath.2005.08.020","article-title":"Kaposi\u2019s sarcoma-associated herpesvirus\/human herpesvirus 8 infection in reactive lymphoid tissues: A model for KSHV\/HHV-8-related lymphomas?","volume":"37","author":"Lazzi","year":"2006","journal-title":"Hum. Pathol."},{"key":"ref_21","first-page":"127","article-title":"Multicentric Castleman\u2019s disease, non-Hodgkin\u2019s lymphoma, and Kaposi\u2019s sarcoma: A rare simultaneous occurrence","volume":"20","author":"Sukpanichnant","year":"2002","journal-title":"Asian Pac. J. Allergy Immunol."},{"key":"ref_22","first-page":"73","article-title":"Simultaneous lymph node involvement by Castleman disease and Kaposi sarcoma","volume":"33","author":"Pinto","year":"2011","journal-title":"Rev. Bras. Hematol. Hemoter."},{"key":"ref_23","first-page":"004876","article-title":"Coexistence of HHV-8-Associated Plasmacytic Multicentric Castleman Disease, Kaposi\u2019s Sarcoma, and Multiple Myeloma in a HIV-Negative Patient","volume":"11","author":"Ismayilov","year":"2024","journal-title":"Eur. J. Case Rep. Intern. Med."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"626","DOI":"10.1136\/jcp.2004.023465","article-title":"KSHV\/HHV-8 associated Kaposi\u2019s sarcoma in lymph nodes concurrent with Epstein-Barr virus associated Hodgkin lymphoma","volume":"58","author":"Carbone","year":"2005","journal-title":"J. Clin. Pathol."},{"key":"ref_25","first-page":"201","article-title":"Simultaneous occurrence of Kaposi\u2019s sarcoma and nodular lymphocyte predominant subtype of Hodgkin\u2019s lymphoma in the same lymph node","volume":"26","author":"Kankaya","year":"2009","journal-title":"Turk. J. Haematol."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"62","DOI":"10.1177\/1066896918762053","article-title":"Kaposi Sarcoma With Coexisting Intravascular Lymphoma","volume":"27","author":"Ashman","year":"2019","journal-title":"Int. J. Surg. Pathol."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"645","DOI":"10.1182\/blood.V88.2.645.bloodjournal882645","article-title":"Primary effusion lymphoma: A distinct clinicopathologic entity associated with the Kaposi\u2019s sarcoma-associated herpes virus","volume":"88","author":"Nador","year":"1996","journal-title":"Blood"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"47","DOI":"10.1159\/000102587","article-title":"Non-Hodgkin lymphomas concurrent with HHV8-associated Kaposi\u2019s sarcoma in the same lymph node in AIDS and non-AIDS patients","volume":"118","author":"Licci","year":"2007","journal-title":"Acta Haematol."},{"key":"ref_29","first-page":"74","article-title":"Diffuse large B-cell lymphoma concurrent with Kaposi\u2019s sarcoma in the same lymph node in a human immunodeficiency virus-negative patient","volume":"65","author":"Nakashima","year":"2024","journal-title":"Rinsho Ketsueki"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"1582","DOI":"10.1002\/1097-0142(19841015)54:8<1582::AID-CNCR2820540819>3.0.CO;2-W","article-title":"Kaposi\u2019s sarcoma and angioimmunoblastic lymphadenopathy","volume":"54","author":"Varsano","year":"1984","journal-title":"Cancer"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"617","DOI":"10.1111\/j.1440-1827.2006.02017.x","article-title":"Distinct expression of Kaposi\u2019s sarcoma-associated herpesvirus-encoded proteins in Kaposi\u2019s sarcoma and multicentric Castleman\u2019s disease","volume":"56","author":"Abe","year":"2006","journal-title":"Pathol. Int."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"802","DOI":"10.1097\/01.pas.0000209855.28282.ce","article-title":"Programmed death-1 (PD-1) is a marker of germinal center-associated T cells and angioimmunoblastic T-cell lymphoma","volume":"30","author":"Dorfman","year":"2006","journal-title":"Am. J. Surg. Pathol."}],"container-title":["Diagnostics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2075-4418\/15\/18\/2411\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T18:47:09Z","timestamp":1760035629000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2075-4418\/15\/18\/2411"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,9,22]]},"references-count":32,"journal-issue":{"issue":"18","published-online":{"date-parts":[[2025,9]]}},"alternative-id":["diagnostics15182411"],"URL":"https:\/\/doi.org\/10.3390\/diagnostics15182411","relation":{},"ISSN":["2075-4418"],"issn-type":[{"value":"2075-4418","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,9,22]]}}}