Clonal B‐cell proliferations developing in the background of primary cutaneous CD4+ small/medium T‐cell lymphoproliferative disorder: A case series

• Published in: Journal of cutaneous pathology Vol. 49; no. 11; pp. 971 - 977
• Main Authors: Ates Ozdemir, Deniz, Akdoğan, Neslihan, Okay, Müfide, Uner, Aysegül, Saglam, Arzu
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.11.2022; Wiley Subscription Services, Inc
• Subjects: B‐cell clonal population; CD4 antigen; Cell proliferation; EBV positivity; Hybridization; Lymphocytes; Lymphoma; primary cutaneous CD4+ small/medium lymphoproliferative disorder
• DOI: 10.1111/cup.14296
• ISSN: 0303-6987

Clonal B‐cell proliferations and B‐cell lymphomas may co‐occur in the background of follicular helper T‐cell (TFH)‐derived lymphomas, most associated with EBV, which has been a well‐known fact for many years in the prototypical entity “TFH lymphoma, angioimmunoblastic‐type.” Primary cutaneous CD4+ small/medium T‐cell lymphoproliferative disorder (CD4+ PCSM‐LPD) is also a TFH‐derived clonal proliferation. We searched the archives and identified four cases of CD4+ PCSM‐LPD with accompanying clonal B‐cell proliferation (one of which showed EBER positivity), and one longstanding case of CD4+ PCSM‐LPD, in the background of which a B‐cell lymphoma had developed. These five cases broaden experience on CD4+ PCSM‐LPD with accompanying B‐cell proliferations and also support routine evaluation of these cases with EBV in situ hybridization, to better determine whether or not there is an association with EBV.