Weill Cornell Medicine- New York Presbyterian Hospital, Department of Dermatopathology, 1300 York Avenue, New York, NY 10065, United States of America.
Weill Cornell Medicine- New York Presbyterian Hospital, Hematology/Oncology, 1300 York Avenue, New York, NY 10065, United States of America.
Ann Diagn Pathol. 2019 Jun;40:94-104. doi: 10.1016/j.anndiagpath.2019.04.013. Epub 2019 Apr 26.
There is a growing recognition that some primary cutaneous T cell lymphomas of the skin exhibit a follicular helper T cell phenotype best exemplified by primary cutaneous CD4+ small/medium sized pleomorphic T cell lymphoma. The follicular helper T cells is an evolutionary function in a common TH1 cell under the influence of other cell types most notably monocyte derived dendritic cells but also plasma cells. In addition, the skin defines a characteristic organ site of involvement for angioimmunoblastic T-cell lymphoma (AITL); the first recognized form of follicular helper T cell lymphoma. One of the hallmarks of the follicular helper T cell lymphomas a significant degree of post germinal center B cell hyperplasia. We encountered 7 cases of primary cutaneous follicular helper T cell and four cases of AITL, in which the biopsies contained a light chain restricted plasma cell infiltrate in the skin. There were no features that suggested an atypical or more aggressive clinical course in association with the identification of this light chain restricted plasmacytic infiltrates except one case of AITL in whom a diffuse large cell B cell lymphoma subsequently developed. There was no association with Epstein-Barr virus (EBV) infection light chain restricted plasma cell infiltrate in any of the eleven cases. The basis of these infiltrates is likely a reciprocal functional one reflecting the role of follicular helper T cells in the induction of B cell hyperplasia and the role of plasma cells as a countercheck balance controlling the extent of follicular helper T cell hyperplasia. B cell clonality, plasma cell atypia and blastic B cell transformation can occur without implying a malignant transformation.
越来越多的人认识到，一些皮肤原发性 T 细胞淋巴瘤表现出滤泡辅助 T 细胞表型，以原发性皮肤 CD4+小/中大型多形性 T 细胞淋巴瘤为最佳代表。滤泡辅助 T 细胞是在其他细胞类型（尤其是单核细胞衍生的树突状细胞，但也包括浆细胞）影响下 TH1 细胞的一种进化功能。此外，皮肤是血管免疫母细胞性 T 细胞淋巴瘤（AITL）的特征性受累器官部位；这是滤泡辅助 T 细胞淋巴瘤的第一个公认形式。滤泡辅助 T 细胞淋巴瘤的一个标志是生发中心后 B 细胞高度增生。我们遇到了 7 例原发性皮肤滤泡辅助 T 细胞淋巴瘤和 4 例 AITL，其中活检显示皮肤中有轻链限制性浆细胞浸润。除了 1 例 AITL 随后发展为弥漫性大 B 细胞淋巴瘤外，这些轻链限制性浆细胞浸润与提示非典型或更具侵袭性临床过程的特征无关。在这 11 例病例中，均未发现与 EBV 感染有关的轻链限制性浆细胞浸润。这些浸润的基础可能是一种相互的功能反应，反映了滤泡辅助 T 细胞在诱导 B 细胞增生中的作用以及浆细胞作为一种制衡平衡控制滤泡辅助 T 细胞增生程度的作用。B 细胞克隆性、浆细胞异型性和母细胞性 B 细胞转化可能发生而不暗示恶性转化。
