Figure 2
From: Deciphering the spectrum of cutaneous lymphomas expressing TFH markers
Histological presentation of a primary cutaneous marginal zone lymphoma (MZL, case no 2) with significant TFH hyperplasia, illustrating the diagnostic difficulty between SMLPD and MZL. (A) (Hematoxylin–Eosin-Saffron (HES), ×10): Nodular and diffuse architecture involving all the dermis, well separated from the epidermis by a “grenz-zone”; (B) (HES, ×20): Small hyperchromatic cells; (C) (CD20, ×5) and (D) (CD4, × 5): The infiltrate is composed of admixed B-cells (50%) and CD4+ T-cells (50%) ; (E) (PD1, ×10) and (F) (CXCL13, ×20): Strong expression of TFH markers in the microenvironnement (PD1: 80%, CXCL13: 25%); (G) (CD23, ×20): Absence of residual CD23+ follicular dendritic cells network; (H,I) (kappa and lambda, ×20); Plasma cells were few (< 10%) but presented a kappa monotypia. The diagnosis of MZL was confirmed thanks to molecular data; the presence of a monoclonal B-cell population, and pathogenic variants of ITPKB, NOTCH2, TNFAIP3, and KMT2D genes using TNGS.
