Rare case of CD8+ CD56+ cytotoxic variant of mycosis fungoides clinically presenting with a combination of hypopigmentation and poikiloderma

Primary cutaneous CD8+ cytotoxic T-cell lymphoma of the face with intraoral involvement, presenting facial nerve palsy after chemotherapy

The primary cutaneous (PC) CD8+ T-cell lymphoproliferative disorders (LPDs) comprise clinically and histologically heterogeneous entities including mycosis fungoides, lymphomatoid papulosis, hydroa-vacciniforme-like LPD, subcutaneous panniculitis-like T-cell lymphoma (TCL), PC acral CD8+ TCL, PC CD8+ aggressive epidermotropic cytotoxic TCL, and PC peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS). We describe a 33-year-old man who presented progressive facial swelling and lower lip involvement one year ago. Microscopy revealed an atypical small to medium-sized lymphoid proliferation exhibiting perivascular accentuation, adnexotropism and apoptotic cell debris, without surface epithelium involvement. The tumor cells were positive for CD3, CD8, granzyme B, perforin, MUM1/IRF4, and TCR-BF1. The Ki-67 labeling index was 48%. EBER1/2 was negative. Additional studies confirmed localized disease. The diagnosis favored PC-PTCL-NOS. Two months after completing chemotherapy, right-sided facial nerve palsy was diagnosed. CD8+ T-cell LPDs should be considered in the differential diagnosis when assessing facial swelling with intraoral involvement. This article is protected by copyright. All rights reserved.