CONTINUING MEDICAL EDUCATION Cutaneous T-cell lymphoma in skin of color Ginette A. Hinds, MD, a and Peter Heald, MD a,b New Haven, Connecticut Over the past three decades, there has been a marked increase in the incidence of cutaneous T-cell lymphoma (CTCL), with significant differences in the rates of CTCL by race and ethnicity. The overall incidence of CTCL has been shown to be higher among blacks than among whites and other racial groups. In addition, CTCL is thought to follow a more aggressive course in black patients. This article highlights the differences in clinical appearance and response to therapy, and discusses the differential diagnosis of CTCL in skin of color in an attempt to ensure earlier diagnosis and better outcomes for these patients. ( J Am Acad Dermatol 2009;60:359-75.) Learning objective: After completing this learning activity, participants should be able to recognize and diagnose cutaneous T-cell lymphoma (CTCL) in skin of color, describe the unique aspects of diagnosis and management of CTCL in skin of color, and discuss the differential diagnosis of CTCL. C utaneous T-cell lymphomas are a group of diseases unified by several features, includ- ing the proliferation of skin homing T-cells in the skin, the monoclonal nature of these T-cells, and the potential of almost all forms of CTCL to transform into high grade T-cell lymphoma. 1,2 The two broad categories of CTCLs are MF/Se ´zary syn- drome and non-MF CTCLs. This initial separation is driven by the more common occurrence of MF over the non-MF CTCLs. For clinicians, there are very few distinctive clinical features of the non-MF CTCLs. They are diagnosed and classified based on histologic criteria currently defined by the World Health OrganizationeEuropean Organisation for Research and Treatment of Cancer (WHO-EORTC) classification. 3 The pathogenesis of MF involves the epidermot- ropism of malignant lymphocytes. 2 The intermin- gling of these malignant cells and the pigmentary system in the skin produces unique diagnostic clues, therapeutic considerations, and monitoring maneu- vers that are distinct from MF in pigmented skin. This review emphasizes the unique clinical features of MF in skin of color in order to improve recognition and management. PRESENTATION AND DIAGNOSIS There are three common and often intertwined presentations of MF in skin of color. First, the dyspigmentation associated with MF can produce asymptomatic hypopigmented (Figs 1 and 2) and hyperpigmented (Figs 3 and 4) lesions. In addition, some patients may present with lesions that mimic a more common dermatosis, such as psoriasis, atopic dermatitis, vitiligo, or lichen planus. The third pre- sentation involves pruritus and secondary lichenifi- cation and hyperpigmentation, which often masks clues to the presence of MF. In addition, there are several clinical syndromes that mimic MF in skin of color, and these conditions must be excluded before the diagnosis of MF is established (Table I). The early diagnosis of MF is important because the appropriate management of stage IA (discussed later) disease portends a prognosis similar to indi- viduals without MF. 4 The early recognition and diagnosis of MF in skin of color is facilitated by a correlation of clinical and histologic findings, and Abbreviations used: ATL: adult T-cell leukemia CTCL: cutaneous T-cell lymphoma LPPI: lichen planus pigmentosus LyP: lymphomatoid papulosis MF: mycosis fungoides PMH: progressive macular hypomelanosis SUV: standardized uptake value TSEB: total skin electron beam From the Department of Dermatology a and the Yale Comprehen- sive Cancer Center, b Yale University School of Medicine. Funding sources: None. Conflicts of interest: None declared. Reprint requests: Ginette A. Hinds, MD, Department of Dermatology, Yale University School of Medicine, 333 Cedar St, LCI 501, New Haven, CT 06515. E-mail: ginette.hinds@yale. edu. 0190-9622/$36.00 ª 2008 by the American Academy of Dermatology, Inc. doi:10.1016/j.jaad.2008.10.031 359