Mycosis fungoides and Sézary syndrome

Abstract

Mycosis fungoides (MF) and Sézary syndrome (SS) are a distinct disease entity of cutaneous T-cell lymphoma with heterogenous clinical features and prognosis. MF mainly involves skin and usually shows an indolent and favorable clinical course. In patients with advanced-stage disease, extracutaneous involvement including lymph nodes, viscera, and blood, or large cell transformation may be observed. SS is a leukemic form of advanced-stage MF, characterized by generalized erythroderma. Early-stage MF can be treated with skin-directed therapy. However, patients with refractory or advanced-stage disease are associated with severe symptoms or poor prognosis, requiring systemic therapy. Recent progress in understanding the pathogenesis of MF/SS has contributed to advances in the management of these rare diseases. This review aims to describe the clinical manifestations, diagnosis, risk stratification, and treatment strategy of MF/SS, focusing on the recent updates in the management of these diseases.

Keywords: Cutaneous T-cell lymphoma; Diagnosis; Mycosis fungoides; Prognosis; Sézary syndrome; Treatment.

Fig. 1

Clinical manifestation and pathologic findings. Patchy (A), plaque (B), and tumor-type (C) skin lesions in a patient with advanced stage mycosis fungoides. PET scan showed FDG-uptake on large extent plaque and tumor stage lesions and axillary lymph nodes (D). Histology of plaque-type MF lesion with epidermotropic infiltration of lymphocytes, in which clonality of TCR gene rearrangement was confirmed (E). Higher resolution of E, representing grouped aggregation of large lymphocytes in the epidermis, forming early form of Pautrier’s micro-abscess (F). Generalized erythroderma in a patient with Sézary syndrome (G). Atypical lymphocyte with cerebriform nuclei, so called ‘Sézary cell’, was observed on peripheral blood smear (H).

Fig. 2

Therapeutic options for mycosis fungoides and Sézary syndrome based on the stage of disease.