A Practical Approach to Accurate Classification and Staging of Mycosis Fungoides and Sézary Syndrome

Bjorn Rhys Thomas, MBBS; Sean Whittaker, MB, MD, FRCP


Skin Therapy Letter. 2012;17(10) 

In This Article

Abstract and Introduction


Cutaneous T-cell lymphomas are rare, distinct forms of non-Hodgkin's lymphomas. Of which, mycosis fungoides (MF) and Sézary syndrome (SS) are two of the most common forms. Careful, clear classification and staging of these lymphomas allow dermatologists to commence appropriate therapy and allow correct prognostic stratification for those patients affected. Of note, patients with more advanced disease will require multi-disciplinary input in determining specialist therapy. Literature has been summarized into an outline for classification/staging of MF and SS with the aim to provide clinical dermatologists with a concise review.


Primary cutaneous lymphomas (PCL) are rare forms (2%) of non-Hodgkin's lymphomas with an annual incidence of 0.3–1 per 100,000.[1] These lymphomas include both primary cutaneous T-cell (75%) and B-cell lymphomas defined by presentation at the time of diagnosis without any extracutaneous sites of disease.1 In 2005, the two classification systems for cutaneous T-cell lymphoma (CTCL), namely the World Health Organization (WHO) and European Organization for Research and Treatment of Cancer (EORTC), were combined, providing distinct subtypes based on clinico-pathologic criteria (Table 1).[1,2]

Mycosis fungoides (MF) represents the most common variant of CTCL[3] and is characterized by a monoclonal proliferation of epidermotropic CD4+/CD45RO+ T-cells often with aberrant expression of mature T-cell antigens.[1,4] MF (Alibert-Bazin type) is characterized by the presence of polymorphic patches, plaques, and tumors.[1] Sézary syndrome (SS) is a rare CTCL variant closely related to MF and has classically been described as a triad of erythroderma, generalized lymphadenopathy and Sézary cells (atypical neoplastic T lymphocytes with hyperconvoluted cerebriform nuclei) in the skin, blood, and lymph nodes.[1,5,6] The WHO-EORTC system currently distinguishes SS as a separate entity from MF, but rare cases of SS preceded by typical MF have been described.[3,7]

In this article, we will focus primarily on the evaluation and classification of these conditions and summarize the available therapies.