Mycosis Fungoides: A Review of Clinical Findings

Abstract

Mycosis fungoides (MF) is defined as an epidermotropic primary cutaneous T-cell lymphomas characterized by T-helper phenotype T-lymphocytes with small to medium-sized cerebriform nuclei (though cytotoxic variants are not uncommon). MF is limited to the skin and can exhibit extracutaneous spread (lymph nodes, visceral organs) in advanced stages. The 2018 World Health Organization-European Organization for Research and Treatment of Cancer (WHO-EORTC) classification recognizes the classical Alibert-Bazin MF type, as well as folliculotropic mycosis fungoides, pagetoid reticulosis, and granulomatous slack skin MF subtypes, which were first included in the 2005 WHO-EORTC classification. In addition to classical MF and its three variants, other clinicopathologic subtypes of MF have been described, including hypopigmented, poikilodermatous, erythrodermic, granulomatous, hyperpigmented, ichthyosiform, syringotropic, papular, purpuric, interstitial, pustular, bullous, verrucous, and psoriasiform MF. These subtypes exhibit clinical features similar to the diseases they mimic. It is essential to recognize the clinical features of both classical and variant forms of MF for early diagnosis and to consider the possibility of MF in the differential diagnosis. Dermatologists need to increase their awareness regarding this topic. This review discusses the clinical findings and variants of MF and highlights the key points of the diagnosis and treatment process.