Folliculotropic Mycosis Fungoides: Current Guidance and Experience from Clinical Practice

INTRODUCTION: Folliculotropic mycosis fungoides (FMF) is the most frequent variant of mycosis fungoides (MF), with clinical features which differ from the classic form. As for therapeutic options, the latest guidelines on MF agree on a stage-driven strategy, in consideration of clinical presentation, symptom burden and patient’s comorbidities. MATERIALS AND METHODS: A search on MEDLINE, PubMed, Scopus and Cochrane Library was conducted to gather the latest evidence on FMF clinical management. Manuscripts published in the last five years (January 2017–April 2022) were included. Our single-center experience was also described. RESULTS: A total of 15 articles were analyzed, with a total of 432 patients (disease stage from IA to IVA2). The most widely-used treatment was psoralen ultra-violet A (PUVA) in monotherapy or in association with other drugs. Oral retinoid-based therapy was also described as a therapeutic option alone or in combination. Other therapy reported were based on Brentuximab Vedotin, Mogamulizumab, Carmustine, topical steroids, tazarotene and excimer laser, interferon, nitrogen mustard, imiquimod, systemic chemotherapy, extracorporeal photopheresis and stem cell transplantation. DISCUSSION: FMF is characterized by specific clinical-pathologic features. Advanced forms assume characteristics more similar to classic MF (infiltrated plaques and nodules), whilst early stages can present in a wide range of clinical forms (acneiform lesions, follicular-like keratoses, erythematous patches). As for therapeutic options, in absence of specific guidelines, a high number of treatments are described in clinical practice, with variable results. Phototherapy in all its forms, especially as PUVA, appears to have the greatest initial therapeutic success. Retinoids, although widely used, appear to be poorly effective in monotherapy, particularly acitretin. Combination treatment with phototherapy seems to be advisable. Ionizing treatments, such as radiotherapy and TSEBT, appear effective, at least in the short term. Overall, an integrated approach is mandatory for the inconstant course of the disease and its multidisciplinary nature.