Syringotropic Mycosis Fungoides: A Variant of Folliculotropic or a Distinct Subtype of Adnexotropic Mycosis Fungoides?

Abstract

Mycosis fungoides (MF) is a slowly progressive form of cutaneous T-cell lymphomas (CTCL). MF is classified into 4 subtypes including folliculotropic MF (FMF). Infiltration of both hair follicles and eccrine glands is included in the FMF classification and designated as syringotropic MF (STMF), an exceedingly rare form of CTCL. We report an additional case of STMF. The clinical course of syringotropic CTCL is more benign than FMF, suggesting that despite similar clinical presentations, they are molecularly distinct diseases. Clinical characteristics can help differentiate STMF from FMF. Skin-directed therapies are less effective in STMF than FMF. With distinct clinical characteristics, histopathologic findings, and disease course, syringotropic CTCL should be considered a subtype entity in the spectrum of adnexotropic MF. J Drugs Dermatol. 2022;21(12):1362-1364. doi:10.36849/JDD.6779.