%0 Journal Article
%T Interstitial mycosis fungoides: A rare presentation of mycosis fungoides with overlapping granulomatous and folliculotropic features.
%A Chung C
%A Wu B
%A LeWitt T
%A Griffin T
%A Hooper M
%A Zhou XA
%A Choi J
%A Guitart J
%J J Cutan Pathol
%V 51
%N 6
%D 2024 Jun 5
%M 38443749
%F 1.458
%R 10.1111/cup.14599
%X <B>BACKGROUND: </B>Interstitial mycosis fungoides (IMF) is a rare subtype of mycosis fungoides (MF) characterized by atypical lymphocytes infiltrating the reticular dermis between collagen bundles with limited epidermotropism and variable granulomatous features.<BR><B>METHODS: </B>Retrospective single institution review of 31 cases of IMF including clinical characteristics, disease course and pathological features.<BR><B>RESULTS: </B>Our cohort was predominately male (19; 61%, M:F 1.6:1) with a mean age at diagnosis of 43 years (range 11-85), mean signs/symptoms duration of 7 years prior to diagnosis, and 6 years mean follow-up duration. Clinically, patients often exhibited symmetric ill-defined patches/plaques involving intertriginous regions with tan-yellow hyperpigmentation and follicular-based papules, wrinkling, and alopecia. Lymphadenopathy was noted in seven patients. Fifteen (52%) patients were in near or complete clinical remission at the latest follow-up. T-cell receptor gene rearrangement was positive in 23/24 (96%) cases. Histopathologically, atypical cells were small-medium, CD4+ (29; 94%) or rarely CD4+/CD8+ (1; 3%) lymphocytes infiltrating the reticular dermis with thickened collagen bundles (27; 87%), multinucleated giant cells (12; 39%), and often tracing along adnexa with subtle folliculotropism (12/20; 60%).<BR><B>CONCLUSIONS: </B>Our study demonstrates IMF is an indolent subtype of MF with distinct features, including frequent granulomatous and subtle follicular involvement resulting in alopecia.