title: Folliculotropic T-cell lymphocytosis (mucin-poor follicular mucinosis).
abstract: A 48-year-old man presented with multiple asymptomatic patches of hair loss over his trunk and limbs associated with focal keratotic follicular plugs. Multiple skin biopsies showed a panfollicular lymphocytic infiltrate associated with follicular hyperkeratinization, minimal follicular spongiosis, focal basaloid follicular hyperplasia but no overt follicular mucinosis. The lymphocytes were small and there was no atypia. Immunoperoxidase stains showed that the follicular lymphocytes were T cells and predominantly CD4 positive with HLADr (LN3) expressed on their surface. There were insufficient clinical or histopathological features to make a diagnosis of folliculotropic T-cell lymphoma. This case currently may be classified best as folliculotropic T-cell lymphocytosis and may represent a mucin-poor counterpart of follicular mucinosis. Such cases may pursue an indolent course or may evolve to folliculotropic T-cell lymphoma, mycosis fungoides or anaplastic lymphoma. The term folliculotropic T-cell lymphocytosis may be useful for similar cases lacking clinical or histological criteria for lymphoma and lacking follicular mucinosis.
authors.affiliation: Skin and Cancer Foundation Australia, New South Wales, Australia.
authors.forename: S
authors.initials: S
authors.lastname: Kossard
authors.forename: D
authors.initials: D
authors.lastname: Rubel
mesh_terms: D015496:CD4-Positive T-Lymphocytes / Q000473:pathology; D003937:Diagnosis, Differential; D006684:HLA-DR Antigens / Q000032:analysis; D018859:Hair Follicle / Q000473:pathology*; D006801:Humans; D006965:Hyperplasia; D008218:Lymphocytosis / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D000507:Mucinosis, Follicular / Q000473:pathology*; D013601:T-Lymphocytes / Q000473:pathology*
chemical_list: D006684:HLA-DR Antigens