Mucin‐poor follicular mycosis fungoides

Abstract

A 49-year-old woman was admitted with generalized pruritus which she had for the last 4 years.Three months ago she developed erythema on her face, alopecia totalis, an erythematous macular eruption with follicular hyperkeratoses on the trunk and limbs (Fig. 1). She had bilateral palpable axillary lymphadenopathy. Histologic examination of the biopsies taken from the erythematous areas on the trunk and scalp revealed a folliculocentric infiltration composed of atypical, small and medium-sized mononuclear cells, intermingled with reactive lymphocytes, histiocytes, plasmocytes, rare eosinophils, and giant cells without involvement of the epidermis (Fig. 2). The infiltrate surrounded and invaded the hair follicle epithelium without destroying it.With alcian blue staining, only small amounts of mucin were detected within the epithelium of the hair follicles. By the immunohistochemistry performed, folliculocentric infiltration was mainly composed of CD3(+), CD4(+), CD8(-) lymphocytes. A full blood count, peripheral smear, erythrocyte sedimentation rate (ESR), the concentration of nitrogen in the form of urea in the blood (BUN), creatinin, transaminases, serum electrolytes, C-reactive protein (CRP), IgE, serum lipids, serum lactate dehydrogenase, urinalysis, roentgenogram and CT scan of chest were normal. Beta 2 microglobulin was 3.15 mg / L (normal range 1.2-2.5 mg / L). In the biopsy of the axillary lymph node, there was a focal infiltration of atypical T-cells in the interfollicular area. She was given psoralen-UVA (PUVA) treatment for 6 months (85 sessions, in escalating doses with a total 71.8 j / cm 2 ) which resulted in a partial healing of the pruritus, erythematous plaques, follicular hyperkeratoses, and patchy hair regrowth. She then received oral methyl prednisolone, 40 mg daily for 3 weeks and the dose was gradually decreased and eventually reduced to 16 mg daily in 2 months. This resulted in healing of the pruritus, improvement in the erythematous plaques and follicular hyperkeratoses and axillary lymphadenopathy. Beta 2 microglobulin levels decreased to normal range (2.27 mg / L). After taking the 16 mg daily dose of the prednisolone for 6 months, her complaint of itching recurred. Erythematous plaques and follicular hyperkeratoses were noted again. The dosage of the steroids was increased to 40 mg daily and PUVA treatment was restarted. She is currently receiving oral methyl prednisolone and PUVA. DiscussionCutaneous T-cell lymphoma (CTCL) many have heterogeneous clinical and histological features. A rare form of CTCL, follicular mycosis fungoides (FMF), first described by Peroya et al. in 1997, is an entity differing from alopecia mucinosa / follicular mucinosis associated with mycosis fungoides with regard to its clinical presentation and histology. Follicular mycosis fungoides is a rare variant of cutaneous T-cell lymphoma, histologically characterized by infiltrates of atypical CD4+ lymphocytes around and within the epithelium of the hair follicles. 1-3 The recently described two main criteria for FM...

Clinicopathological spectrum of mycosis fungoides

“…Follicular MF has been described in the literature under various designations, including folliculotropic MF, pilotropic MF, folliculocentric MF, MF-associated follicular mucinosis. [39][40][41][42][43][44][45][46][47][48][49][50] Some authorities believe that the latter should be distinguished from follicular MF. However, we agree with others in that follicular MF and MF-associated follicular mucinosis belong to the spectrum of MF with a predilection for hair follicles.…”

“…Follicular MF has been described in the literature under various designations, including folliculotropic MF, pilotropic MF, folliculocentric MF, MF‐associated follicular mucinosis 39–50 . Some authorities believe that the latter should be distinguished from follicular MF.…”

Folliculotropic T-Cell Lymphocytosis as a Distinct Form of Pilotropic T-Cell Dyscrasia

“…The background population is polymorphous in follicular MF with tissue eosinophilia, neutrophilia, and granulomatous foci. The depth of infiltration needs to be emphasized, 18,[22][23][24][25][26][27][28][29][30][31] as in follicular MF the infiltrates are deeper-seated and surround and permeate the follicle below the entry of the sebaceous gland, often with syringotropism and distinct follicular epithelial hyperplasia. 29 Monoclonality is more commonly observed in follicular MF compared with folliculotropic T-cell lymphocytosis, and the clinical manifestations of follicular MF can be dramatic, ie, as boggy infiltrative plaques and nodules devoid of hair with comedone-like hyperkeratotic follicular lesions.…”