Mycosis fungoides beyond the classical Alibert-Bazin disease: report of seventeen atypical variants

Resumen

ABSTRACT
Introduction: mycosis fungoides (MF) is the most common subtype of cutaneous T-cell lymphomas (CTCL). Clinicopathological manifestations in the classic form of the disease are multiple patches and plaques that may progress to tumor stage. Many variants of this CTCL differ substantially from this presentation and therefore are referred to as atypical or unusual variants, most of them resembling other dermatological diseases.
Objective: to evaluate the relative frequency of rare variants of MF and to estimate the clinical course of these forms in relation to their stage at the time of diagnosis, prognosis and response to treatment.
Design: observational, retrospective and descriptive.
Material and methods: we reviewed our files of patients with primary cutaneous lymphomas (PCL) assisted between November 1995 and July 2007. We included all patients with clinical, histopathological and immunophenotypic diagnosis which could be included in the categories of the WHO/EORTC classification. We recorded age, sex, date of definitive diagnosis, treatment and clinical course.
Results: we analyzed 93 PCL, of which 89 were CTCL. Of them, 68 (73,12%) were MF - 40 male and 28 female. The mean age at diagnosis was 53,9 years (range: 13 - 78 years). From this total 17 (25%) were atypical variants – 11 were male and 6 were female – with a mean age of 51 years (range: 13 - 78 years). The mean follow-up period after diagnosis of the MF variants was 21,94 months (range: 4 - 102 months). These cases included 5 folliculotropic MF, 4 erythrodermic MF, 3 poikilodermic MF, 2 hypopigmented MF, 1 granulomatous slack skin, 1 ichthyosiform MF and 1 unilesional MF. Most of the patients were treated with a combined regimen that included IFN and PUVA, with complete remission in 53%. We observed one case of folliculotropic MF with progressive disease and visceral involvement.
Conclusions: it is important to recognize these atypical variants of MF, due to their similarity to other inflammatory dermatoses, posing their correct diagnosis a real challenge. Misdiagnosis in the early stages will delay the correct diagnosis and prompt treatment, which are directly related to their prognosis
(Dermatol Argent 2008;14(2):124-133).

Key words: mycosis fungoides; atypical variants.