Mycosis fungoides with onset before 20 years of age

Background: Recent identification of mycosis fungoides (MF) in a man in whom the diagnosis was established at age 22 months prompted us to evaluate our experience with early onset MF. Objective: Our purpose was to summarize the clinical characteristics and course of 24 patients in whom MF began by history before age 20 years and was confirmed by biopsy in 13 by that time. Methods: A retrospective study was conducted. Results: All 24 patients had patch/plaque disease and represented 4.3% of the 557 patients with cutaneous T-cell lymphoma seen by us since 1971. None progressed to a more advanced stage in up to 24 years (median, 12 years) after histologic diagnosis. Five patients (21%) presented with hypopigmentation. Conclusion: Early onset MF is not more aggressive than that appearing in adult life. MF should be considered in the differential diagnosis of chronic dermatoses in young persons, particularly in those presenting with hypopigmentation.