Mycosis fungoides in Patients under 20 Years of Age: Report of 7 Cases, Review of the Literature and Study of the Clinical Course

Background:Mycosis fungoides (MF) is rare in young patients. Its clinical behavior is still uncertain, as some reports have suggested that it has a more aggressive course than does the adult-onset type. Aim:To ascertain if early-onset MF represents a heterogeneous group of cutaneous T cell lymphomas. Materials and Methods:Clinical, immunohistopathological and follow-up data of early-onset (<20 years of age) MF cases reported in the literature (n = 42) plus 7 described herein were compared with those of a cohort of adult-onset MF patients (n = 252) diagnosed at our institution since 1975. Results:The majority of the 49 early-onset MF patients had patch-plaque stage disease at diagnosis. Ten had hypopigmented lesions. The predominant phenotype was CD3+ CD4+CD7–CD8–. Seven patients had a stage progression, 6 with extracutaneous involvement. Five- and 10-year survival rates were 93 and 74%, respectively. Conclusions:No statistically significant differences were found in the disease course between early- and adult-onset MF.