Mycosis Fungoides in the Pediatric Population: Report from an International Childhood Registry of Cutaneous Lymphoma

Background/Objectives: There are limited data on the clinical presentation and progression of pediatric cutaneous lymphoma. This study focuses on the clinical characteristics of pediatric patients with mycosis fungoides (MF). Materials and Methods: This descriptive study presents clinical characteristics of 22 pediatric patients with MF, enrolled in the international Childhood Registry for Cutaneous Lymphomas (CRCL). Results: The mean ages at onset and at diagnosis were 7.5 (SD 3.8 years) years and 9.9 (SD 3.4) years, respectively. The most common MF presentation was patch stage (68%), followed by hypopigmentation (59%) and plaque stage disease (50%). Epidermotropism and lymphocytic atypia were the most common pathologic features, found in 89% and 85%, respectively. Cerebriform nuclei were noted in 42%, and Pautrier microabscesses were seen in 16% of cases. A cytotoxic pattern was more commonly seen (67% vs 33%), and clonality was detected in 21% (3 of 14) of patients. All patients presented with early-stage disease and received skin-directed therapy (topical steroids, 73%; light therapy, 54%; or combination therapy, 35%). Conclusions: Pediatric patients with MF present in the first decade of life, with early-stage disease and unusual forms such as hypopigmented variant. Further patient enrolment will provide information regarding natural history, treatment response, and overall prognosis of pediatric cutaneous T-cell lymphoma (CTCL).