Hypopigmented mycosis fungoides: an important differential diagnosis of hypochromias in childhood.

Objective: To highlight the importance of early recognition of hypopigmented mycosis fungoides (HMF) in cases of cutaneous hypochromia in children, with a view to an effective diagnostic and therapeutic approach.

Case description: Two cases of HMF in children are reported. The first case involves an eight-year-old boy with hypochromic macules on the trunk and root of the upper and lower limbs, while the second case is a six-year-old boy with widespread hypochromic patches. Both patients presented with prolonged evolution of hypopigmentation, leading to the suspicion of HMF after excluding other differential diagnoses. Histopathological and immunohistochemical tests were fundamental in confirming the diagnosis of HMF.

Comments: HMF is a less prevalent and less publicized form of mycosis fungoides and is more common in children and people with a high phototype. Its diagnosis is challenging and often requires multiple biopsies for confirmation. Treatment includes phototherapy and immunosuppressive therapy, depending on the patient's age and extent of lesions. Early recognition of HMF is crucial for proper management and to avoid complications associated with malignant evolution.