Fortunately, few cases of primary cutaneous lymphoma and mycosis fungoides (MF) are seen in pediatric patients. In my experience, as head of the Lymphoma Unit at Hospital Universitario Basurto, in Bilbao, Spain, I have seen just 2 cases of MF, both classic, with an onset before the age of 18 years. The course of disease was more aggressive than usual in both patients. One of the patients died at the age of 33 years following allogeneic hematopoietic progenitor cell transplantation and the other developed tumor-stage MF (IIB).

In this issue of Actas Dermo-Sifiliográficas, Bettina Cervini A et al. present 14 cases of MF, most of which were hypopigmented, from a pediatric hospital. I recently had the opportunity to see a similar case in an immigrant girl who had been diagnosed in Columbia. Hypopigmented MF is more common in patients with dark skin (Fitzpatrick skin types iv-v), as evidenced by the literature, and we may therefore see an increasing number of cases in our setting. The main entity that should be contemplated in the differential diagnosis is pityriasis alba. This is a very common condition in pediatric settings, but the possibility of hypopigmented MF needs to be considered in cases that are refractory to treatment or that do not follow a typical course.

Reading this article will help us to do this.