Lymphomatoid papulosis.

Lymphomatoid papulosis (LyP) is a non-aggressive skin disorder characterized by papulonodular injuries, sometimes necrotic, often scattered, relapsing, which frequently regress spontaneously. LyP represents about 12% of cutaneous lymphomas. The etiology of LyP is unknown. Based on its histopathology, in 2018, the World Health Organization (WHO) classified LyP into six types with similar prognosis (A,B,C,D,E and DUSP22). Once the diagnosis of LyP has been made, having an excellent prognosis, this pathology must be managed mainly with a "watch and wait" strategy. Treatment should be given only in the presence of diffuse, symptomatic lesions with disfiguring evolution, with the aim of reducing time of resolution and preventing recurrences or the formation of new lesions.