Lymphomatoid papulosis: clinicopathological comparative study with pityriasis lichenoides et varioliformis acuta.

We have compared the clinical and histopathological features of 6 patients with lymphomatoid papulosis (LP) and 14 patients with pityriasis lichenoides et varioliformis acuta (PLEVA). There were some differences between the clinical features in the two diseases, including the size and appearance of skin lesions and the duration of the course of disease. Ki-1 Ag positive, large, atypical, lymphoid cells were always seen in lymphomatoid papulosis; none of lymphoid cells of pityriasis lichenoides et varioliformis acuta demonstrated this antigen. We conclude that lymphomatoid papulosis and PLEVA, although sharing some common features, should be considered to be different clinical and immunopathological entities.