LYP. Lymphomatoid papulosis (LyP) is a chronic papulonodular skin disease characterized by recurrent crops of pruritic papules at different stages of development that predominantly arise on the trunk and limbs. There is an increased frequency of prior, coexisting or subsequent lymphoproliferative disorders: this is most commonly mycosis fungoides or Hodgkin lymphoma. LyP has an excellent prognosis. The neoplastic cells in LyP types A and C are CD30+, CD3+, CD4+, CD8− (only rarely the neoplastic cells are CD8+ and CD4-). CD30+ large cells are rare in LyP type B.