B-cell differentiation pattern of cutaneous lymphomas in infancy and childhood.

This article documents four children with cutaneous lymphomas. Two of them had regional disease and the other two already had disseminated disease when they were diagnosed. Immunophenotyping of the lymphomatous infiltration disclosed a cell antigen profile with pre-pre-B (HLA-DR+, CALLA+, VIB-C5+), pre-B (HLADR+, CALLA+, VIB-C5+, cytoplasmatic immunoglobulin+), and transitional pre-B characteristics (HLA-DR+, CALLA+, VIB-C5+, surface immunoglobulin+). The morphology of the blast cells in all patients showed features of lymphoblastic lymphoma. Two patients had the convoluted cell type in common, but they were immunologically different, one displaying pre-pre-B and the other pre-B immunophenotypes. The remaining two cases were diagnosed as lymphoblastic lymphomas "type others" according to the Kiel Classification, one with pre-B and the other with transitional pre-B characteristics. The morphologic and immunohistochemical parameters as well as the clinical data from the four cases clearly indicate the heterogeneity of cutaneous non-Hodgkin's lymphomas in children.