A Subcutaneous Delta-Positive T-Cell Lymphoma That Produces Interferon Gamma

WE report an unusual form of cutaneous T-cell lymphoma characterized by subcutaneous tumors that regress spontaneously, fever, progressive leukopenia, high levels of interferon gamma in the serum, and an increased natural-killer-cell activity of peripheral-blood mononuclear cells. Histologically, the infiltrate consists of nonepidermotropic, pleomorphic lymphoid cells located in the subcutaneous fatty tissue. These cells express the phenotype of immature (CD1+, CD3+, CD4-, CD5-, CD8-), activated (CD30+, CD25+, HLA-DR+) T cells positive for delta T-cell receptors. They express the natural-killer-cell phenotype (CD56+) and produce interferon gamma in cell culture. Case Report A 70-year-old woman presented in March 1985 with recurrent, spontaneously regressing, . . .