Degree of CD25 Expression in T-Cell Lymphoma Is Dependent on Tissue Site

Fig. 2.

Modulation of CD25 and cutaneous lymphocyte antigen (CLA) expression in human T-cell lymphotropic virus I-positive adult T-cell lym-phoma/leukemia. A, adult T-celllymphoma/leukemia in skin shows a perivascular and epidermotropic infiltrate of tumor cells. B, CD25 is strongly expressed in 100% of tumor cells in skin. C, tumor cells in skin show variable strong reactivity for CLA. D, an enlarged lymph node biopsied 1 day later shows an interfollicular infiltration of tumor cells surrounding and encroaching on a germinal center (GC). E, CD25 is strongly expressed only in sinusoidal tumor and is expressed weakly in the subcapsular location, consistent with progressive antigen loss upon migration into the nodal parenchyma. F, CLA is strongly positive only in tumor cells within the subcapsular sinuses. G, higher magnification of indicated areas in (E) shows pleomorphic cerebriform tumor cells identical to those in skin. H, higher magnification of F shows CD25+ intrasinusoidal tumor cells adjacent to CD25-negative tumor cells within lymph node. I, higher magnification of F shows CLA-negative tumor in deep paracortex admixed with CLA+ high endothelial venules.