Th1, Th2, and activated T-cell marker and clinical prognosis in peripheral T-cell lymphoma, unspecified: comparison with AILD, ALCL, lymphoblastic lymphoma, and ATLL.

A new World Health Organization classification was recently proposed. However, classification of peripheral T-cell lymphomas remains to be clarified. Particularly, unspecified type was considered as a heterogeneous category. Here we studied the expressions of chemokine receptors, Th1-associated CXCR3 and CCR5 and Th2-associated marker ST2(L), and activated T-cell receptor OX40/CD134 in 185 patients with nodal T-cell lymphoma, and evaluated the relationship to prognosis. Their expression patterns correlated with the specific subtype of nodal T-cell lymphoma, such as angioimmunoblastic T-cell lymphoma (AILD), anaplastic large cell lymphoma (ALCL), and in peripheral T-cell lymphoma (PTCL), unspecified. In AILD, almost all cases were immunoreactive for OX40/CD134 (96%) and for CXCR3 (89%). In ALCL, all cases were immunonegative for OX40/CD134, and only a few cases (24%) were immunoreactive for CXCR3, whereas almost all cases (94%) were positive for ST2(L). Cases of PTCL, unspecified, were divided into 2 groups; group 1 (cases positive for either ST2(L), CCR5, or CXCR3) tended to show favorable prognosis compared with group 2 (cases negative for ST2(L), CCR5, and CXCR3). Our results indicate that further subtyping of PTCL, unspecified, into groups 1 and 2 could be significant for evaluating prognosis and understanding the functional role of these tumors.