New insights into peripheral T-cell lymphomas.

Peripheral T-cell lymphomas comprise a morphologically diverse group of malignant lymphoproliferative disorders that arise from postthymic T cells. Currently, there exists no universally accepted system of classification of peripheral T-cell lymphoma. Recent efforts to elucidate pathogenetic mechanisms and define recognizable entities have begun to clarify the nature of these tumors. These and future studies may one day lead to a unified system of classification of peripheral T-cell lymphoma that is reproducible, biologically relevant, and more predictive of clinical behavior and prognosis.