Reappraisal of nodal Epstein-Barr Virus-negative cytotoxic T-cell lymphoma: Identification of indolent CD5+ diseases

Abstract

Nodal cytotoxic molecule (CM)-positive peripheral T-cell lymphoma (CTL) has recently been recognized as a clinicopathologically distinct disease. To further characterize this disease, here we compared 58 patients with Epstein-Barr virus (EBV)-negative CTL to 48 patients with EBV-positive CTL. The two groups did not differ in histopathology, T-cell receptor (TCR) expression or rearrangement incidences, or survival curves. However, patients with EBV-negative CTL less frequently showed hepatic involvement (P =.007), B symptoms (P =.020), hemophagocytosis (P =.024), and detectable CD4 (P =.002) and CD5 (P =.009). Univariate and multivariate analyses identified three factors that independently predicted favorable survival, onset age <60 years (P =.002), CD5 expression (P =.002), and mixed morphology (P =.013), TCRαβ was not an independent predictor (P =.30), but was strongly linked with long survivorship among patients younger than 60 years old. A prognostic model incorporating these factors worked well for prognostic delineation, independently of the International Prognostic Index (P =.007 vs P =.082) and Prognostic Index for PTCL (P =.020 vs P =.15). Moreover, this constellation of findings indicated two nodal indolent diseases: CD5+TCRαβ (n = 13), and CD5+ NK-cell type lacking TCR expression or clonal TCRγ rearrangement (n = 4). The survival curves for these two groups were significantly superior to others (n = 29, P