New data concerning the important role of microenvironment on lymphoma growth are emerging, and in recent years surrogate biomarkers have been identified as prognostic factors for survival in non-Hodgkin lymphoma (NHL). Unlike follicular (FL), diffuse B-cell lymphoma (DLBCL) and Hodgkin lymphoma (HL), there is still no specific internationally accepted risk stratification scoring system for peripheral T-cell lymphomas (PTCL), and the International Prognostic Index (IPI) or the Prognostic Index for T-cell lymphomas (PIT) model are been used to identify higher risk cases of PTCL. Here we retrospectively analyzed the relevance of the well recognized prognostic parameters for T-NHL in 172 patients with different types of PTCL. In 94 cases in whom peripheral blood monocyte count (PBMC) at diagnosis was available, we evaluated whether monocytosis (PBMC >800/mm3) could be used as a simple prognostic factor for overall survival (OS) and outcome in PTCL.
For the entire group with a median follow-up of 19 months (range 1–168 months), the 5-years OS was 42%, and the median OS 48 months. Monocytosis was present in 23% of the evaluable cases and patients with high PBMC (>800/mm3) at diagnosis had a worse OS (median 12 months) compared to those with PBMC < 800/mm3.This difference showed strong statistical significance (p=0.003) (Fig 1) and the Hazard ratio (HR) for PBMC >800/mm3, stratified by histopathological subtype, was 2.81. In particular 3-years OS of patients with PBMC >800/mm3 with anaplastic large cell lymphoma, angioimmunoblastic T-cell lymphoma, and peripheral T-cell lymphoma not otherwise specified was 50%, 25%, and 12%, respectively compared to 86%, 65%, and 50% for those patients with PBMC <800/mm3. In univariate analysis age >60y, advanced stage, bone marrow involvement, ECOG PS >1, LDH>UNL, PBMC >800/mm3, hemoglobin <12 gr/dL, albumin <3.5 gr/L were associated with inferior OS. In multivariate analysis, monocytosis alone retained a negative prognostic value even when adjusted for PIT and stratified by histolopathological subtype (HR 2.41, p=0.015).
In this study, as in others on B-NHL and HL, monocytosis had an independent negative impact on survival in patients with T-NHL. This data, which provide convincing support for the use of monocytosis as a simple prognostic parameter, now need to be further validated in a larger cohort of patients with T-NHL.
No relevant conflicts of interest to declare.
Asterisk with author names denotes non-ASH members.