A New and Validated Clinical Prognostic Model (EPI) for Enteropathy-Associated T-cell Lymphoma.

PURPOSE Enteropathy-associated T-cell lymphoma (EATL) is a rare intestinal non-Hodgkin lymphoma with a poor, though variable prognosis. The International Prognostic Index (IPI) and the prognostic index for peripheral T-cell lymphoma (PIT) have limited predictive value for outcome of EATL. The purpose of this study was to develop and validate a prognostic model for EATL, which can identify high-risk patients who need more aggressive therapy. EXPERIMENTAL DESIGN This retrospective multicenter study was based on 92 patients and included 45 patients diagnosed with EATL between 1999 and 2009 from the Netherlands and 47 patients from England and Scotland, diagnosed with EATL between 1994 and 1998. A new EATL prognostic index (EPI) was constructed using the RPART (recursive partitioning and regression trees) procedure. Validation was performed applying the bootstrap method. RESULTS Three risk groups were distinguished (P < 0.0001): a high-risk group, characterized by the presence of B-symptoms [median overall survival (OS) of 2 months]; an intermediate-risk group, comprising patients without B-symptoms and an IPI score ≥ 2 (7 months); and a low-risk group, representing patients without B-symptoms and an IPI score of 0 to 1 (34 months). Internal validation showed stability of statistical significance and prognostic discrimination. In contrast with the IPI and PIT, the EPI better classified patients in risk groups according to their clinical outcome. CONCLUSIONS Our new, validated, prognostic model EPI accurately predicts survival outcome in EATL and may be used for patient selection for new therapeutic strategies and evaluation of clinical trials.