Factors predicting survival in peripheral T‐cell lymphoma in the USA : a population‐based analysis of 8802 patients in the modern era

Summary Current prognostic models for peripheral T‐cell lymphoma ( PTCL ) have multiple limitations, and questions exist regarding applicability to current patients. We utilized the Surveillance Epidemiology and End Results ( SEER )‐18 database to evaluate factors affecting overall survival ( OS ) of PTCL in the modern era and identified 8802 patients between 2000–2010. Most subtypes of PTCL increased in incidence during the study period. In univariate analyses, age >55 years, black race, advanced stage, absence of extra‐nodal disease, omission of radiation therapy ( RT ) and high‐risk histology each predicted inferior OS ( P  < 0·0001). Multivariate analysis ( MVA ) demonstrated that hepatosplenic, enteropathy‐associated and extra‐nodal Natural Killer/T cell histologies, each had hazard ratios >1·5 ( P  ≤ 0·0001) for death. Further, age ≥55 years, black race and advanced stage maintained their significance in the MVA ( P  < 0·0001 each). Based on the significant factors, a prognostic model was constructed and subsequently validated in an independent cohort. The new model incorporated age, stage, histology and race, with an OS ranging from 9 months (highest risk group) to 120 months (lowest risk group). In summary, this is the largest study of PTCL patients in the modern era that provides risk stratification utilizing a new prognostic model that can be incorporated into future prospective clinical trials.