Prognostic Nomogram for Overall Survival in Extranodal Natural Killer/T-Cell Lymphoma Patients

Patients with extranodal natural killer/T-cell lymphoma (ENKTL) have remarkably different outcomes, and no prognostic model has gained widespread acceptance until now. We retrospectively analyzed 81 previously untreated ENKTL patients and constructed a prognostic nomogram to estimate overall survival (OS) based on the Cox proportional hazards model. The calibration curve showed that the nomogram was able to predict OS accurately. Background: Extranodal natural killer/T-cell lymphoma (ENKTL) is a rare lymphoid malignancy with diverse clinical features and prognoses. The aims of this study were to explore the pretreatment prognostic factors of ENKTL and develop a new individual prognostic model. Patients and Methods: We retrospectively enrolled 81 ENKTL patients with newly diagnosed disease between June 2006 and August 2017 at the Affiliated Cancer Hospital of Guangxi Medical University. Survival analysis was used to assess the prognostic value of various factors. A nomogram was developed to predict overall survival (OS) based on the Cox proportional hazards model. Results: The median survival time of the patients was 48 months, and the 5-year OS rate was 47.5%. Cox regression analysis showed that the prognostic factors of OS for ENKTL patients included Eastern Cooperative Oncology Group performance status, Ann Arbor stage, pretreatment albumin-to-globulin ratio, and platelet count. A prognostic nomogram was developed to predict the OS rate for ENKTL patients based on these factors. The calibration curve showed that the nomogram was able to predict OS accurately. The concordance index of the nomogram for OS prediction was 0.807. Conclusion: Our proposed nomogram based on Eastern Cooperative Oncology Group performance status, Ann Arbor stage, albumin-to-globulin ratio, and platelet count provides an individualized risk estimate of OS in patients with ENKTL. (C) 2018 The Authors. Published by Elsevier Inc.