Real‐World clinical features and survival outcomes associated with primary gastrointestinal natural killer/T‐cell lymphoma from 1999 to 2020

BACKGROUND: Primary gastrointestinal natural killer (NK)/T‐cell lymphoma (PGINKTL) is a rare T‐/NK‐cell lymphoma subtype, and the clinical features and survival outcomes remain largely unknown. METHODS: To summarize the clinical features and survival outcomes of PGINKTL, PGINKTL cases diagnosed at our hospital from May 1999 to December 2020 were reviewed; and the clinical data, information on treatment strategies, and survival were collected. Survival analysis was performed using the Kaplan–Meier method and multivariable Cox proportional hazards regression. We constructed a nomogram to visualize the survival prediction of PGINKTL. The discriminative ability and calibration of the nomogram for prediction were tested using the concordance index (C‐index) and calibration plots. RESULTS: The cohort included 81 cases, the median age was 36 years (range, 7–80 years), and the male‐to‐female ratio was 1.7:1. The most common clinical symptom at the time of diagnosis was abdominal pain (71.6%). The most common lesion site was the colon (59.3%). During a median follow‐up period of 37.7 months, the median overall survival (OS) time of 81 patients was 4.0 months (95% confidence interval [CI], 3.1–4.9 months), and the 2‐year OS rate was 30.7% (95% CI, 20.3%–40.1%). The multivariate analyses indicated that patients with an Eastern Cooperative Oncology Group (ECOG) performance status (PS) score ≥2, serum lactic dehydrogenase (LDH) level ≥ the upper limit normal (ULN), and perforation had worse OS. We used these data to establish a nomogram to predict survival for PGINKTL. The nomogram displayed good accuracy, with a C‐index of 0.726. CONCLUSION: The clinical features and poor outcomes of PGINKTL, which is a rare and fatal lymphoma type, are presented. The proposed nomogram provides an individualized estimate of survival for these patients. In the future, the study focused on exploring a better treatment strategy to improve survival is required in PGINKTL.