Primary tumour and lymph node radiomics assessment in PET-CT in non-metastatic nasopharyngeal carcinoma patients

Abstract

Purpose: To evaluate the prognostic value of radiomic features extracted from pre-treatment PET-CT images of the primary tumours (PT) and lymph nodes (LNs) in locally advanced nasopharyngeal carcinoma (NPC) patients. Methods and materials: A total of 145 consecutive patients (median age 48 years, 75.2% male) with newly diagnosed NPC were included. Radiomics analysis was performed on 118 PT and 66 LN images. Conventional PET parameters (SUVmax, SUVmean, and TLG), shape-based features, and 6 robust texture features were extracted. This data was used to analyse the correlation with 3-year overall survival (OS) and progression-free survival (PRFS) based on a Kaplan-Meier log-rank test. Results: One PET radiomics feature (LN sphericity) was significantly predictive of OS (p=0.024) and PRFS (p=0.002). Independent CT predictive radiomic features were PT GLRM LRE (p=0.011), LN sphericity (p=0.011), and compactness (p=0.042) for OS, and PT GLRM LRE (p = 0.039) and LN sphericity (p = 0.008) for PRFS. Conclusion: CT shape-based features and texture features extracted from primary tumours and LNs provide significant predictive value for survival in patients with NPC. LN PET radiomics information was significantly predictive for survival and performed better than primary features. The unity of LN radiomics can be further validated by prospective randomised trials, considering their potential in predicting clinical outcomes of tumour patients.