Textural analysis in FDG PET of locally advanced non-small cell lung cancer: Prognostic value of entropy

Introduction. - In the current context of personalized medicine, textural analysis promises to be an accurate approach of cancer prognosis. The lack of standardization and the multitude of textural indices limited radiomics studies reproducibility as an obstacle of introduction of textual analysis into clinical practice. Our study assessed the prognostic value of entropy in ¹⁸F-FDG PET/CT in locally advanced non-small cell lung cancer (NSCLC). Method. - Patients who performed ¹⁸F-FDG PET/CT for lung cancer staging between September 2015 and April 2017 in 2 hospitals were included for conventional and textural PET parameters extraction. A retrospective analysis of patient was performed over 24 months to determine the progression-free survival and overall survival. Results. - Forty-two patients were included. Progression-free survival was significantly correlated with entropy on multivariate regression (cut-off at 8.4) with a hazard ratio of 3.04 (95 % CI 1.13-8.16) (P = 0.03), as MTV (P < 0.001). Neither conventional PET parameters nor entropy was a significant association with overall survival. Conclusion. - These results confirmed the external validity and robustness of FDG PET entropy as an independent prognostic factor of progression-free survival in patients with locally advanced NSCLC, in addition to Conventional PET. (authors)