Real-world clinical significance of nonbiological factors with staging, prognosis and clinical management in rectal cancer

Background: The clinical guidance of the American Joint Committee on Cancer (AJCC) tumor, node, metastasis (TNM) staging system is established only in biological factors and does not include nonbiological factors (NBFs). We assessed the clinical value of incorporating NBFs into the TNM staging system in point of the clinical management and prognostic prediction accuracy of rectal cancer. Methods: We used the Surveillance, Epidemiology and End Results (SEER) database and identified 12,515 patients with rectal cancer who were diagnosed between 1 January 2011 and 31 December 2015. Multivariate Cox proportional hazards regression analysis and Kaplane-Meier curves were used to determine the probabilities of cancer-specific survival (CSS) according to different TNM-NBF stages. Results: Multivariate Cox regression analysis showed that county percentage with a bachelor's degree, insurance status, unemployment status, and marital status were all significant prognostic NBFs (p < 0.05). The concordance index of TNM-NBF stages was 0.815 (95% confidence interval (CI) 0.8072 -0.8228). Multivariate Cox analyses showed that, compared with NBF0-stage, NBF1-stage was contacted with a 54.5% increased risk of cancer-specific mortality in rectal cancer, which increased to 68.3% in non-metastatic rectal cancer (all p < 0.001). NBF0-stage showed a CSS benefit as compared with NBF1-stage (p < 0.001). Conclusions: We found that NBF-stage was an independent prognostic factor for survival in rectal cancer. The influence of NBFs on survival in rectal cancer warrants greater clinical attention. Furthermore, the consolidation of NBF-stage into the TNM staging system is crucial to better prognostic prediction accuracy and individualized risk-adaptive therapies. (C) 2020 Elsevier Ltd, BASO similar to The Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.