Abstract
BACKGROUND: Colorectal cancer (CRC) is a common malignancy, especially among older adults. Inflammation has been implicated in cancer progression, making inflammatory indices potential prognostic markers. This study aimed to evaluate the prognostic significance of the Glasgow prognostic score (GPS), neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), lymphocyte/C-reactive protein ratio (LCR), and C-reactive protein/albumin ratio (CAR) in older adults with CRC. METHODS: This population-based, retrospective observational study included patients aged ≥ 65 years with colorectal adenocarcinoma who were admitted to Taichung Veterans General Hospital (Chiayi branch) between 2017 and 2022. Demographic and clinicopathological characteristics, and results of inflammatory indices were collected from medical records for all patients. Receiver operating characteristic (ROC) curve analyses were performed to determine the optimal cutoffs of the inflammatory indices in predicting overall mortality. Associations between the inflammatory indices, overall survival (OS) and progression-free survival (PFS) were determined using univariate and multivariable Cox proportional hazard regression analyses, with model performance evaluated using the C-index. RESULTS: Data of 106 patients were analyzed. After adjusting for confounders, GPS ≥1 (vs 0) significantly predicted poor OS (adjusted hazard ratio [aHR]: 3.80, 95% confidence interval [CI]: 1.30-11.10, p= 0.015, C-index= 0.825) and PFS (aHR: 3.19, 95% CI: 1.34-7.57, p= 0.008, C-index= 0.785). CAR ≥1.0 (vs <1) significantly predicted poor OS (aHR: 2.36, 95% CI: 1.01-5.48), p=0.046, C-index= 0.825) and PFS (aHR: 2.33, 95% CI: 1.14-4.76, p= 0.020, C-index= 0.786). CONCLUSION: Among hospitalized older adults with CRC in Taiwan, high GPS and CAR, but not NLR, PLR or LCR, are potentially useful prognostic indicators for poor OS and PFS.