Development and validation of a nomogram comprising GLUT1 and clinical characteristics for predicting overall survival in intrahepatic cholangiocarcinoma.

BACKGROUND: Intrahepatic cholangiocarcinoma (iCCA) is a highly aggressive malignancy arising from the intrahepatic bile duct epithelium, with increasing global incidence and poor prognosis due to late diagnosis and limited therapeutic options. Current prognostic models such as tumor-node-metastasis (TNM) staging exhibit suboptimal accuracy and lack integration of molecular biomarkers. Our study aims to explore the prognostic significance of SLC2A1 (encoding GLUT1) in iCCA and develop a predictive nomogram integrating clinical features. METHODS: We analyzed SLC2A1 (encoding GLUT1) mRNA expression in various solid tumors using The Cancer Genome Atlas (TCGA) data. Immunohistochemistry (IHC) was performed to assess GLUT1 protein expression in 95 postoperative iCCA patients (median follow-up: 32 months). A nomogram integrating age, tumor size, and GLUT1 was developed to predict 2- and 3-year overall survival (OS) using Cox regression and internally validated via 500× bootstrap resampling. Performance was evaluated by time-dependent receiver operating characteristic (ROC) curves [area under the curve (AUC)] and decision curve analysis (DCA). RESULTS: TCGA data showed significant upregulation of SLC2A1 mRNA in multiple solid tumors versus adjacent normal tissues. In iCCA patients, GLUT1 protein expression was markedly higher in tumor tissues than in adjacent non-tumor tissues. High GLUT1 expression was significantly associated with vascular invasion, advanced tumor (T)/node (N)/TNM stages, and poorer OS. The nomogram demonstrated excellent discriminatory ability, with AUC values of 0.74 (2-year OS) and 0.77 (3-year OS), outperforming TNM staging (AUC: 0.69 for 2-year OS and 0.67 for 3-year OS). CONCLUSIONS: Our study establishes GLUT1 as an independent prognostic biomarker and provides a clinically applicable tool for individualized risk stratification. While our nomogram shows promise for guiding postoperative management, its single-center design warrants external validation in future multi-center studies.