High truncated-O-glycan score predicts adverse clinical outcome in patients with localized clear-cell renal cell carcinoma after surgery

Truncated O-glycans, including Tn-antigen, sTn-antigen, T-antigen, sT-antigen, are incomplete glycosylated structures and their expression occur frequently in tumor tissue. The study aims to evaluate the abundance of each truncated O-glycans and its clinical significance in postoperative patients with localized clear-cell renal cell carcinoma (ccRCC). We used immunohistochemical testing to analyze the expression of truncated O-glycans in tumor specimens from 401 patients with localized ccRCC. Truncated-O-glycan score was built by integrating the expression level of Tn-, sTn- and sT-antigen. Kaplan-Meier survival and Cox regression analysis were done to compare clinical outcomes in subgroups. Receiver operating characteristic (ROC) was applied to assess the impact of prognostic factors on overall survival (OS) and recurrence-free survival (RFS). The results identified Tn-, sTn-, sT-antigen as independent prognosticators. The OS and RFS were shortened among the 198 (49.4%) patients with high Truncated-O-glycan score than among the 203 (50.6%) patients with low score (hazard ratio for OS, 7.060; 95% confidence interval [CI]: 2.765 to 18.027; p <0.001; for RFS, 4.612; 95% CI: 2.141 to 9.931; p <0.001). There is no difference between low-risk patients and high-risk patients in low score group (p = 0.987). High-risk patients with low score showed a better prognosis than low-risk patient with high score (p = 0.029). The Truncated-O-glycan score showed better prognostic value for OS (AUC: 0.739, p = 0.003) and RFS (AUC: 0.719, p = 0.003) than TNM stage. In summary, the high Truncated-O-glycan score could predict adverse clinical outcome in localized ccRCC patients after surgery.