Clinical correlation between serum YKL-40 protein level and recurrence of non-muscle invasive bladder cancer

Bladder cancer is one of the most common malignant tumors of the urinary system. In particular, the non-muscle invasive bladder cancer (NMIBC) accounts for 70% of newly diagnosed bladder tumors, among which the stage Ta accounts for about 70%, T1 20%, and Tis 10% (1). The preferred treatment for NMIBC is transurethral resection of bladder tumor (TURBT); however, it has been reported that tumor recurrence occurs in up to 50-70% of patients within 2 years after surgery (2). The high post-operative recurrence rate of NMIBC remains a challenging issue in the clinical settings