The Value of Insulin-like Growth Factor in Urinary Exosomes of Bladder Urothelial Carcinoma

Objective To investigate the diagnostic value of insulin-like growth factor 2 (IGF2) in urine exosomes for bladder urothelial carcinoma. Methods The patients with bladder urothelial cancer admitted in Peking Union Medical College Hospital from September to December 2020 were selected as the research objects, and the patients with non-malignant urinary system disease cancers admitted in the same period were selected as the control group. Fluorescent RT-PCR was used to detect the level of IGF2 in urine exosomes. The pathological results of cystoscopy or transurethral bladder tumor resection were regards as the gold standard, and the sensitivity, specificity, positive likelihood ratio and negative likelihood ratio of the diagnosis of bladder cancer were calculated based on the expression level of IGF2 in urine exosomes. Results There were 35 cases in the urothelial cancer group, with an average age of (65.43±12.22) years, and there were 60 cases in the non-urothelial cancer group, with an average age of (51.68±13.07) years. The sensitivity of urinary exosomes IGF2 in diagnosing bladder urothelial carcinoma is 71.4% (95% CI: 53.5%-84.8%), specificity is 90% (95% CI: 78.8%-95.9%), and the positive likelihood ratio is 7.14 (95%CI: 3.25-15.7), the negative likelihood ratio was 0.32 (95%CI: 0.19-0.54). Conclusions The content of IGF2 in urine exosomes is promising as a preliminary screening index for bladder cancer.