B2M and cervical squamous intraepithelial neoplasia: Median serum levels for 24 h cystatin C (p < 0.01) and 48 h β2M levels (p < 0.001) and baseline urine NGAL (p=0.02) were higher in CIN patients compared to controls with AUROCs of 0.75, 0.78, and 0.74, respectively, for the early diagnosis of CIN.