We found that plasma circ-CYP24A1 (Figures 4C–F), circ-ALDH3A2 (Figures 4G–J) and circ-DNA2 (Figures 4K–N) levels displayed correlations to maximum tumor diameter, tumor thickness, preoperative serum SCC-Ag and serum SCC-Ag 1 month after surgery. Here, CYP24A1 is linked to neoplasm.