CST4 and neoplasm: Notably, CST4 expression showed no significant associations with established prognostic indicators including tumor invasion depth (T1-T2 vs. T3-T4: 63.03 [38.02-163.44] vs. 53.61 [32.38-90.21] U/mL; P = 0.426), nodal involvement (N+ vs. N0: 52.50 [33.76-88.98] vs. 53.15 [26.08-92.57] U/mL; P = 0.751), or distant metastasis (M1 vs. M0: 57.91 [25.04-98.73] vs. 52.88 [33.96-83.38] U/mL; P = 0.867).