Univariate Cox regression analysis showed that the lower levels of p21 protein expression in the tumor were a strong predictor of OS survival (HR: 0.473; 95% confidence interval: 0.236‐0.950; P = .035) and DFS (HR: 0.423; 95% confidence interval: 0.241‐0.741; P = .003). Here, CDKN1A is linked to neoplasm.