AFP and hepatocellular carcinoma: Further analyses indicated that CTC-WBC clusters were associated with larger tumor size (OR = 2.65, 95% CI: 1.58–4.44, P < 0.001) and higher alpha-fetoprotein levels (OR = 2.52, 95% CI: 1.50–4.22, P < 0.001) in hepatocellular carcinoma.