HOXD13 and hepatocellular carcinoma: By using an independent case series with wider range of clinical factors, we further assessed whether sPD-1 was detectable at a higher level in plasma from patients with existing HBV-related HCC in comparison with noncases, and whether patients' characteristics in terms of gender, age-of-onset, and clinical variables involved the use of sPD-1 as a biomarker.