No significant association was found between Id-1 expression and the other clinico-pathological characteristics including age, gender, hepatitis B virus (HBV) surface antigen (HBsAg) status, cirrhosis, serum alpha-fetoprotein (AFP) and alanine aminotransferase (ALT) levels, tumor dimension, tumor number, vascular invasion, or tumor encapsulation (Supplementary Table 1). The gene discussed is AFP; the disease is neoplasm.