When the clinical features of the 233 HCC cases were stratified according to circRNA expression, hsa_circ_0001020 was found to be significantly associated with serum alpha fetoprotein (AFP) levels (p = 0.003), hsa_circ_0036683 (p = 0.006) and hsa_circ_0001020 (p = 0.004) with tumour size, hsa_circ_0001020 (p = 0.008) with portal vein or hepatic vein invasion, and hsa_circ_0001020 (p = 0.010) with pathological stage (Table 1). Here, AFP is linked to hepatocellular carcinoma.