Background and aims Golgi protein 73 (GP73) as a potential serum marker for hepatocellular carcinoma (HCC) has not been validated in large cohort studies. Furthermore, its significance in the assessment of tumour recurrence after HCC resection remains unknown. The aim of this study was to determine the value of serum GP73 in the diagnosis of HCC.

Methods Serum GP73 and alpha-fetoprotein (AFP) were compared in a total of 4217 human subjects in this multicentre study, including 1690 healthy adults, 337 hepatitis B virus (HBV) carriers, 512 patients with cirrhosis, 789 patients with HCC, 61 patients with other malignant liver lesions, 206 patients with benign liver lesions and 622 patients with 14 different kinds of non-liver cancers. The main outcome measures were the specificity and sensitivity of GP73 in patients at risk for the development of HCC.

Results Using 8.5 relative units as a cut-off value, the sensitivity and specificity of serum GP73 for HCC were 74.6% (95% CI 71.5% to 77.6%) and 97.4% (95% CI 96.8 to 98.3%), compared with 58.2% (95% CI 55.2% to 62.1%) and 85.3% (95% CI 83.4% to 88.1%) for AFP (p<0.001) using 35 ng/ml as a cut-off value. The GP73 level was significantly increased in patients with HCC compared with healthy controls (14.7 vs 1.2, p<0.001). Although GP73 levels in HBV carriers (2.9) and patients with cirrhosis (4.7) were somewhat elevated, they were much lower than that in patients with HCC (p<0.001). GP73 decreased following surgical resection of HCC lesions and increased with tumour recurrence. Fourteen types of non-liver cancers were analysed; all the benign and other malignant liver lesions had moderate elevations of GP73, albeit at a much lower level than in HCC.

Conclusions GP73 is an accurate serum marker for the detection of HCC and its recurrence after surgery, with higher sensitivity and specificity than AFP. Clinical implementation of serum GP73 measurement as a standard test for HCC is recommended.