Diagnostic value of alpha-fetoprotein-L3 and Golgi protein 73 in hepatocellular carcinomas with low AFP levels.

Abstract

This study aimed to investigate the clinical values of serum alpha-fetoprotein-L3 (AFP-L3) and Golgi protein 73 (GP73) in the diagnosis of hepatocellular carcinoma (HCC) with low alpha-fetoprotein (AFP). From January 2011 to December 2013, 50 low-AFP HCC patients confirmed by the color Doppler flow imaging (CDFI) and pathological examinations were collected. Forty-five patients with chronic liver diseases were also selected, including 29 liver cirrhosis patients, 15 chronic hepatitis B patients, and one severe hepatitis patient. Furthermore, 100 health volunteers with no evidence of benign or malignant liver diseases were included. The enzyme-linked immunosorbent assay (ELISA) method was applied to the GP73 quantitative assay. Serum AFP concentrations were determined using immunoassays utilizing enhanced chemiluminescence. Diagnostic accuracy of GP73 and AFP-L3 assays for low-AFP HCC was evaluated using receiver operating characteristic (ROC) curve analysis. Statistical analyses were conducted with the GraphPad Prism 5.0 software. Low-AFP HCC patients (35/50) exhibited higher positive rates of AFP-L3 than non-HCC patients (5/45) and healthy controls (2/100) (both P < 0.05). There were also significant differences in the positive rate of GP73 of low-AFP HCC patients (40/50) compared to those of non-HCC patients (3/45) and healthy controls (1/100) (both P < 0.05). However, no obvious differences in the positive rates of AFP-L3 and GP73 were observed between non-HCC patients and healthy controls (both P > 0.05). ROC curves showed that the area under the curve (AUC) of AFP-L3 for the diagnosis of low-AFP HCC was 0.6994 (sensitivity [Sen] = 70.0%, specificity [Spe] = 95.2%, accuracy = 88.7%), while the AUC of GP73 was 0.8411 (Sen = 80.0%, Spe = 97.2%, accuracy = 92.8%). Compared with single detection, the combination of AFP-L3 and GP73 levels for the diagnosis of low-AFP HCC showed higher Sen (94.0%), Spe (93.1%), and better accuracy (93.3%). Our findings provide empirical evidence that the combination of AFP-L3 and GP73 is a good diagnostic strategy for low-AFP HCC.