Usefulness of serum des-γ-carboxy prothrombin in detection of hepatocellular carcinoma

AIM: To evaluate whether DCP is better than AFP for differentiating HCC from nonmalignant liver disease and further evaluate the usefulness of DCP in early diagnosis of small HCC. METHODS: Serum DCP and AFP levels were determined in 127 patients. Among these patients, 32 were with non-cirrhotic chronic hepatitis, 34 were with compensated cirrhosis, and 61 were with HCC. The cut-off value for the DCP and AFP were set as 40 mAU/mL and 20 ng/mL, respectively. To compare the diagnostic value of DCP and AFP in distinguishing HCC from nonmalignant chronic liver disease, receiver operating characteristic (ROC) curves were constructed for each assay. RESULTS: The accuracy, sensitivity, and specificity of DCP were higher than AFP in detecting HCC (81.9%, 77%, and 86.4% vs 68.5%, 59%, and 77.3%, respectively). The area under the ROC (AUROC) curves revealed that DCP had a better accuracy than AFP in diagnosis of HCC (0.85 [95%CI, 0.78-0.91] vs 0.73 [95%CI, 0.65-0.81], P = 0.013). In 39 patients with solitary HCC, the positive rates of DCP were 100% in patients with tumor size larger than 3 cm, 66.7% in patients with tumor size 2-3 cm and 50% in patients with tumor size less than 2 cm. The positive rates of AFP in patients with tumor size larger than 3 cm, 2-3 cm and less than 2 cm were 55.6%, 50%, and 33.3%, respectively. The median level of DCP in HCC patients with tumor size larger than 3 cm was significantly higher than those with tumor size 2-3 cm and those with the size of less than 2 cm. CONCLUSION: Our study indicates that DCP has a better diagnostic value than AFP in differentiating HCC from nonmalignant chronic liver disease. DCP has not only a stronger correlation with HCC than AFP in tumor size but also more effectiveness than AFP in detecting small size of HCC.