The prognostic value of circulating plasma DNA level and its allelic imbalance on chromosome 8p in patients with hepatocellular carcinoma

Abstract

We demonstrated that chromosome 8p deletion is associated with metastasis of human hepatocellular carcinoma (HCC). This study assesses the value of circulating plasma DNA level and its allelic imbalance (AI) on chromosome 8p in the prediction of HCC prognosis. Blood samples were collected from 79 patients with HCC before operation, 20 patients with liver cirrhosis, and 20 healthy volunteers. The HCC and adjacent non-tumor liver tissues were obtained from surgical specimens. Plasma DNA was extracted and quantified. Two microsatellite markers on chromosome 8p, D8S258 and D8S264, were selected and used in the AI analysis. The circulating plasma DNA level was found to closely associate with tumor size (P=0.008) and TNM stage (P=0.040), negatively associate with the 3-year disease-free survival (DFS) (P=0.017) and overall survival (OS) (P=0.001). AI at D8S258 in plasma DNA was significantly correlated with tumor differentiation (P=0.050), TNM stage (P=0.010), and vascular invasion (P=0.023), negatively correlated with the 3-year DFS (P=0.005) and OS (P=0.036). However, AI at D8S264 was only closely associated with 3-year DFS (P=0.014). Combined detection of AI at D8S258 and circulating plasma DNA level was independently associated with DFS (P=0.018) and OS (P=0.002) of patients with HCC. For patients with both AI at D8S258 and a higher level of plasma DNA, the 3-year DFS and 3-year OS rates were decreased remarkably (P=0.014 and 0.044). Combination of circulating plasma DNA level and AI at D8S258 might be an independent predictor for prognosis of HCC patients.