Elevated Preoperative Serum CA125 Predicts Larger Tumor Diameter in Patients with Hepatocellular Carcinoma and Low AFP Levels

AIM: Little is known about the association between cancer antigen 125 (MUC16/CA125) concentrations and tumor diameter of patients with hepatocellular carcinoma (HCC) and low AFP levels. To fill this gap in our knowledge, we conducted a retrospective study of 427 patients with HCC with AFP ≤200 ng/mL who underwent R0 resection at our center. METHODS: The associations between CA125 concentrations and patients' clinicopathological characteristics were analyzed. Survival vs CA125 levels was also evaluated between patient groups with CA125 ≤30 U/mL or CA125 >30 U/mL. Independent risk factors of disease-free survival (DFS) and overall survival (OS) were analyzed with Cox hazard regression model. RESULTS: Elevated preoperative serum CA125 was significantly associated with maximal tumor diameter (MTD) >5 cm and female sex (P < 0.001 and P=0.044, respectively). The DFS and OS of patients with CA125 ≤30 U/mL (n = 392) were significantly higher compared with those with CA125 >30 U/mL (n = 35) (P=0.003 and P=0.001 respectively). Multivariate analysis revealed that MTD >5 cm was an independent risk factor of DFS (HR = 1.891, 95% CI: 1.379–2.592, P < 0.001) and OS (2.709, 1.848–3.972, P < 0.001). CONCLUSIONS: In conclusion, elevated preoperative serum CA125 predicted larger tumor diameter and poor prognosis after patients with HCC with AFP ≤200 ng/mL underwent R0 resection, which may be explained by the elevation of the preoperative serum CA125 level significantly associated with MTD>5 cm.