OBJECTIVETo compare the predictive values of eight staging systems for primary liver cancer in the prognosis of combined hepatocellular-cholangiocellular carcinoma (cHCC-CC) patients after surgery.

METHODSThe clinical data of 54 cHCC-CC patients who underwent hepatectomy or liver transplantation from May 2005 to Augest 2013 in Chinese PLA General Hospital were collected. We evaluated the prognostic value of the Okuda staging system, Cancer of the Liver Italian Program (CLIP) score, French staging system, Barcelona Clinic Liver Cancer (BCLC) staging system, 7th edition of tumour-node-metastasis (TNM) staging system for hepatocellular carcinoma and intrahepatic cholangiocarcinoma (ICC), Japan Integrated Staging (JIS) score, and Chinese University Prognostic Index. The distribution, Kaplan-Meier method, Log-rank test, and area under a receiver operating characteristic curve were used to compare the prognosis-predicting ability of these different staging systems in 54 cHCC-CC patients after surgery.

RESULTSThe TNM staging system for ICC and JIS score had a better distribution of cases. The 12-and 24-month survivals of the entire cohort were 65.5% and 56.3%, respectively. A Log-rank test showed that there was a significant difference existing in the cumulative survival rates of different stage patients when using TNM staging system for ICC (stage 1 vs. stage 2, P=0.012; stage 2 vs. stage 3-4, P=0.002), Okuda staging system (stage 1 vs. stage 2, P=0.025), and French staging system (stage A and stage B, P=0.045). The 12-and 24-month area under curve of TNM staging system for ICC, BCLC staging system, JIS score, and CLIP score were 0.836 and 0.847, 0.744 and 0.780, 0.723 and 0.764, and 0.710 and 0.786, respectively.

CONCLUSIONThe 7th edition of TNM staging system for ICC has superior prognostic value to other seven staging systems in cHCC-CC patients undergoing surgical treatment.