Nomograms for pre- and postoperative prediction of long-term survival for patients who underwent hepatectomy for multiple hepatocellular carcinomas

Abstract

Objective: To develop prognostic nomograms for patients undergoing hepatectomy for multiple hepatocellular carcinomas (mHCCs). Background: The prognostic prediction after hepatectomy for mHCCs has not been well established. Methods: A training cohort (n = 540) was analyzed to construct two nomograms based separately on data obtained before and after hepatectomy for mHCCs at the Eastern Hepatobiliary Surgery Hospital (EHBH) between 2000 and 2006. The internal and external validations were performed in two independent cohorts (n = 180 each) collected from the EHBH between 2007 and 2010 and the Sun Yat-Sen University between 2000 and 2007. The predictive accuracy was measured by concordance index (C-index) and calibration curve. Results: Serum AFP level, HBV-DNA load, MELD score, tumor number, total tumor diameter and the ratio of largest to smallest tumor diameter were incorporated into the preoperative nomogram for overall survival (OS) prediction. In addition to these variables, microvascular invasion, tumor capsule, type of hepatectomy and local invasion/metastasis were incorporated into the postoperative nomogram. All calibration curves for probability of OS fitted well. In the training cohort, the preoperative nomogram achieved a C-index of 0.75 (95% CI, 0.72–0.78) in predicting OS, and accurately stratified patients into 4 prognostic subgroups (5-year OS rates: 65.9%, 46.3%, 29.6%, and 4.1%, p<0.001). The postoperative nomogram had a C-index of 0.80 which was higher than those of the 4 conventional staging systems (0.53–0.62). These results were supported by the internal and external validations. Conclusions: The two nomograms showed accurate pre- and postoperative prediction of post-hepatectomy prognosis in patients with mHCCs.