Background: Postoperative extrahepatic metastasis (EHM) contributes to a poor prognosis in patients with hepatocellular carcinoma (HCC) after hepatectomy. This study was aimed to develop a practical method that can be used to predict postoperative EHM.
Methods: In total, 578 patients were enrolled. We analyzed the clinicopathological features of the tumors and did a long-term follow-up to observe HCC recurrence. Postoperative EHM was detected in 136 patients, and multivariate analysis was used to confirm independent risk factors for postoperative EHM. After the factors were identified, a predictive scoring system was constructed as a weighted sum of these factors. The cutoff value that determines a high risk for EHM was defined by maximizing the Youden's index of the receiver operating characteristic curve.
Results: Microvascular invasion, incomplete capsule, and larger tumor diameter were the three independent factors predictive for a high risk for EHM. The scoring system was derived with an area under the curve (AUC) of 0.81 for postoperative 10-year EHM prediction. A cutoff value of 43 was derived and validated with a sensitivity >90% and specificity >60% to predict the development of EHM. This system was further verified in a subgroup of Barcelona Clinic Liver Cancer stage 0-A patients with an AUC of 0.82. When the cutoff value was set at 43, the sensitivity and specificity were 90.38% and 64.88%, respectively.
Conclusions: Our predictive scoring system may be used to identify HCC patients who have a high risk for EHM following curative hepatectomy.