Nomogram predicting extrahepatic metastasis of hepatocellular carcinoma based on commonly available clinical data

BACKGROUND AND AIM: Extrahepatic metastasis (EHM) of hepatocellular carcinoma (HCC) leads to a worse prognosis. We aimed to develop a nomogram based on noninvasive pretreatment clinical data to predict EHM of HCC sooner. METHODS: Three cohorts containing 1820, 479, and 988 HCC patients were enrolled from three hospitals in different regions in Taiwan and served as the training and validation cohorts. Pretreatment clinical data were analyzed by Cox regression modeling for independent risk factors of EHM. RESULTS: Platelet count ≥ 200 × 10(3)/μL, serum alfa‐fetoprotein ≥ 100 ng/dL, tumor size ≥ 3 cm, tumor number > 1, and macrovascular invasion were independent risk factors for EHM and were used to develop a nomogram. This nomogram had concordance indices of 0.733 (95% confidence interval [CI]: 0.688–0.778) and 0.739 (95% CI: 0.692–0.787) for the prediction of EHM during a 5‐year follow‐up duration in the training and validation cohorts, respectively. A nomogram score > 61 implied a high risk of EHM (hazard ratio [HR] = 3.83; 95% CI: 2.77–5.31, P < 0.001). CONCLUSION: We have developed a nomogram that could accurately predict EHM of HCC and be readily available for formulating individualized treatment for all individual HCC patients to improve therapeutic efficacy.