A Nomogram in Predicting Risks of Intrahepatic Cholangiocarcinoma After Partial Hepatectomy for Hepatolithiasis

Background Hepatolithiasis is associated with the development of intrahepatic cholangiocarcinoma (ICC). This study sought to investigate risk factors of ICC for hepatolithiasis after partial hepatectomy (PH) and to develop a model for predicting ICC risk. Methods Data on consecutive patients who underwent PH for hepatolithiasis at the Eastern Hepatobiliary Surgery Hospital between January 2009 and December 2011 were reviewed. Independent risk factors of ICC identified by Cox regression model were used to develop a nomogram in predicting ICC after PH for hepatolithiasis. Results Of 2056 patients, 168 developed ICC at a median follow-up of 7.2 years. The cumulative incidences of ICC at 3, 5, and 8 years after PH for hepatolithiasis were 3.0%, 6.5%, and 12.9%, respectively. Independent risk factors of ICC were identified to be a long duration of hepatolithiasis-related symptoms (hazard ratio, 1.088 [95% confidence interval, 1.057–1.120]), metabolic syndrome (2.036 [1.210–3.425]), a high neutrophil-to-lymphocyte ratio (1.250 [1.009–2.816] for 3–5 vs ≤3; 1.538 [1.048–2.069] for ≥5 vs ≤3), hepatic atrophy (1.711 [1.189–2.462]), segmental intensity differences (1.513 [1.052–2.176]), persistent biliary strictures (2.825 [1.480–5.391]), and residual stone disease (2.293 [1.511–3.481]). By incorporating these factors, a constructed nomogram showed a concordance index of 0.721 to predict ICC. The calibration plots demonstrated good agreement between observed and predicted morbidities. The optimal cutoff point for the nomogram was 48 in differentiating between high and low-risk of ICC. Conclusions A nomogram for predicting ICC after PH for hepatolithiasis was constructed based on risk factors of developing ICC. Patients with a nomogram point of ≥48 were predicted to have a high risk of ICC.