Significance of serum ferritin as a prognostic factor in advanced hepatobilia cancer patients treated with Korean medicine: a retrospective cohort study

Background: Advanced hepatobiliary cancers are highly lethal cancers that require precise prediction in clinical practice. Serum ferritin level increases in malignancy and high serum ferritin level is associated with poor survival in various cancers. This study aimed to identify whether serum ferritin could independently predict the overall survival (OS) of patients with advanced hepatobiliary cancers. Methods: The retrospective cohort study was performed by reviewing medical records of patients with advanced hepatobiliary cancers from June 2006 to September 2016. The demographic and clinicopathological characteristics as well as the biochemical markers were evaluated at the initiation of Korean medicine (KM) treatment. The OS was calculated using Kaplan-Meier estimates. The Cox proportional hazard model was used to identify the independent prognostic significance of serum ferritin for survival. Results: The median OS of all subjects was 5.1 months (range, 0.5-114.9 months). The median OS of group with low ferritin levels and that with high ferritin levels was 7.5 months (range, 0.7-114.9 months) and 2.8 months (range, 0.5-22.8 months), respectively (P < 0.001). The results of the univariate analysis showed that the Eastern Cooperative Oncology Group Performance Status (ECOG-PS) (P = 0.002), tumor type (P = 0.001), prior treatment (P = 0.023), serum ferritin (P < 0.001), hemoglobin (P = 0.002), total bilirubin (P = 0.002), gamma-glutamyl transpeptidase (P = 0.007), albumin (P = 0.013), white blood cell (P = 0.002), and C-reactive protein (CRP) (P < 0.001) were significant factors for the patients' survival outcome. On multivariate analysis controlling confounding factors, ferritin (P = 0.041), CRP (P = 0.010), ECOG-PS (P = 0.010), and tumor type (P = 0.018) were identified as independent prognostic factors for survival. Conclusions: These results indicate that serum ferritin is a valid clinical biochemical marker to predict survival of patients with advanced hepatobiliary cancers.