High serum serotonin as a favorable prognostic factor for patients with hepatocellular carcinoma

Abstract BackgroundSerotonin contributes to liver cancer progression; however, it also plays a pivotal role in liver regeneration after partial resection. This study aims to elucidate whether high serum serotonin is a prognostic factor for patients with hepatocellular carcinoma (HCC).MethodsWe measured the pre-operation serum serotonin level of patients with HCC. Based on the median value of serum serotonin, patients were divided into the high serotonin group and the low serotonin group. The survival rates after operation were compared between the two groups.ResultsThe median serum serotonin level for 176 patients was 90.5 ng/mL (range, 1.0 − 399.5); 88 patients with serum serotonin level ≥ 90.5 were allocated to the high serotonin group and 88 patients to the low serotonin group. Histological findings showed that tumor stage was not different between the two groups. After a median follow-up period of 3.2 years (range, 0.9 − 7.4), median overall survival was 6.6 years (95% confidence interval [CI], 5.7–NA) and 5.7 years (95% CI, 3.5–NA) in the high and the low serotonin groups, respectively (P = 0.042). The median recurrence-free survival of patients in the high serotonin group (2.2 years [95% CI, 1.7–3.2]) tended to be longer than that of patients in the low serotonin group (2.0 years [1.0–2.2]) (P = 0.091). The independent variables for overall survival were the high serum serotonin level (P = 0.049) and des-gamma-carboxy prothrombin level (P = 0.032).ConclusionsHigh serum serotonin could be a favorable prognostic factor for HCC patients undergoing liver resection.Trial registrationThe study was approved (protocol number: 131) by the institutional review boards of Nihon University on December 15 in 2011.