Growth/differentiation factor 15 (GDF-15) as new potential serum marker in patients with metastatic colorectal cancer.

BACKGROUND: GDF-15 is a protein belonging to the transforming growth factor beta superfamily that has a role in regulating inflammatory and apoptotic pathways. High level GDF-15 in tumor tissues and plasma correlate with an increased risk of recurrence and reduced overall survival. OBJECTIVE: The aim of this study was to screen GDF-15 capacity to detecting metastatic CRC and compare it with standard tumor markers CEA and CA19-9. METHODS: We collected serum samples from 97 patients with metastatic colorectal cancer and 79 samples from healthy controls. Serum levels of GDF-15, CEA and CA19-9 were measured by immunochemically. A Kaplan-Meier curve was applied for analysis of survival rates, and a log-rank was used for univariate analysis. RESULTS: Serum levels of GDF-15 were significantly higher in patients with colorectal cancer compared to healthy controls (p < 0.001). In addition, serum levels of GDF-15 correlated with extent of liver involvement and patients with higher GDF-15 levels had significantly worse outcome ( p < 0.0001). CONCLUSIONS: Our results show GDF-15 as an effective biomarker in patients with metastatic colorectal cancer with the same sensitivity as CEA. In addition, GDF-15 levels strongly correlate with extension of liver involvement in contrast with CEA.