Elevated serum levels of bone sialoprotein (BSP) predict long-term mortality in patients with pancreatic adenocarcinoma

Patients with pancreatic adenocarcinoma (PDAC) still face a very limited prognosis. At early stage, surgical tumor resection might offer long-term survival but disease recurrence is common and the existing stratification algorithms are often unsuitable to identify patients who particularly benefit from surgery. Here, we investigated the potential role of bone sialoprotein (BSP) as a circulating marker in patients undergoing resection of PDAC. We used ELISA to determine serum concentrations of BSP in a cohort of 132 PDAC patients as well as 39 healthy controls. Circulating BSP levels were significantly higher in PDAC patients compared to healthy controls. Notably, elevated preoperative BSP levels above the ideal cut-off value of 4743 pg/ml turned out as a significant predictor for an impaired postoperative survival. The potential of preoperative BSP levels as a prognostic marker was further underlined by uni- and multivariate Cox-regression analyses including various tumour- and patient-specific. Finally, high tumoral BSP expression was also associated with a significantly impaired long-term survival. In conclusion, we identified a novel role of circulating BSP as a biomarker in PDAC patients undergoing tumor resection. Such data might help to establish new preoperative stratification strategies to better identify patients who particularly benefit from tumor resection.