Plasma Chromogranin A as a Prognostic Marker in Pancreatic Ductal Adenocarcinoma

OBJECTIVES: Neuroendocrine differentiation in pancreatic ductal adenocarcinoma (PDAC) is known, but its clinical significance still remains uncertain. The clinical role of chromogranin A (CgA), a marker of neuroendocrine tumor, was evaluated in patients with PDAC. METHODS: We retrospectively analyzed 350 patients with PDAC. All patients had plasma CgA levels at diagnosis. Patients were classified as normal and high CgA groups according to the upper limit of plasma CgA. RESULTS: There were 202 patients (57.7%) in the normal CgA group and 148 patients (42.3%) in the high CgA group. High CgA group presented higher rate of metastatic disease (61.5% vs 45.0%; P = 0.002) and shorter median overall survival (OS) (8.2 vs 11.6 months; P = 0.015). Upon grouping patients based on clinical stages, OS was significantly different between the CgA groups only in metastatic disease (6.6 vs 7.2 months; P = 0.022). Multivariate analysis showed no association between high CgA and OS (hazard ratio, 1.22; 95% confidence interval, 0.97-1.54; P = 0.090). However, high CgA was associated with poor OS in patients with metastatic disease (hazard ratio, 1.37; 95% confidence interval, 1.01-1.87; P = 0.047). CONCLUSIONS: High CgA levels may predict poor prognosis in patients with pancreatic cancer, especially during metastatic stages.