The aim of this study was to assess the usefulness of neuron-specific enolase (NSE) concentrations as a prognostic factor in patients with neuroendocrine neoplasms and to determine the relationship between NSE and clinicopathological features. Serum NSE levels were measured in 179 NEN patients before treatment. It was found that NSE levels in patients with a primary pancreatic location were higher compared to patients with a small intestine lesion (P = 0.015). NSE levels were significantly higher in patients with primary pancreatic location with histological grade G2 compared with the group with low-grade G1 (P = 0.047). Patients with initial liver involvement showed significantly higher NSE levels compared to patients with tumour location in the pancreas (P = 0.009). Statistical analysis confirmed that higher NSE levels were associated with disease progression (P = 0.001) in both the overall study group and in patients with tumours in the pancreas and small intestine. During treatment monitoring, an increase in median NSE concentrations was observed in patients with persistent progression with subsequent blood draws, and a decrease in NSE concentrations was observed in patients with disease stabilisation. We showed that NSE concentrations have prognostic value for progression-free survival in addition to primary liver involvement. In conclusion, the most important results of the study include the demonstration of an association between NSE concentrations and clinical status, which confirms its usefulness in patient monitoring and as a potential predictive indicator for progression-free survival in patients with NENs.
Keywords: neuroendocrine neoplasms; neuron-specific enolase; pancreas; prognostic factor; small intestine.