Objectives: Neuroendocrine tumor originates from several sites. This study was conducted to reveal the differences in clinical course of neuroendocrine tumors by the origin.
Methods: We reviewed data of patients diagnosed with neuroendocrine tumor between January 1996 and July 2007.
Results: A total of 371 patients were enrolled [pancreas 60, gastrointestinal (GI) tract 210, lung 35, other sites 46, unknown primary sites 20]. The primary tumor site correlated with the stage (P=0.000) and grade (P=0.000). At diagnosis, metastasis was observed in 28.3%, 6.7%, and 2.9% of the cases in pancreatic, GI, and pulmonary neuroendocrine tumors, respectively. Grade 3 neuroendocrine tumor was observed in 7.7%, 0.5%, and 0.0% in pancreatic, GI, and pulmonary neuroendocrine tumors. Overall survival was 116.0 months (95% confidence interval, 86.9-145.1). Overall survival was 116.0 months in pancreatic neuroendocrine tumor, not reached in GI neuroendocrine tumor and 120.0 months in pulmonary neuroendocrine tumor (P=0.024). The recurrence rate was 18.0%. It was 20.9%, 11.9%, and 2.9% in pancreatic, GI, and pulmonary neuroendocrine tumors (P=0.062). In multivariate analysis, stage, grade, and age were prognostic for overall survival (OS). Stage, grade, and sex were prognostic for disease-free survival.
Conclusions: Neuroendocrine tumors from the pancreas, GI tract, and lung showed different clinical characteristics.