Evaluation of the World Health Organization 2010 Grading System in Surgical Outcome and Prognosis of Pancreatic Neuroendocrine Tumors

Objective: The objective of this study was to evaluate the clinical consistency of the new World Health Organization 2010 grading and the European Neuroendocrine Tumor Society 2006 TNM staging systems on the surgical outcome for patients with pancreatic neuroendocrine tumors (p-NETs). Moreover, we will discuss their prognostic value. Methods: The medical records of 110 consecutive patients with p-NETs who were surgically treated in our center from January 2002 to December 2012 were reviewed. Results: Sixty-five patients were diagnosed as having neuroendocrine tumor G1, 27 patients had neuroendocrine tumor G2, 14 patients had neuroendocrine carcinoma G3, and 4 patients had mixed adenoneuroendocrine carcinoma; the survival rates at 5 years were 82.6%, 52.7%, 25.7%, and 0%, respectively (P < 0.001). The TNM stage was I in 48 patients, II in 39 patients, III in 11 patients, and IV in 12 patients; the 5-year survival rates were 83.1%, 72.1%, 0%, and 0%, respectively (P < 0.001). The patients who underwent R0 resection gained a statistically longer survival time than those who did not (P < 0.001). Conclusions: Both classifications accurately reflect the clinical outcome of p-NETs. Surgical margin, the World Health Organization 2010 grading, and the TNM staging systems may all be meaningful prognostic factors impacting the long-term survival of patients with p-NETs.