Evaluation of the prognosis for N2 status in patients with small bowel neuroendocrine tumors

Background: The 8th edition AJCC Staging for small bowel neuroendocrine tumors created a novel N2 classification. This study investigates if it is independently prognostic. Methods: Records of patients from 2008 to 2019 were reviewed. Survival rates were estimated by Kaplan-Meier method and compared by log-rank. The Cox Proportional Hazards model was used to determine factors associated with overall survival (OS) via multivariate analysis. Results: Among 300 patients, 225 were N2 and 60 were N1. No differences were seen in pathologic markers for N1 compared to N2. N2 were more likely to have liver metastases (LM) (p = 0.048) but rates of resectability were similar. Median OS for N1 with >70% liver cytoreduction was not yet reached compared to 121 months for N2 (p = 0.005). On multivariate analysis, LM was associated with shorter survival (p = 0.028), but nodal status was not. Conclusions: Unlike LM, N2 status is not independently prognostic, but a marker for aggressive LM.