Abstract: ObjectiveTo investigate the prognosis factors of patients with nonfunctional pancreatic neuroendocrine carcinoma (NFPanNEC). MethodsThe patients with NFPanNEC confirmed by pathology from 2004 to 2015 were collected from the Surveillance, Epidemiology, and End Results (SEER) database of the American National Cancer Institute. The MatchIt package in the R software was used to perform propensitymatching analysis of surgery, radiotherapy and chemotherapy. The KaplanMeier method was used to calculate the cumulative survival rate, and the significant difference was evaluated by the logrank test. Then the Cox multivariate regression analysis was applied to evaluate the prognostic factors of NFPanNEC patients. ResultsA total of 2 603 NFPanNEC patients were included in the analysis. Univariate analysis showed that the age of diagnosis (χ2=123.8, P<0.001), gender (χ2=7.3, P=0.007), marital status (χ2=26.7, P<0.001),  primary site of tumor (χ2=47.8, P<0.001), degree of tumor differentiation (χ2=628.7, P<0.001),  American Joint Committee on Cancer (AJCC) stage (χ2=811.7, P<0.001), T stage (χ2=425.9, P<0.001), N stage (χ2=272.3, P<0.001), M stage (χ2=779.8, P<0.001), surgery (χ2=962.6, P<0.001), chemotherapy (χ2=21.9, P<0.001) were associated with the prognosis of NFPanNEC patients. No correlation was observed between radiotherapy and the prognosis of NFPanNEC patients (χ2=0.1, P=0.750). Multivariate Cox regression analysis showed that older diagnostic age (≥74 years old vs. ≤56 years old, HR=2.20, 95%CI: 1.842.62, P<0.001), male (male vs. female, HR=1.14, 95%CI为1.01~1.29, P=0.035), single or divorced or widowed (single or divorced vs. married, HR=1.26, 95%CI: 1.101.45, P=0.001; widowed vs. married, HR=1.29, 95%CI: 1.041.61, P=0.022), head of pancreas (tail of pancreas vs. head of pancreas, HR=0.85, 95%CI: 0.730.99, P=0.033), poor differentiation (grade Ⅳ vs. grade Ⅰ, HR=3.75, 95%CI: 2.705.20, P<0.001), late AJCC stage (stage Ⅳ vs. stage Ⅰ, HR=5.72, 95%CI: 4.237.73, P<0.001), no surgery treatment (yes vs. no, HR=0.37, 95%CI: 0.300.44, P<0.001) were significant prognostic risk factors for NFPanNEC patients, and chemotherapy was not independent prognostic factor (yes vs. no, HR=1.00, 95%CI: 0.881.13, P=0.958). ConclusionThe older diagnostic age, single or divorced or windowed, head of pancreas, poor differentiation, late AJCC stage and no surgery treatment are significant prognostic risk factors for NFPanNEC patients. Radiotherapy and chemotherapy may not improve the prognosis of NFPanNEC patients.

Key words: Pancreatic neoplasms, Carcinoma, neuroendocrine, Prognosis, SEER program