A real-world, population-based study of the trends for incidence and prognosis in high-grade neuroendocrine tumor of cervix.

To explore the incidence and prognosis trends for high-grade cervical neuroendocrine tumor (HGCNET) and construct a nomogram to predict prognosis for HGCNET. Annual age-adjusted incidence of HGCNET from 1975 to 2015 was retrieved from the Surveillance, Epidemiology, and End Results program, the linear regression, poisson regression and annual percentage changes were used to assess the incidence trend. Also, trends for relative survival (RS) and overall survival (OS) in HGCNET patients from 1975 to 2015 were evaluated. From 1988 to 1975, 514 HGCNET patients were selected and divided into two cohorts with a ratio of 7:3. Nomogram to predict OS for these patients was constructed and validated. The incidence trend for HGCNET was unchanged in the past four decades (P = 0.734), but the proportion of HGCNET in diagnosed cervical cancer slightly increased from 0.9% in 1975 to 1.9% in 2015 (P < 0.001). The 5-year RS and OS for HGCNET in the study periods decreased steadily (RS: P = 0.009; OS: P = 0.008). Nomogram incorporating age, T stage, lymph-node positive, distant metastasis and surgery was constructed. The C-index of the nomogram was 0.716 (0.680-0.752), which was higher than the FIGO staging system. The incidence of HGCNET remained unchanged in the past four decades but the proportion of HGCNET has slightly increased. Besides, a steadily decreasing survival for HGCNET was observed in the study periods. A nomogram was constructed to better predict prognosis for HGCNET.