Comparison of clinical pathological features, surgical treatments and prognosis of Gallbladder Neuroendocrine Neoplasms between Chinese and American population: Based on a nationwide multicenter study and SEER database.

Abstract

e16119 Background: Gallbladder Neuroendocrine Neoplasm (GB-NEN) is an extremely rare type of gallbladder neoplasms and its characteristics and prognosis varies widely. The focus of this study was to analyze and compare the clinical pathological features, surgical treatments and prognosis of patients with GB-NEN between Chinese and American population. Methods: The Chinese Research Group of Gallbladder Cancer (CRGGC) study is a multicenter retrospective registry cohort study reviewing the electronic medical records from 76 tertiary and secondary hospitals across 28 provinces in China. Patients diagnosed with GB-NEN according to the 2019 WHO classification between 2010 and 2017 were assembled from CRGGC study and National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) database. Chi-square test for categorical variables and the overall survival outcomes were analyzed by the Kaplan–Meier method in the two groups before and after a propensity score matching (PSM) with 1:1 ratio. Results: In this study, we assembled totally 84 patients from CRGGC study and there were 217 patients with GB-NEN diagnosed during the same period from National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) database. After the PSM using sex, age, American Joint Committee on Cancer stage 7th Edition, liver invasion status and types of surgical treatment, 19 pairs of patients were included. Chinese patients from the CRGGC with GB-NENs presents more liver invasion (c²= 22.621, P = 0.000), higher diagnosed age (c²= 37.313, P = 0.000) and cancer stage (c²= 13.298, P = 0.021) totally than those from the SEER database. Radical surgical treatments were performed in 51(60.714%) and 96(44.240%) patients among patients from the CRGGC study and the SEER database respectively and the surgical treatment model shows a difference between these two groups (c²= 85.729, P = 0.000). Compared with propensity score matched American patients with GB-NENs from SEER database, Chinese patients from the CRGGC study had similar overall survival(c²= 0.480, P = 0.489) instead of longer overall survival than patients from the SEER database before PSM(c²= 6.408, P = 0.011). Conclusions: Chinese and American patients with GB-NEN form the CRGGC study and the SEER database present no difference in overall survival after PSM. However, heterogeneity of pathological features, surgical treatments between those groups of GB-NEN patients prompt that different methods could be referred for the improvement in the survival of GB-NEN patients.