Retrospective Cohort Study
Copyright ©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Jul 7, 2020; 26(25): 3638-3649
Published online Jul 7, 2020. doi: 10.3748/wjg.v26.i25.3638
Functionality is not an independent prognostic factor for pancreatic neuroendocrine tumors
Hong-Yu Chen, Ya-Liang Zhou, Yong-Hua Chen, Xing Wang, Hao Zhang, Neng-Wen Ke, Xu-Bao Liu, Chun-Lu Tan
Hong-Yu Chen, Ya-Liang Zhou, Yong-Hua Chen, Xing Wang, Hao Zhang, Neng-Wen Ke, Xu-Bao Liu, Chun-Lu Tan, Department of Pancreatic Surgery, West China Hospital, Sichuan University, Chengdu 610041, Sichuan Province, China
Author contributions: Chen HY and Zhou YL contributed equally to this work; Liu XB, Tan CL, and Wang X designed the study; Chen HY, Zhou YL, Wang X, and Zhang H acquired the data; Chen HY, Zhou YL, and Wang X analyzed and interpreted the data; Chen HY and Zhou YL wrote the paper; Liu XB, Tan CL, and Chen YH critically revised the manuscript for important intellectual content; all authors have read and approved the version to be submitted.
Supported by 1.3.5 Project for Disciplines of Excellence, West China Hospital, Sichuan University, China, No. ZY2017302 1-3-5; and the Key Research and Development Projects of Sichuan Province, China, No. 2017SZ0132 and No. 2019YFS0042.
Institutional review board statement: This study was reviewed and approved by the West China Hospital Review Board.
Informed consent statement: Study participants of the West China Hospital database provided written informed consent prior to study enrollment.
Conflict-of-interest statement: The authors declare no conflicts of interest.
Data sharing statement: No additional data are available.
STROBE statement: The authors have read the STROBE Statement, and the manuscript was prepared and revised according to the STROBE Statement.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:
Corresponding author: Chun-Lu Tan, MD, Associate Professor, Department of Pancreatic Surgery, West China Hospital, Sichuan University, No. 37, Guoxue Lane, Wuhou District, Chengdu 610041, Sichuan Province, China.
Received: January 10, 2020
Peer-review started: January 10, 2020
First decision: March 6, 2020
Revised: May 8, 2020
Accepted: June 9, 2020
Article in press: June 9, 2020
Published online: July 7, 2020
Research background

Pancreatic neuroendocrine neoplasms (pNENs) that produce hormones leading to symptoms are classified as functional tumors, while others are classified as nonfunctional tumors.

Research motivation

The traditional view is that functionality affects the prognosis of pNEN patients. However, recent studies have proposed new viewpoints. Because of the rarity of pNENs and the low proportion of functional tumors, few studies have performed multivariate Cox regression to show the effect of functionality on survival.

Research objectives

To assess whether functionality is an independent factor for predicting the prognosis of pNEN patients.

Research methods

From January 2004 to December 2016, data of patients who underwent surgery at the primary site for the treatment of pNENs from the Surveillance, Epidemiology, and End Results (SEER) database and West China Hospital database were retrospectively analyzed.

Research results

From the SEER database, age and T stage were independent risk factors affecting the survival. From the West China Hospital database, independent prognostic factors were age, sex, and grade. The result of the cohort consisting of the combined populations from the two databases showed that race, age, sex, and T stage were independent prognostic factors. In the West China Hospital database and in the total population, nonfunctional pNETs and other functional pNETs tended to have poorer prognoses than insulinomas. However, functionality was not associated with the survival time of patients with pNETs in the multivariate analysis.

Research conclusions

Race, age, sex, and T stage are independent factors for predicting the survival of patients with pNETs. The results of this study do not support the opinion that hormone related syndrome is an efficacious tool to classify tumors into groups with different prognoses.

Research perspectives

Hormone related syndrome is the only basis to assess the functionality of neuroendocrine neoplasms. Nonfunctional tumors and functional tumors were reported to have different prognoses. However, they do not have much difference in pathologic feature or gene expression. Immunohistochemical staining also displays the expression of insulin/glucagon/gastrin/somatostatin in non-functional tumors. The reasonability of classification based on symptoms rather than gene expression needs to be further explored.