Published online May 15, 2019. doi: 10.4251/wjgo.v11.i5.436
Peer-review started: January 30, 2019
First decision: March 14, 2019
Revised: March 19, 2019
Accepted: March 26, 2019
Article in press: March 26, 2019
Published online: May 15, 2019
Hepatic neuroendocrine neoplasm (hNEN) is a rare tumor clinically. It is important to identify the source and malignant degree of hNEN and distinguish it from hepatocellular carcinoma (HCC). Imaging examination is required for the initial screening of hNEN. However, there is a lack of data regarding imaging diagnosis of hNEN.
Because of the lack of imaging examination experience, the screening and identification of hNEN is difficult. Research has revealed that there are some differences among hNEN with different sources and malignant degrees screened by ultrasound and contrast-enhanced ultrasound (CEUS). By analyzing the characteristics of ultrasound and CEUS, our study hopes to provide more helpful information in the diagnosis of hNEN.
In this study, the ultrasound performance between hNEN and HCC and data of hNEN with different sources and malignant degrees were compared. The purpose of this study was to improve the accuracy of the identification of hNEN and provide useful information for its clinical diagnosis.
A total of 55 patients with hNEN were recruited, the hNEN group. There were 35 cases in the hepatic neuroendocrine tumor (hNET) group, and 20 cases in the neuroendocrine carcinoma (hNEC) group. About 55 patients with HCC were recruited as the HCC group. The characteristic differences of B-mode ultrasound and CEUS between hNEN and HCC, hNEN from different sources, and between hNEC and hNET were compared and analyzed.
Compared with the HCC group, the proportions of multiple liver lesions, unclear borders, and high echo lesions were higher and the proportions of non-uniform echo and peripheral acoustic halo were lower in the hNEN group. In the NEN group, the washout to iso-enhancement time and washout to hypo-enhancement time were lower than those of the HCC group. The proportion of low enhancement of portal venous phase, non-uniform enhancement forms, and combined tumor vasculature in the hNEC group was greater than that in the hNEN group.
Compared with HCC, the ultrasound performance of hNEN showed more intrahepatic lesions, uniform high echo, uniform high enhancement at arterial phase, and rapid washout. Compared with hNET, the CEUS characteristics of hNEC are low enhancement of portal venous phase, non-uniform enhancement forms, and combined tumor vasculature.
To expand this research, future studies should include more hospitals in order to collect detailed data from more hNEN patients. The ultrasound results of primary hNEN also need to be analyzed further to provide stronger evidence for clinical diagnosis.