Retrospective Study
Copyright ©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Mar 14, 2023; 29(10): 1602-1613
Published online Mar 14, 2023. doi: 10.3748/wjg.v29.i10.1602
Quantitative parameters in novel spectral computed tomography: Assessment of Ki-67 expression in patients with gastric adenocarcinoma
Li-Ting Mao, Wei-Cui Chen, Jian-Ye Lu, Han-Liang Zhang, Yong-Song Ye, Yu Zhang, Bo Liu, Wei-Wei Deng, Xian Liu
Li-Ting Mao, Wei-Cui Chen, Jian-Ye Lu, Han-Liang Zhang, Yong-Song Ye, Bo Liu, Xian Liu, Department of Radiology, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510120, Guangdong Province, China
Yu Zhang, Department of Pathology, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510120, Guangdong Province, China
Wei-Wei Deng, Department of Scientific Research, Clinical & Technical Support, Philips Healthcare China, Shanghai 200040, China
Author contributions: Mao LT, Chen WC and Liu B designed the research; Lu JY, Zhang HL, Ye YS, and Deng WW collected the data; Mao LT and Liu X analyzed the data and wrote the manuscript; and all authors have read and approved the final manuscript.
Institutional review board statement: This retrospective study was approved by Institutional Review Board of our hospital (approval No.AF/04-07.0/10.0).
Informed consent statement: This informed consent was waived by Institutional Review Board of our hospital.
Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article.
Data sharing statement: No additional data are available.
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: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Xian Liu, PhD, Professor, Department of Radiology, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, No. 111 Dade Road, Yuexiu District, Guangzhou 510120, Guangdong Province, China. liuxian74@hotmail.com
Received: August 29, 2022
Peer-review started: August 29, 2022
First decision: December 12, 2022
Revised: December 23, 2022
Accepted: January 16, 2023
Article in press: January 16, 2023
Published online: March 14, 2023
Abstract
BACKGROUND

The level of Ki-67 expression has served as a prognostic factor in gastric cancer. The quantitative parameters based on the novel dual-layer spectral detector computed tomography (DLSDCT) in discriminating the Ki-67 expression status are unclear.

AIM

To investigate the diagnostic ability of DLSDCT-derived parameters for Ki-67 expression status in gastric carcinoma (GC).

METHODS

Dual-phase enhanced abdominal DLSDCT was performed preoperatively in 108 patients with gastric adenocarcinoma. Primary tumor monoenergetic CT attenuation value at 40-100 kilo electron volt (kev), the slope of the spectral curve (λHU), iodine concentration (IC), normalized IC (nIC), effective atomic number (Zeff) and normalized Zeff (nZeff) in the arterial phase (AP) and venous phase (VP) were retrospectively compared between patients with low and high Ki-67 expression in gastric adenocarcinoma. Spearman’s correlation coefficient was used to analyze the association between the above parameters and Ki-67 expression status. Receiver operating characteristic (ROC) curve analysis was performed to compare the diagnostic efficacy of the statistically significant parameters between two groups.

RESULTS

Thirty-seven and 71 patients were classified as having low and high Ki-67 expression, respectively. CT40 kev-VP, CT70 kev-VP, CT100 kev-VP, and Zeff-related parameters were significantly higher, but IC-related parameters were lower in the group with low Ki-67 expression status than the group with high Ki-67 expression status, and other analyzed parameters showed no statistical difference between the two groups. Spearman’s correlation analysis showed that CT40 kev-VP, CT70 kev-VP, CT100 kev-VP, Zeff, and nZeff exhibited a negative correlation with Ki-67 status, whereas IC and nIC had positive correlation with Ki-67 status. The ROC analysis demonstrated that the multi-variable model of spectral parameters performed well in identifying the Ki-67 status [area under the curve (AUC) = 0.967; sensitivity 95.77%; specificity 91.89%)]. Nevertheless, the differentiating capabilities of single-variable model were moderate (AUC value 0.630 - 0.835). In addition, the nZeffVP and nICVP (AUC 0.835 and 0.805) showed better performance than CT40 kev-VP, CT70 kev-VP and CT100 kev-VP (AUC 0.630, 0.631 and 0.662) in discriminating the Ki-67 status.

CONCLUSION

Quantitative spectral parameters are feasible to distinguish low and high Ki-67 expression in gastric adenocarcinoma. Zeff and IC may be useful parameters for evaluating the Ki-67 expression.

Keywords: Spectral computer tomography, Quantitative parameters, Gastric carcinoma, Iodine concentration, Effective atomic number, Ki-67 expression

Core Tip: This is a retrospective study to preoperatively distinguish the expression of Ki-67 index based on the parameters of spectral computer tomography (CT) in patients with gastric adenocarcinoma. The CT attenuation of virtual monoenergetic images in venous phase and effective atomic number were negatively related to the expression of Ki-67, while iodine concentration exhibited positive associations with it. Multi-variable model of spectral parameters exhibited a better diagnostic efficiency than other single-variable model of spectral parameter in discriminating low and high Ki-67 expression in gastric adenocarcinoma.