Retrospective Study
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Oct 28, 2019; 25(40): 6116-6128
Published online Oct 28, 2019. doi: 10.3748/wjg.v25.i40.6116
Apparent diffusion coefficient-based histogram analysis differentiates histological subtypes of periampullary adenocarcinoma
Jing-Yu Lu, Hao Yu, Xian-Lun Zou, Zhen Li, Xue-Mei Hu, Ya-Qi Shen, Dao-Yu Hu
Jing-Yu Lu, Hao Yu, Xian-Lun Zou, Zhen Li, Xue-Mei Hu, Ya-Qi Shen, Dao-Yu Hu, Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei Province, China
Jing-Yu Lu, Department of Radiology, the First Affiliated Hospital of Soochow University, Suzhou 215006, Jiangsu Province, China
Author contributions: All authors contributed to the design of the study; Lu JY and Shen YQ wrote the manuscript; Yu H and Hu XM contributed to the measurement; Lu JY and Zou XL contributed to data acquisition and prepared the tables and figures; Li Z, Shen YQ, and Hu DY revised the manuscript; all authors reviewed the manuscript and approved the final vision to be submitted.
Supported by the National Natural Science Foundation of China, No. 81701657, No. 81571642, No. 81801695, and No. 81771801; the Fundamental Research Funds for the Central Universities, No. 2017KFYXJJ126.
Institutional review board statement: This study was approved by the Ethics Committee of Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology.
Informed consent statement: All patients agreed to MR examination and treatment with written consent. Due to the retrospective nature of the present study, the additional informed consent was waived.
Conflict-of-interest statement: All authors declare no conflicts of interest related to this article.
Data sharing statement: No additional data are available.
Open-Access: This 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 Non Commercial (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: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Ya-Qi Shen, MD, PhD, Doctor, Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology,1095 Jiefang Avenue, Wuhan 430030, Hubei Province, China. yqshen@hust.edu.cn
Telephone: +86-27-83662640 Fax: +86-27-83662640
Received: July 23, 2019
Peer-review started: July 23, 2019
First decision: August 27, 2019
Revised: September 17, 2019
Accepted: September 27, 2019
Article in press: September 28, 2019
Published online: October 28, 2019
Abstract
BACKGROUND

For periampullary adenocarcinoma, the histological subtype is a better prognostic predictor than the site of tumor origin. Intestinal-type periampullary adenocarcinoma (IPAC) is reported to have a better prognosis than the pan-creatobiliary-type periampullary adenocarcinoma (PPAC). However, the classification of histological subtypes is difficult to determine before surgery. Apparent diffusion coefficient (ADC) histogram analysis is a noninvasive, non-enhanced method with high reproducibility that could help differentiate the two subtypes.

AIM

To investigate whether volumetric ADC histogram analysis is helpful for distinguishing IPAC from PPAC.

METHODS

Between January 2015 and October 2018, 476 consecutive patients who were suspected of having a periampullary tumor and underwent magnetic resonance imaging (MRI) were reviewed in this retrospective study. Only patients who underwent MRI at 3.0 T with different diffusion-weighted images (b-values = 800 and 1000 s/mm2) and who were confirmed with a periampullary adenocarcinoma were further analyzed. Then, the mean, 5th, 10th, 25th, 50th, 75th, 90th, and 95th percentiles of ADC values and ADCmin, ADCmax, kurtosis, skewness, and entropy were obtained from the volumetric histogram analysis. Comparisons were made by an independent Student's t-test or Mann-Whitney U test. Multiple-class receiver operating characteristic curve analysis was performed to determine and compare the diagnostic value of each significant parameter.

RESULTS

In total, 40 patients with histopathologically confirmed IPAC (n = 17) or PPAC (n = 23) were enrolled. The mean, 5th, 25th, 50th, 75th, 90th, and 95th percentiles and ADCmax derived from ADC1000 were significantly lower in the PPAC group than in the IPAC group (P < 0.05). However, values derived from ADC800 showed no significant difference between the two groups. The 75th percentile of ADC1000 values achieved the highest area under the curve (AUC) for differentiating IPAC from PPAC (AUC = 0.781; sensitivity, 91%; specificity, 59%; cut-off value, 1.50 × 10-3 mm2/s).

CONCLUSION

Volumetric ADC histogram analysis at a b-value of 1000 s/mm2 might be helpful for differentiating the histological subtypes of periampullary adenocarcinoma before surgery.

Keywords: Periampullary adenocarcinoma, Apparent diffusion coefficient, Histogram analysis, Histopathology, Differential diagnosis

Core tip: Two subtypes of periampullary adenocarcinoma were investigated in the present study: one is intestinal-type periampullary adenocarcinoma (IPAC), and the other is pancreatobiliary-type periampullary adenocarcinoma (PPAC). The aim of the present study was to distinguish these two subtypes by volumetric apparent diffusion coefficient (ADC) histogram analysis. Forty pathologically confirmed patients were enrolled. The mean, maximum, and various percentiles of ADC values derived from b1000 were lower in the PPAC group than in the IPAC group with statistical significance. The 75th percentile of ADC values achieved the highest area under the curve.