Observational Study
Copyright ©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Surg. Sep 27, 2023; 15(9): 2032-2041
Published online Sep 27, 2023. doi: 10.4240/wjgs.v15.i9.2032
Comparative detection of syndecan-2 methylation in preoperative and postoperative stool DNA in patients with colorectal cancer
Ji Hyeong Song, Tae Jeong Oh, Sungwhan An, Kyung Ha Lee, Ji Yeon Kim, Jin Soo Kim
Ji Hyeong Song, Jin Soo Kim, Department of Surgery, Chungnam National University Sejong Hospital, Sejong 30099, South Korea
Tae Jeong Oh, Sungwhan An, Genomictree, Inc., Daejeon 34027, South Korea
Kyung Ha Lee, Ji Yeon Kim, Jin Soo Kim, Department of Surgery, College of Medicine, Chungnam National University, Daejeon 35015, South Korea
Author contributions: Song JH collected and analyzed the clinical data, drafted the manuscript, and prepared the figures; Oh TJ and An S drafted the manuscript; Lee KH and Kim JY collected the stool samples; Kim JS participated in study design, collected the stool samples, collected and analyzed the clinical data, drafted the manuscript, and prepared the figures; All authors read and approved the final manuscript.
Supported by the Research Fund of Chungnam National University, No. 2018-0626-01.
Institutional review board statement: This observational study was approved by the Institutional Review Board of our institute (IRB No. 2016-05-018).
Informed consent statement: Written informed consent was obtained from all subjects.
Conflict-of-interest statement: The authors declare that they have no competing interests.
STROBE statement: The authors have read the STROBE Statement-checklist of items, and the manuscript was prepared and revised according to the STROBE Statement-checklist of items.
Corresponding author: Jin Soo Kim, MD, PhD, Assistant Professor, Surgery, Chungnam National University Sejong Hospital, 20, Bodeum 7-ro, Sejong-si, Republic of Korea, Sejong 30099, South Korea. jskim7562@gmail.com
Received: June 8, 2023
Peer-review started: June 8, 2023
First decision: July 7, 2023
Revised: July 13, 2023
Accepted: August 4, 2023
Article in press: August 4, 2023
Published online: September 27, 2023
ARTICLE HIGHLIGHTS
Research background

Colorectal cancer (CRC) is a significant cause of morbidity and mortality worldwide, emphasizing the need for early detection. Stool DNA (sDNA) testing is a promising non-invasive method for CRC detection, and syndecan-2 (SDC2) methylation has been identified as a potential biomarker for this test.

Research motivation

The study aimed to investigate whether SDC2 methylation in sDNA normalizes after surgical resection of CRC, which could have implications for the diagnostic value and postoperative surveillance of SDC2 methylation.

Research objectives

The study aimed to compare the detection rates of SDC2 methylation in preoperative and postoperative stool samples of CRC patients and assess the association between SDC2 methylation and clinicopathological parameters. The study also sought to evaluate the change in SDC2 methylation levels before and after surgery.

Research methods

A prospective study enrolled 151 CRC patients who underwent surgical resection. Stool samples were collected before and after surgery, and SDC2 methylation in sDNA was assessed using a quantitative methylation-specific real-time polymerase chain reaction. The association between SDC2 methylation and clinicopathological parameters was analyzed.

Research results

The detection rate of SDC2 methylation was significantly higher in preoperative stool samples (88.6%) compared to postoperative samples (19.7%). Large tumor size and advanced T stage were associated with higher detection rates before surgery, while female sex was associated with false positives after surgery. The cycle threshold (CT) values significantly decreased after surgery, indicating a normalization of SDC2 methylation. The postoperative negative conversion rate for preoperatively methylated SDC2 was 79.3%.

Research conclusions

The study findings suggest that the SDC2 methylation test in sDNA has acceptable sensitivity and specificity for CRC detection. However, the detection rate is lower for small-size and early T stage tumors. The significant decrease in CT values after surgery indicates the diagnostic value of SDC2 methylation testing for CRC.

Research perspectives

Further research is needed to validate the findings and assess the long-term utility of SDC2 methylation testing as a surveillance tool for postoperative CRC patients. Multicenter prospective studies with extended follow-up periods are warranted to evaluate the feasibility and effectiveness of SDC2 methylation testing in clinical practice.