Retrospective Study
Copyright ©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Oncol. Jul 15, 2022; 14(7): 1324-1336
Published online Jul 15, 2022. doi: 10.4251/wjgo.v14.i7.1324
Effect of obesity on post-operative outcomes following colorectal cancer surgery
Derek Mao, David E Flynn, Stephanie Yerkovich, Kayla Tran, Usha Gurunathan, Manju D Chandrasegaram
Derek Mao, Faculty of Medicine and Health, The University of Sydney, Sydney 2050, New South Wales, Australia
David E Flynn, Manju D Chandrasegaram, Department of General Surgery, The Prince Charles Hospital, Brisbane 4032, Queensland, Australia
Stephanie Yerkovich, Usha Gurunathan, Manju D Chandrasegaram, Faculty of Medicine, The University of Queensland, Brisbane 4006, Queensland, Australia
Kayla Tran, Department of Pathology, The Prince Charles Hospital, Brisbane 4032, Queensland, Australia
Usha Gurunathan, Department of Anaesthesia, The Prince Charles Hospital, Brisbane 4032, Queensland, Australia
Author contributions: Mao D designed the study, performed the research, and wrote the manuscript; Flynn DE designed the study methodology and helped perform the research; Yerkovich S helped with data collection, statistical analysis, and manuscript review; Tran K and Gurunathan U helped with data collection, clinical advice, data analysis, and manuscript review; Chandrasegaram MD helped with design methodology and conceptualization, study supervision, manuscript editing and finalization.
Institutional review board statement: Ethics approval for this database was granted by the Prince Charles Hospital Human Research Ethics Committee (Approval No. HREC/17/QPCH/295).
Informed consent statement: I certify that patients were not required to give informed consent to the study because the analysis used anonymous clinical data that was obtained after each patient agreed to treatment by written consent.
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:
Corresponding author: Manju D Chandrasegaram, FRCS, MBChB, Attending Doctor, Senior Lecturer, Surgeon, Department of General Surgery, The Prince Charles Hospital, Rode Road, Brisbane 4032, Queensland, Australia.
Received: November 22, 2021
Peer-review started: November 22, 2021
First decision: December 27, 2021
Revised: January 10, 2022
Accepted: June 18, 2022
Article in press: June 18, 2022
Published online: July 15, 2022
Research background

Obesity is a worldwide epidemic of increasing significance. Although the colorectal surgeons of today manage a greater number of obese patients with colorectal cancer (CRC), the current literature reports inconsistent findings on whether this phenomenon impacts post-operative outcomes following CRC surgery.

Research motivation

This research was conducted to determine whether obese patients had equivalent outcomes compared to non-obese patients following CRC surgery. This is an important issue, as there is no consensus on whether obesity truly impacts post-operative outcomes, yet obese patients are at risk of having their surgery withheld or delayed based on this factor alone.

Research objectives

The primary aim of this study was to compare the post-operative outcomes of obese vs non-obese patients following CRC surgery. With laparoscopic surgery now recognized as the standard of care in CRC management, post-operative outcomes between obese and non-obese patients were also analyzed in the subgroup of patients undergoing laparoscopic CRC surgery.

Research methods

Patients who underwent CRC resection between January 2010 and December 2020 at the Prince Charles Hospital, Queensland, Australia were included in this study. As per the World Health Organization definition, this study defined obesity as a body mass index (BMI) ≥ 30 mg/kg2. Patients were divided into an obese and non-obese group, and post-operative outcomes were compared between these two groups using parametric and non-parametric tests. This study also analyzed the post-operative outcomes of obese vs non-obese patients in the subgroup undergoing laparoscopic CRC surgery.

Research results

This research has demonstrated that although obese patients were more likely to experience conversion to an open procedure (P = 0.002), they did not experience more post-operative complications (P = 0.06) or high-grade complications (P = 0.11). There were also no differences in in-hospital mortality (P = 0.06) or length of stay (P = 0.42). In the laparoscopic subgroup however, patients were more likely to experience a post-operative complication (P = 0.05), but did not experience more high-grade complications (P = 0.07).

Research conclusions

Our study has determined that obesity is no barrier to adequate post-operative outcomes following CRC surgery, with obese patients having equivalent post-operative outcomes compared to their non-obese counterparts. Caution is advised however, when attempting a laparoscopic approach in obese patients.

Research perspectives

Although BMI is a well-recognized and accepted surrogate marker of obesity, further studies in this area should analyze post-operative outcomes using other markers of visceral obesity. In addition, the effect of nutritional status and body composition on post-operative outcomes can be explored.