Chok AY, Zhao Y, Chen HLR, Tan IEH, Chew DHW, Zhao Y, Au MKH, Tan EJKW. Elderly patients over 80 years undergoing colorectal cancer resection: Development and validation of a predictive nomogram for survival. World J Gastrointest Surg 2023; 15(5): 892-905 [PMID: 37342856 DOI: 10.4240/wjgs.v15.i5.892]
Corresponding Author of This Article
Aik Yong Chok, FRCS (Ed), MBBS, MMed, Surgeon, Department of Colorectal Surgery, Singapore General Hospital, Academia, 20 College Road, Singapore 169608, Singapore. chokaikyong@gmail.com
Research Domain of This Article
Surgery
Article-Type of This Article
Retrospective Study
Open-Access Policy of This Article
This article is an open-access article which 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/
World J Gastrointest Surg. May 27, 2023; 15(5): 892-905 Published online May 27, 2023. doi: 10.4240/wjgs.v15.i5.892
Elderly patients over 80 years undergoing colorectal cancer resection: Development and validation of a predictive nomogram for survival
Aik Yong Chok, Yun Zhao, Hui Lionel Raphael Chen, Ivan En-Howe Tan, Desmond Han Wen Chew, Yue Zhao, Marianne Kit Har Au, Emile John Kwong Wei Tan
Aik Yong Chok, Yun Zhao, Hui Lionel Raphael Chen, Yue Zhao, Emile John Kwong Wei Tan, Department of Colorectal Surgery, Singapore General Hospital, Singapore 169608, Singapore
Yun Zhao, Ivan En-Howe Tan, Desmond Han Wen Chew, Group Finance Analytics, Singapore Health Services, Singapore 168582, Singapore
Marianne Kit Har Au, Group Finance, Singapore Health Services, Singapore 168582, Singapore
Marianne Kit Har Au, Singhealth Community Hospitals, Singapore 168582, Singapore
Author contributions: Chok AY designed the study and interpreted the data; Zhao Y performed the analysis and visualization; Chen HLR and Zhao Y performed the literature review; Tan IEH, Chew DHW, Au MKH collected the clinical data; Chok AY, Zhao Y, Chen HLR, and Zhao Y drafted the manuscript; Chok AY, Zhao Y and Tan EJKW edited the manuscript; Chok AY and Tan EJKW provided critical revision for final approval; all authors have read and approved the final version of the manuscript.
Institutional review board statement: This study was approved by Singapore Health Services (SingHealth) Institutional Review Board (IRB Ref. 2022/2438). All methods were carried out in accordance with relevant guidelines and regulations (Declaration of Helsinki).
Informed consent statement: Due to the study’s retrospective design using de-identified data, written informed consent collection was waived by SingHealth Centralised Institutional Review Board.
Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article.
Data sharing statement: The data are not publicly available due to privacy and ethical restrictions.
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: Aik Yong Chok, FRCS (Ed), MBBS, MMed, Surgeon, Department of Colorectal Surgery, Singapore General Hospital, Academia, 20 College Road, Singapore 169608, Singapore. chokaikyong@gmail.com
Received: December 3, 2022 Peer-review started: December 3, 2022 First decision: February 1, 2023 Revised: February 27, 2023 Accepted: March 27, 2023 Article in press: March 27, 2023 Published online: May 27, 2023 Processing time: 174 Days and 6.7 Hours
Abstract
BACKGROUND
Surgery remains the primary treatment for localized colorectal cancer (CRC). Improving surgical decision-making for elderly CRC patients necessitates an accurate predictive tool.
AIM
To build a nomogram to predict the overall survival of elderly patients over 80 years undergoing CRC resection.
METHODS
Two hundred and ninety-five elderly CRC patients over 80 years undergoing surgery at Singapore General Hospital between 2018 and 2021 were identified from the American College of Surgeons – National Surgical Quality Improvement Program (ACS-NSQIP) database. Prognostic variables were selected using univariate Cox regression, and clinical feature selection was performed by the least absolute shrinkage and selection operator regression. A nomogram for 1- and 3-year overall survival was constructed based on 60% of the study cohort and tested on the remaining 40%. The performance of the nomogram was evaluated using the concordance index (C-index), area under the receiver operating characteristic curve (AUC), and calibration plots. Risk groups were stratified using the total risk points derived from the nomogram and the optimal cut-off point. Survival curves were compared between the high- and low-risk groups.
RESULTS
Eight predictors: Age, Charlson comorbidity index, body mass index, serum albumin level, distant metastasis, emergency surgery, postoperative pneumonia, and postoperative myocardial infarction, were included in the nomogram. The AUC values for the 1-year survival were 0.843 and 0.826 for the training and validation cohorts, respectively. The AUC values for the 3-year survival were 0.788 and 0.750 for the training and validation cohorts, respectively. C-index values of the training cohort (0.845) and validation cohort (0.793) suggested the excellent discriminative ability of the nomogram. Calibration curves demonstrated a good consistency between the predictions and actual observations of overall survival in both training and validation cohorts. A significant difference in overall survival was seen between elderly patients stratified into low- and high-risk groups (P < 0.001).
CONCLUSION
We constructed and validated a nomogram predicting 1- and 3-year survival probability in elderly patients over 80 years undergoing CRC resection, thereby facilitating holistic and informed decision-making among these patients.
Core Tip: This is the first predictive nomogram evaluating the survival outcomes among elderly colorectal cancer patients over 80 years. This nomogram has incorporated age, Charlson comorbidity index, body mass index, serum albumin level, the presence of metastatic disease, emergency surgery, as well as postoperative pneumonia and myocardial infarction. Our study is the first to link these variables together in predicting overall survival in elderly colorectal cancer patients over 80 years. This novel nomogram that accurately predicts survival probabilities may facilitate preoperative treatment decisions in the advancing age group.
