Published online May 27, 2019. doi: 10.4240/wjgs.v11.i5.247
Peer-review started: April 2, 2019
First decision: April 20, 2019
Revised: May 9, 2019
Accepted: May 23, 2019
Article in press: May 23, 2019
Published online: May 27, 2019
With advanced age and chronic illness, the life expectancy of a patient with colorectal cancer (CRC) becomes less dependent on the malignant disease and more on their pre-morbid condition. Justifying major surgery for these elderly patients can be challenging. An accurate tool demonstrating post-operative survival probability would be useful for surgeons and their patients.
To integrate clinically significant prognostic factors relevant to elective colorectal surgery in the elderly into a validated pre-operative scoring system.
In this retrospective cohort study, patients aged 70 and above who underwent surgery for CRC at Singapore General Hospital between 1 January 2005 and 31 December 2012 were identified from a prospectively maintained database. Patients with evidence of metastatic disease, and those who underwent emergency surgery or had surgery for benign colorectal conditions were excluded from the analysis. The primary outcome was overall 3-year overall survival (OS) following surgery. A multivariate model predicting survival was derived and validated against an equivalent external surgical cohort from Kyungpook National University Chilgok Hospital, South Korea. Statistical analyses were performed using Stata/MP Version 15.1.
A total of 1267 patients were identified for analysis. The median post-operative length of stay was 8 [interquartile range (IQR) 6-12] d and median follow-up duration was 47 (IQR 19-75) mo. Median OS was 78 (IQR 65-85) mo. Following multivariate analysis, the factors significant for predicting overall mortality were serum albumin < 35 g/dL, serum carcinoembryonic antigen ≥ 20 µg/L, T stage 3 or 4, moderate tumor cell differentiation or worse, mucinous histology, rectal tumors, and pre-existing chronic obstructive lung disease. Advanced age alone was not found to be significant. The Korean cohort consisted of 910 patients. The Singapore cohort exhibited a poorer OS, likely due to a higher proportion of advanced cancers. Despite the clinicopathologic differences, there was successful validation of the model following recalibration. An interactive online calculator was designed to facilitate post-operative survival prediction, available at http://bit.ly/sgh_crc. The main limitation of the study was selection bias, as patients who had undergone surgery would have tended to be physiologically fitter.
This novel scoring system generates an individualized survival probability following colorectal resection and can assist in the decision-making process. Validation with an external population strengthens the generalizability of this model.
Core tip: Ageing results in a decreased functional reserve along with various comorbid diseases. Many elderly patients express age-related concerns when advised for operative intervention. This is the first predictive survival model specific for older patients planned for elective colorectal surgery and provides a visual guide to facilitate the counselling process.
Seow-En I, Tan WJ, Dorajoo SR, Soh SHL, Law YC, Park SY, Choi GS, Tan WS, Tang CL, Chew MH. Prediction of overall survival following colorectal cancer surgery in elderly patients. World J Gastrointest Surg 2019; 11(5): 0000-0000 URL: https://http://www.wjgnet.com/1948-9366/full/v11/i5/0000.htm DOI: https://dx.doi.org/10.4240/wjgs.v11.i5.0000