Manzini G, Hapke F, Hines IN, Henne-Bruns D, Kremer M. Adjuvant chemotherapy in curatively resected rectal cancer: How valid are the data? World J Gastrointest Oncol 2020; 12(4): 503-513 [PMID: 32368327 DOI: 10.4251/wjgo.v12.i4.503]
Corresponding Author of This Article
Giulia Manzini, MD, MSc, Doctor, Surgeon, Department of General and Visceral Surgery, University of Ulm, Albert-Einstein-Allee 23, Ulm 89081, Germany. giulia.manzini@uniklinik-ulm.de
Research Domain of This Article
Methodology
Article-Type of This Article
Evidence-Based Medicine
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 Oncol. Apr 15, 2020; 12(4): 503-513 Published online Apr 15, 2020. doi: 10.4251/wjgo.v12.i4.503
Adjuvant chemotherapy in curatively resected rectal cancer: How valid are the data?
Giulia Manzini, Fabius Hapke, Ian N Hines, Doris Henne-Bruns, Michael Kremer
Giulia Manzini, Fabius Hapke, Doris Henne-Bruns, Michael Kremer, Department of General and Visceral Surgery, University of Ulm, Ulm 89081, Germany
Ian N Hines, Department of Nutrition Science, College of Allied Health Sciences, East Carolina University, Greenville, NC 27834, United States
Michael Kremer, Department of General and Visceral Surgery, Hospital of Aarau, Aarau 5000, Switzerland
Author contributions: Manzini G, Kremer M and Henne-Bruns D contributed substantially to the conception and design of the study; Manzini G and Hapke F contributed to the analysis and interpretation of the data; Manzini G performed the meta-analysis; Manzini G, Hines IN and Kremer M wrote the manuscript; all authors gave their final approval of the version to be published.
Conflict-of-interest statement: The authors declare that they have no competing interests
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: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Giulia Manzini, MD, MSc, Doctor, Surgeon, Department of General and Visceral Surgery, University of Ulm, Albert-Einstein-Allee 23, Ulm 89081, Germany. giulia.manzini@uniklinik-ulm.de
Received: November 7, 2019 Peer-review started: November 7, 2019 First decision: December 5, 2019 Revised: February 27, 2020 Accepted: March 22, 2020 Article in press: March 22, 2020 Published online: April 15, 2020
ARTICLE HIGHLIGHTS
Research background
The use of chemotherapy (CTx) after curative surgery for non-metastatic rectal cancer and its role in improving patient survival remains controversial.
Research motivation
In 2012, Petersen et al[3] reported in a Cochrane review the effect of postoperative adjuvant CTx following curatively resected rectal cancer (Tany, Nany, M0) on overall survival. The authors identified 21 randomized controlled trials (RCT) reporting overall survival as primary endpoint. The meta-analysis of these RCTs showed a significant reduction in the risk of death (17%) among patients undergoing postoperative CTx as compared to those undergoing observation (hazard ratio = 0.83; 95% confidence interval: 0.76-0.91).
Research objectives
We aimed to analyze the quality of the data supporting the advantage of adjuvant CTx after surgery for rectal cancer.
Research methods
Using the CONSORT Checklist, the current analysis evaluated the validity of the three most powerful studies reviewed and analyzed within the Cochrane review by Petersen et al[3] 2012 which support the survival benefit of adjuvant CTx.
Research results
The detailed analysis of the three most powerful studies highlighted inconsistencies including inappropriate answers in up to 47% of the items of the CONSORT checklist. Inadequate or unclear randomization without allocation concealment, missing blinded set-up, absence of intention-to-treat analysis and omission of sample size calculation were the most common findings.
Research conclusions
We suggest a more critical appraisal regarding the validity of single RCTs, as these studies are included in meta-analysis that are the basis for guidelines.
Research perspectives
As CTx has several side effects for the patient and generates costs for the health system, it should be used only if its benefit is real.
