Retrospective Cohort Study
Copyright ©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Oncol. Apr 15, 2020; 12(4): 405-423
Published online Apr 15, 2020. doi: 10.4251/wjgo.v12.i4.405
Primary tumor location and survival in colorectal cancer: A retrospective cohort study
Himani Aggarwal, Kristin M Sheffield, Li Li, David Lenis, Rachael Sorg, Afsaneh Barzi, Rebecca Miksad
Himani Aggarwal, Kristin M Sheffield, Li Li, Eli Lilly and Company, Indianapolis, IN 46225, United States
David Lenis, Rachael Sorg, Rebecca Miksad, Flatiron Health, New York, NY 10013, United States
Afsaneh Barzi, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, United States
Author contributions: Aggarwal H, Sheffield KM, Li L, Lenis D, Sorg R, and Miksad R conceived and designed the analysis; Lenis D and Sorg R collected the data and executed the analysis; all the authors interpreted the data and contributed to the writing of the manuscript.
Institutional review board statement: This study was performed under the ethics approval of Copernicus Group IRB.
Informed consent statement: Patients were not required to give informed consent to the study because the analysis used anonymous data that was obtained after each patient agreed to inclusion in the database by written consent.
Conflict-of-interest statement: Aggarwal H and Sheffield KM are full-time employees of Eli Lilly and Company and own stock in Eli Lilly and Company. Sorg R and Miksad R are full-time employees of Flatiron Health Inc., an independent subsidiary of the Roche Group. Miksad R and Sorg R report equity ownership in Flatiron Health Inc. (initiated before acquisition by Roche in April 2018). Miksad R, Sorg R, and Lenis D report stock ownership in Roche. At the time of the study, Li L was a full-time employee of Eli Lilly and Company and held stock in Eli Lilly and Company, and Lenis D was a full-time employee of Flatiron Health Inc., an independent subsidiary of the Roche Group. Barzi A has no conflicts of interest to disclose.
Data sharing statement: The data that support the findings of this study have been originated by Flatiron Health, Inc. These de-identified data may be made available upon request, and are subject to a license agreement with Flatiron Health; interested researchers should contact dataaccess@flatiron.com to determine licensing terms. Flatiron Health does not allow sharing of the statistical code for this study.
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.
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: Himani Aggarwal, MPhil, PhD, Research Scientist, Eli Lilly and Company, Lilly Corporate Center, Indianapolis, IN 46225, United States. aggarwal_himani@lilly.com
Received: September 19, 2019
Peer-review started: September 19, 2019
First decision: October 18, 2019
Revised: December 10, 2019
Accepted: December 23, 2019
Article in press: December 23, 2019
Published online: April 15, 2020
Core Tip

Core tip: Primary tumor location is a prognostic factor for metastatic colorectal cancer. Post hoc analyses of randomized clinical trials, including FIRE-3 and CALGB/SWOG 80405, suggest that primary tumor location is also predictive of survival benefit with cetuximab and bevacizumab in metastatic colorectal cancer patients. This analysis of a large cohort of real-world patients with KRAS wild-type metastatic colorectal cancer who received first-line treatment with cetuximab or bevacizumab with 5-fluorouracil-based chemotherapy found a prognostic effect of primary tumor location but not a predictive effect, possibly due to differences between patients in real-world clinical practice vs clinical trial settings.