Letter To The Editor
Copyright ©The Author(s) 2018. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Oncol. Dec 15, 2018; 10(12): 528-531
Published online Dec 15, 2018. doi: 10.4251/wjgo.v10.i12.528
Considering FOLFOXIRI plus bevacizumab for metastatic colorectal cancer with left-sided tumors
Yu Sunakawa, Hironaga Satake, Wataru Ichikawa
Yu Sunakawa, Department of Clinical Oncology, St. Marianna University School of Medicine, Kawasaki, Kanagawa 216-8511, Japan
Hironaga Satake, Cancer Treatment Center, Kansai Medical University Hospital, Hirakata-city, Osaka 573-1191, Japan
Wataru Ichikawa, Division of Medical Oncology, Showa University Fujigaoka Hospital, Yokohama, Kanagawa 227-8501, Japan
Author contributions: Sunakawa Y had full access to the data used in this study, drafted the paper, and had final responsibility for the decision to submit for publication; Sunakawa Y statistically analyzed the data; Satake H and Ichikawa W contributed to analysis and interpretation of the data; all authors contributed to the drafting or revision of the manuscript and have approved the final version.
Conflict-of-interest statement: Sunakawa Y has received honoraria from Taiho Pharmaceutical, Chugai Pharma, Yakult Honsha, Takeda, Merck Serono, Bayer Yakuhin, Eli Lilly Japan, and Sanofi; Satake H has received honoraria from Bayer, Chugai Pharma, Eli Lilly Japan, Merck Serono, Takeda, Taiho Pharmaceutical and Yakult Honsha; Ichikawa W has received honoraria from Chugai Pharma, Merck Serono, Takeda Pharmaceutical, and Taiho Pharmaceutical; research funding from Chugai Pharma, Takeda Pharmaceutical, and Taiho Pharmaceutical.
Open-Access: 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/
Corresponding author to: Yu Sunakawa, MD, PhD, Associate Professor, Department of Clinical Oncology, St. Marianna University School of Medicine, 2-16-1, Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan. y.suna0825@gmail.com
Telephone: +81-44-9778111 Fax: +81-44-9753755
Received: August 27, 2018
Peer-review started: August 27, 2018
First decision: September 11, 2018
Revised: September 17, 2018
Accepted: November 2, 2018
Article in press: November 2, 2018
Published online: December 15, 2018
Processing time: 109 Days and 19.5 Hours
Abstract

A recent subgroup analysis of the TRIBE trial suggested that FOLFOXIRI plus bevacizumab may be a preferred option for the first-line treatment of only right-sided metastatic colorectal cancer (mCRC), regardless of RAS or BRAF status. Our subanalysis of a phase II trial of the FOLFOXIRI triplet regimen plus bevacizumab in patients with mCRC who had RAS mutant tumors showed that tumor shrinkage was better and the duration of treatment was longer in patients with left-sided tumors than in those with right-sided tumors, leading to a higher rate of conversion to surgery in mCRC patients with left-sided tumors. The early and deep responses to the triplet-regimen in patients with left-sided tumors might facilitate conversion treatment resulting in favorable survival. Our data suggest that the FOLFOXIRI plus bevacizumab might be a promising treatment for left-sided mCRC involving RAS mutant tumors.

Keywords: Tumor sidedness; FOLFOXIRI; Bevacizumab; Colorectal cancer; RAS mutation

Core tip: FOLFOXIRI plus bevacizumab regimen might be a preferred option for the first-line treatment of only right-sided metastatic colorectal cancer (mCRC) regardless of RAS or BRAF status. However, subanalysis of a phase II trial of the triplet plus bevacizumab in patients with RAS mutant mCRC demonstrated that more patients with left-sided tumors achieved good tumor shrinkage and long duration of treatment than did patients with right-sided tumors, leading to higher rate of conversion to surgery in mCRC patients with left-sided tumors. Our data suggest that FOLFOXIRI plus bevacizumab may be a promising treatment for left-sided mCRC associated with RAS mutant tumors.