González-Montero J, Valenzuela G, Rojas CI, Burotto M. Sidedness matters: Colon cancer outcomes in low-resource settings. World J Clin Oncol 2025; 16(10): 108937 [DOI: 10.5306/wjco.v16.i10.108937]
Corresponding Author of This Article
Jaime González-Montero, MD, PhD, Assistant Professor, Department of Oncology, Bradford Hill Clinical Research Center, Palestina 343, Fifth Floor, Recoleta, Santiago 8420383, Chile. jagonzalez@ug.uchile.cl
Research Domain of This Article
Oncology
Article-Type of This Article
Minireviews
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 Clin Oncol. Oct 24, 2025; 16(10): 108937 Published online Oct 24, 2025. doi: 10.5306/wjco.v16.i10.108937
Sidedness matters: Colon cancer outcomes in low-resource settings
Jaime González-Montero, Guillermo Valenzuela, Carlos I Rojas, Mauricio Burotto
Jaime González-Montero, Carlos I Rojas, Mauricio Burotto, Department of Oncology, Bradford Hill Clinical Research Center, Santiago 8420383, Chile
Guillermo Valenzuela, Faculty of Medicine, University of Chile, Santiago 8380453, Chile
Author contributions: González-Montero J conceived the review, defined the scope and methodology, and supervised the project; Valenzuela G performed the literature search and screening, extracted/curated data, and drafted the initial sections; Rojas CI synthesized the evidence, prepared the tables/figures, and contributed to the writing; Burotto M provided senior clinical oversight and critical revision for important intellectual content; and all authors contributed to interpretation, revised the manuscript, and approved the final version.
Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article.
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: Jaime González-Montero, MD, PhD, Assistant Professor, Department of Oncology, Bradford Hill Clinical Research Center, Palestina 343, Fifth Floor, Recoleta, Santiago 8420383, Chile. jagonzalez@ug.uchile.cl
Received: April 27, 2025 Revised: May 27, 2025 Accepted: September 8, 2025 Published online: October 24, 2025 Processing time: 181 Days and 16.2 Hours
Core Tip
Core Tip: Colon tumor sidedness is a practical compass for determining treatment. This review synthesizes epidemiologic, molecular, and clinical differences between right-sided colon cancer (RCC) and left-sided colon cancer (LCC). Older patients with RCC more frequently exhibit microsatellite instability-high status/deficient mismatch repair (MMR), Kirsten rat sarcoma viral oncogene homolog/v-raf murine sarcoma viral oncogene homolog B1 mutations, poorer prognosis in metastatic disease, and limited benefit from anti-epidermal growth factor receptor (EGFR). LCC is more often RAS/v-raf murine sarcoma viral oncogene homolog B1 wild-type and EGFR-responsive. We propose a low-resource plan: Prioritize MMR immunohistochemistry; consider immunotherapy for deficient MMR/microsatellite instability-high; use 5-fluorouracil + leucovorin + oxaliplatin + irinotecan ± anti-angiogenic agents for RCC and doublet ± anti-angiogenic therapy for LCC; restrict anti-EGFR to confirmed wild-type disease.
