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Copyright ©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Meta-Anal. Dec 28, 2021; 9(6): 505-521
Published online Dec 28, 2021. doi: 10.13105/wjma.v9.i6.505
Gastrointestinal tumors and infectious agents: A wide field to explore
Miriam López-Gómez, Belén García de Santiago, Pedro-David Delgado-López, Eduardo Malmierca, Jesús González-Olmedo, César Gómez-Raposo, Carmen Sandoval, Pilar Ruiz-Seco, Nora Escribano, Jorge Francisco Gómez-Cerezo, Enrique Casado
Miriam López-Gómez, Medical Oncology Department. Precision Oncology Laboratory, Infanta Sofía University Hospital, San Sebastián de los Reyes 28231, Madrid, Spain
Belén García de Santiago, Pharmacy Department, Infanta Sofia University Hospital, San Sebastián de los Reyes 28703, Madrid, Spain
Pedro-David Delgado-López, Neurosurgery Department, Burgos University Hospital, Burgos 09006, Spain
Eduardo Malmierca, Pilar Ruiz-Seco, Jorge Francisco Gómez-Cerezo, Internal Medicine Department, Infanta Sofía University Hospital, San Sebastián de los Reyes 28703, Madrid, Spain
Jesús González-Olmedo, César Gómez-Raposo, Carmen Sandoval, Enrique Casado, Medical Oncology Department, Infanta Sofia University Hospital, San Sebastián de los Reyes 28703, Madrid, Spain
Nora Escribano, Intensive Care Unit, Jiménez Díaz Foundation, Madrid 28040, Madrid, Spain
Author contributions: López-Gómez M, García de Santiago B and Delgado-López PD designed and drafted the initial version of the manuscript; Malmierca E reviewed and revised the manuscript for important intellectual content; González-Olmedo J, Gómez-Raposo C, Sandoval C, Ruiz-Seco P, Escribano N and Gómez-Cerezo J made extensive literature review and contributed to the elaboration of different sections; Casado E revised the whole manuscript and provided important suggestions to improve the quality of the paper; All authors have read and approved the final manuscript.
Conflict-of-interest statement: The authors declare no conflict of interest regarding the elaboration of this paper.
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: Miriam López-Gómez, PhD, Doctor, Medical Oncology Department. Precision Oncology Laboratory, Infanta Sofía University Hospital, C/Paseo Europa 34, San Sebastián de los Reyes 28231, Madrid, Spain. miriam.lopez@telefonica.net
Received: May 1, 2021
Peer-review started: May 1, 2021
First decision: July 4, 2021
Revised: August 26, 2021
Accepted: December 23, 2021
Article in press: December 23, 2021
Published online: December 28, 2021
Abstract

Infection is currently one of the main contributors to carcinogenesis. In fact, the International Agency for Research on Cancer has categorized eleven biological agents as group I carcinogens. It is estimated that around 16% of the 12.7 million new cancers diagnosed in 2008 were attributable to infectious agents. Although underdeveloped regions carry the highest incidence rates, about 7.4% of infection-related cancer cases occur in developed areas. Physicians are increasingly aware of the potential carcinogenic role of common virus like the Human Papilloma virus in cervical cancer, or the hepatitis B and C viruses in hepatocarcinoma. However, the carcinogenic role of several other infectious agents is less recognized. Given that gastrointestinal malignancies carry an overall poor prognosis, a better understanding of the carcinogenic mechanisms triggered by infectious agents is key to decrease the rate of cancer related deaths. Preventive measures directed to such infections would ideally impact survival. In this paper we review the main pathogenic mechanisms related to the development of gastrointestinal malignancies induced by infectious microorganisms and other pathogens which are currently under investigation.

Keywords: Gastrointestinal tumors, Infectious agents, Bacteria, Virus, Prevention

Core Tip: Except for pathogens with well-known carcinogenic potential, such as Human Papilloma virus or Hepatitis C virus, physicians are usually unaware of the relationship among other infectious agents and tumors. The identification and subsequent eradication of these pathogens might help to prevent the development of a large number of tumors. Gastrointestinal malignancies are usually related to a very poor outcome. Therefore, detection of carcinogenic pathogens in this population might help to increase overall survival. Screening strategies and further research is required to face with these preventable diseases.