Toxoplasma gondii infection/exposure and the risk of brain tumors: A systematic review and meta-analysis

Ali Abdollahi; Iman Razavian; Elnaz Razavian; Sahar Ghodsian; Mustafa Almukhtar; Elika Marhoommirzabak; Behnam Sartip; Hamid Parsa; Ali Rostami

doi:10.1016/j.canep.2022.102119

Toxoplasma gondii infection/exposure and the risk of brain tumors: A systematic review and meta-analysis

Cancer Epidemiol. 2022 Apr:77:102119. doi: 10.1016/j.canep.2022.102119. Epub 2022 Feb 10.

Authors

Ali Abdollahi¹, Iman Razavian², Elnaz Razavian³, Sahar Ghodsian⁴, Mustafa Almukhtar⁵, Elika Marhoommirzabak⁶, Behnam Sartip⁷, Hamid Parsa⁶, Ali Rostami⁸

Affiliations

¹ Department of Surgery, Faculty of Medicine, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran.
² Department of Neurosurgery, Functional Neurosurgery Research Center, Shohada Tajrish Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
³ Department of Neurology, Tehran Medical Sciences Branch, Islamic Azad University, Tehran, Iran.
⁴ Department of Parasitology and Mycology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
⁵ Independent Researcher, University of Illinois at Chicago Alum, CA, USA.
⁶ Department of Neurology, University of Visayas, Gullas College of Medicine, Cebu City, 600 Cebu, Philippines.
⁷ Department of Internal Medicine, Zanjan University of Medical Sciences, Zanjan, Iran.
⁸ Infectious Diseases and Tropical Medicine Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran. Electronic address: alirostami1984@gmail.com.

PMID: 35152168
DOI: 10.1016/j.canep.2022.102119

Abstract

Background: Brain tumors are among the most fatal cancers with substantial morbidity and mortality worldwide. Epidemiologic evidence suggests that infectious agents, especially, protozoan parasite Toxoplasma gondii could be a possible risk factor or contributor. Here, we performed a systematic review and meta-analysis to evaluate the possible association between T. gondii infection/exposure and risk of brain tumors.

Methods: We searched the PubMed, Embase, Scopus, and Web of Science collection databases from inception through 1st of December 2021. Pooled estimates of odds ratios (ORs) and 95% confidence intervals (CIs) were generated using random effects models. We did the subgroup analysis according to tumor types. Statistical tests for heterogeneity and sensitivity analyses were applied.

Results: A total of seven eligible studies comprising 2323 patients diagnosed with brain tumors and 5131 healthy controls were included in the meta-analysis. T. gondii infection/exposure prevalence was 24.2% (95%CI, 12.7%-41.2) in cases and 12.9% (95%CI, 7.0-22.6%) in control subjects. Pooled analysis showed an overall OR of 1.96 (95%CI, 1.37-2.80), indicating a significant increased risk of brain tumors associated with T. gondii infection/exposure. In subgroup analysis T. gondii infection/exposure was significantly associated with gliomas (OR: 1.64, 95%CI, 1.15-2.33), meningioma (OR: 2.30, 95%CI, 1.0-5.27) and other types of brain tumors (OR: 2.19, 95%CI, 1.02-4.71).

Conclusion: This study provides suggestive evidence for an association between T. gondii infection/exposure and brain tumors. Our findings should be further confirmed by well-designed cohort studies with strict control of confounders. Moreover, we suggest that future studies also focus on the effect of T. gondii infection/exposure to the types of brain tumors.

Keywords: Brain tumors; Glioma; Meningioma; Meta-analysis; Toxoplasma gondii.

Publication types

Meta-Analysis
Review
Systematic Review

MeSH terms

Brain Neoplasms* / epidemiology
Brain Neoplasms* / etiology
Humans
Meningeal Neoplasms*
Risk Factors
Seroepidemiologic Studies
Toxoplasma*
Toxoplasmosis* / complications
Toxoplasmosis* / epidemiology
Toxoplasmosis* / parasitology