Summary: UPDATE – Researchers report that people with a history of chickenpox have about a 21% lower risk of developing glioma, a form of brain cancer. The study’s authors suggest that the biology behind this association deserves further investigation and that, in the future, varicella (chickenpox) vaccination research could inform brain cancer studies.
Having had chickenpox in childhood may be linked to a reduced risk of glioma later in life, according to one of the largest international analyses on this topic.
An international research consortium led by scientists at the Dan L Duncan Comprehensive Cancer Center at Baylor College of Medicine analyzed data from thousands of participants and found an inverse relationship between a history of chickenpox (caused by varicella zoster virus, VZV) and the risk of glioma, a malignant tumor of the brain. The findings were published in the journal Cancer Medicine.
The research team drew on data from the Glioma International Case-Control Study (GICC), a large multisite consortium that collected detailed information on 4,533 glioma cases and 4,171 control participants across five countries. Using rigorous statistical approaches, the investigators estimated the association between prior chickenpox infection and glioma risk while adjusting for potential confounders such as age and sex.
Overall, a reported history of chickenpox was associated with a 21% lower risk of glioma (adjusted estimate with 95% confidence interval indicating a statistically significant inverse association). The protective association appeared stronger for high-grade gliomas, suggesting the relationship may vary by tumor aggressiveness.
Lead investigators on the study include Dr. Melissa Bondy, associate director for cancer prevention and population sciences and a McNair Scholar at Baylor, and Dr. E. Susan Amirian, assistant professor in the Duncan Cancer Center at Baylor. The consortium’s analysis supports earlier, smaller studies that observed a similar inverse link between varicella infection and glioma risk, lending weight to the hypothesis that this association is unlikely to be due to chance alone.
While the study does not establish a direct causal mechanism, the authors emphasize the need for follow-up research to explore possible biological explanations. Varicella zoster virus is a neurotropic alpha-herpesvirus that establishes lifelong latency in nerve ganglia after an initial chickenpox infection. How prior VZV infection might confer long-term alterations in immune surveillance, viral-host interactions, or other pathways relevant to glioma development remains an open question. Future work could include laboratory studies, longitudinal cohorts, and meta-analyses to clarify mechanisms and assess whether varicella vaccination has any implications for brain cancer risk or prevention research.
The GICC report lists many collaborators across institutions, including investigators from Baylor College of Medicine; the University of California; the Mayo Clinic Comprehensive Cancer Center; Memorial Sloan Kettering Cancer Center; Yale University School of Medicine and Brigham and Women’s Hospital; Case Western Reserve University School of Medicine; Duke University Medical Center; the Gertner Institute and Tel-Aviv University; NorthShore University HealthSystem; the University of Alberta; the University of Southern California Keck School of Medicine; The University of Texas MD Anderson Cancer Center; Norris Cotton Cancer Center; and Umeå University. Key contributors include E. Susan Amirian, Michael E. Scheurer, Renke Zhou, Margaret R. Wrensch, Georgina N. Armstrong, Daniel Lachance, Sara H. Olson, Ching C. Lau, Elizabeth B. Claus, Jill S. Barnholtz-Sloan, Dora Il’yasova, Joellen Schildkraut, Francis Ali-Osman, Siegal Sadetzki, Robert B. Jenkins, Jonine L. Bernstein, Ryan T. Merrell, Faith G. Davis, Rose Lai, Sanjay Shete, Christopher I. Amos, Beatrice S. Melin, and Melissa L. Bondy.
Funding Funding for the study was provided in part by the National Cancer Institute through several grants supporting cancer research infrastructure and investigator efforts.
Source: Graciela Gutierrez – Baylor College of Medicine
Image credit: Nevit Dilmen (image used for illustrative purposes).
Original research: The study, titled “History of chickenpox in glioma risk: a report from the Glioma International Case–Control Study (GICC),” was published in Cancer Medicine (online March 13, 2016) and reports on the association between varicella history and glioma risk based on the GICC data set.
Abstract (summary)
Varicella zoster virus (VZV) is a neurotropic alpha-herpesvirus that causes chickenpox and then remains latent in cranial nerve and dorsal root ganglia. Prior studies have consistently reported an inverse association between a history of chickenpox and the risk of glioma. In this large multisite analysis using GICC data from 4,533 cases and 4,171 controls, a positive history of chickenpox was associated with a 21% lower overall glioma risk after adjusting for age and sex. The protective association was more pronounced for high-grade gliomas. These results strengthen the evidence that the observed protective link is unlikely to be coincidental and underscore the need for additional research, including meta-analyses and mechanistic studies, to explore potential biological explanations for the relationship.