Can BCG Vaccination During Childhood Reduce the Risk of Subsequent Lung Cancer?
Posted: Monday, December 2, 2019
Childhood Mycobacterium bovis BCG vaccination appears to be linked to a lower risk of subsequent lung cancer development in American Indian and Alaska Native groups, according to a 60-year follow-up of a clinical trial published in JAMA Network Open. Naomi E. Aronson, MD, of the Uniformed Services University of the Health Sciences, Maryland, and colleagues suggest the results may have broad implications due to lung cancer’s high mortality rate, and further study cohorts are necessary to corroborate their findings.
“In this analysis, BCG vaccine recipients had a significantly lower risk of lung cancer than placebo recipients [when] controlling for sex, region, alcohol overuse, smoking status, and tuberculosis,” the authors concluded.
The authors followed patients 60 years after they participated in a clinical trial wherein they were assigned to the vaccine group systematically and then randomly assigned by alternation. Between 1935 and 1998, a total of 2,963 American Indian and Alaska Native schoolchildren younger than age 20 from nine sites in five U.S. states were enrolled in the study. The patients did not have previous tuberculosis infection. They received either BCG vaccine (n = 1,540) or saline placebo (n = 1,423). Patient data such as smoking history and demographics were collected.
In both groups at the time of follow-up, 7% could not be located. The mortality rate at follow-up was 44% in the placebo group and 41% in the BCG vaccine group. Although the overall rate of cancer diagnosis was not different between the groups (hazard ratio = 0.82), the rate of lung cancer was significantly lower in the BCG vaccine group than in the placebo group (18.2 vs. 45.4 cases per 100,000 person-years; hazard ratio = 0.38).
Disclosure: The study authors’ disclosure information can be found at jamanetwork.com.