BCG vaccination in childhood could decrease risk of lung cancer

A common tuberculosis (TB) vaccine could decrease the risk of lung cancer if administered during early childhood, according to a study published Sept. 25 in JAMA Network Online.

The study, "Association of Bacille Calmette-Guerin Vaccination in Childhood with Subsequent Cancer," was led by researchers at the Uniformed Services University of the Health Sciences (USU) in collaboration with Walter Reed National Military Medical Center, the University of Pittsburgh, Johns Hopkins University, and Cornell University.

The researchers retrospectively reviewed data from 1935 through 1998, collected from almost 3,000 American Indian and Alaska Native children followed through adulthood – a population in which cancer is the principal cause of premature death, and lung cancer is among the leading causes of death for both men and women combined.

In this study, the children had no previous TB infection and had been vaccinated with a common, low-cost TB vaccine, Bacille Calmette Guerin, or BCG, for the first time around age 8 on average. Of the participants, 1,540 received the BCG vaccine, while 1,423 received a placebo. During a 60-year follow-up, there were 325 reported cases of malignancies, such as leukemia, lymphoma, lung cancer, and breast cancer.

Of all the reported malignancies, the rates were lower but not significantly different among the BCG vaccinated group compared to placebo. However, of the 42 reported cases of lung cancer, the rates were significantly lower in those who received the BCG vaccine, compared to those who received the placebo – receiving the BCG vaccine as a child was associated with 2.5 times lower rates of lung cancer later in life, regardless of smoking and other risk factors.

The researchers also found there were higher rates of cancer among women, overall, but higher rates of lung cancer among men compared to women. Additionally, men who received the BCG vaccine as a child had significantly lower rates of lung cancer, according to Dr. Naomi Aronson, director of USU's Infectious Diseases Division.

This common, low-cost vaccine could potentially help lower the risk of lung cancer in this population, and could also have implication for the general population."

Dr. Naomi Aronson, director, USU's Infectious Diseases Division

Aronson noted that this trial was first executed in 1935 by her grandparents, Joseph and Charlotte Aronson. Not only was it one of the very first placebo-controlled studies in the U.S. at the time, it has also "been in the family" for decades, she said. Aronson's grandfather first learned of the BCG vaccine in France during World War I while assigned with Léon Charles Albert Calmette (the "C" in BCG). At that time, he was deployed as a physician with the American Expeditionary Force.

The study's records were later donated to Johns Hopkins University's Dr. George Comstock, who had worked for Aronson's grandmother when she ran the TB branch for the U.S. Public Health Service in the late 1950s and 1960s. Aronson later helped with the long-term follow-up study, first published in JAMA in 2005 which showed that BCG vaccine protected those immunized from active tuberculosis for at least 60 years. Fast forward to today, this new paper in JAMA Network Online was written by Aronson's nephew, Nicholas Usher, making this endeavor a four-generation family project to date.