A study published in JNCI Cancer Spectrum observed an increased risk of prostate cancer, thyroid cancer, and leukemia in 9/11 first responders.
The study included 28,729 members (85.5% male; median age on September 11, 2001, 38 years) of the General Responder Cohort who were enrolled between July 2002 and December 31, 2013. This is a federally funded medical monitoring and treatment program designed to assess responder health and provide treatment for conditions related to the September 11, 2001, exposure.
Researchers assessed cancer registries from New York, New Jersey, Pennsylvania, and Connecticut, as well as Florida and North Carolina, where responders are known to retire. The most common occupations of responders were protective services (49.0%) and construction (20.8%).
Overall increased cancer risk in this population
There were 1,072 cancers in 999 responders, and this population had an overall increased incidence for all cancer sites combined (standardized incidence ratio [SIR], 1.09; 95% CI, 1.02-1.16). Specifically, first responders were at significantly increased risk of prostate cancer (SIR, 1.25; 95% CI, 1.11-1.40), thyroid cancer (SIR, 2.19; 95% CI, 1.71-2.75), and leukemia (SIR, 1.41; 95% CI, 1.01-1.92).
Researchers also observed an increased incidence of esophageal, brain, lung, and colorectal cancers, but these were not statistically significant.
Age of the responder on September 11, 2001, and current smokers had an increased risk for cancers. Cancer incidence was not associated with any World Trade Center exposure index (composite or individual) for all cancer sites combined or for prostate cancer.