October 11, 2019 — Current guidelines covering who is eligible for CT lung cancer screening do not take into account the hazards encountered by occupational exposure to environmental toxins, such as those encountered by first responders. That’s according to research presented October 11 at the North American Conference on Lung Cancer in Chicago.
Existing lung cancer guidelines from the U.S. Preventive Services Task Force (USPSTF) focus on individuals who are at high risk of lung cancer due to long histories of smoking. USPSTF recommends screening for people who are ages 55 to 80, have a 30-pack-year history of smoking, and are currently smoking or quit within the last 15 years.
But some 30% of lung cancers are attributable to occupational exposure to carcinogens — and many of those exposed are first responders. Previous research by the U.S. National Institute for Occupational Safety and Health found that first responders have an increased risk of dying from lung cancer that’s 14% higher than the general population.
Indeed, many U.S. fire stations call for lung cancer screening of firefighters using chest radiography every five years. But given that CT has proved to be superior to x-ray for screening — the National Lung Screening Trial found a 20% lower mortality rate for those screened with CT compared with x-ray — shouldn’t first responders be screened with CT instead?
To answer that question, a research team led by Dr. Vershalee Shukla, of the Vincere Cancer Center in Scottsdale, AZ, performed CT lung screening exams of 350 individuals who had worked as first responders for more than 20 years; 195 of the individuals were screened with CT. Of this group, 44.1% or 86 individuals had abnormal findings, which required either surveillance with imaging or further workup with PET/CT or biopsy.
More specifically, the researchers detected 133 pulmonary nodules and five patients with evidence of inhalation injury. The group used the Lung-RADS criteria to determine follow-up even though many of the patients did not meet the age criteria.
“This study demonstrates value for low-dose CT as a screening modality for first responders, who are often diagnosed with lung cancer earlier than smokers for various reasons and, therefore, [were] screened earlier in this study,” Shukla noted in a statement.
She cautioned, however, that the study’s population was small and the research requires additional follow-up. Her group intends to conduct a longer-term study that would involve a low-dose lung CT exam at baseline for every firefighter in Phoenix and then include routine screening starting at age 40. Other screening exams that could be performed could include colonoscopies and upper endoscopies, starting when firefighters are in their early to mid-30s.
“The very early results are promising, and ongoing follow-up will likely lead to further diagnosis of early lung cancer,” the researchers wrote in their study abstract.