Exposure to wildfire smoke may increase the risk of death for lung cancer patients, especially non-smokers, though certain cancer treatments may mitigate this effect, according to a large-scale California study presented at a major medical conference on Saturday.
Researchers followed over 18,000 individuals with non-small cell lung cancer (the most common type) between 2017 and 2020. They found that those residing in areas with the highest levels of wildfire-related air pollution in the year following their cancer diagnosis were more likely to die from the disease.
The study, presented at the American Society of Clinical Oncology meeting in Chicago, revealed that patients who inhaled higher levels of fine particulate matter (PM2.5) – particles with a diameter of 2.5 microns or less that can deeply penetrate the lungs – had a 20% increased risk of dying from lung cancer.
Non-smokers with advanced Stage 4 cancer were particularly vulnerable, with a 55% higher risk of cancer-related death when exposed to high levels of wildfire air pollution.
The study employed advanced modeling techniques to estimate daily air quality at patients’ home addresses, utilizing data from satellites, weather models, smoke forecasts, and air quality monitors.
Interestingly, the researchers also discovered that wildfire smoke exposure did not significantly impact the survival of Stage 4 lung cancer patients with a history of smoking who were treated with immunotherapy.
“This surprising trend suggests that smoke-related changes in the body may interact with certain treatments,” the researchers noted, calling for further investigation into this phenomenon.
Wildfire smoke is known to be more toxic than regular air pollution, containing not only particles of soil and biological materials but also traces of chemicals, metals, plastics, and other synthetic materials.
“As wildfires become more frequent and intense in California and other parts of the U.S., we need targeted health strategies to protect cancer patients and others with serious health problems,” said study leader Dr. Surbhi Singhal of UC Davis Comprehensive Cancer Center in Sacramento, California.