Indoor Radon in EGFR- and BRAF-Mutated and ALK-Rearranged Non–Small-Cell Lung Cancer Patients

Radon gas is the leading cause of lung cancer in the nonsmoking population. The World Health Organization (WHO) recommends indoor concentrations of < 100 Bq/m³. Several molecular alterations have been described in non–small-cell lung cancer (NSCLC), mainly in nonsmokers, with no risk factors identified. We studied the role of indoor radon in NSCLC patients harboring specific driver alterations. We assessed the radon concentration from EGFR-, BRAF-mutated (m), and ALK-rearranged (r) NSCLC patients measured by an alpha-track detector placed in their homes between September 2014 and August 2015. Clinical characteristics were collected prospectively, and pathologic samples were reviewed retrospectively. Forty-eight patients were included (36 EGFRm, 10 ALKr, 2 BRAFm). Median radon concentration was 104 Bq/m³ (IQR 69-160) overall, and was 96 Bq/m³ (42-915) for EGFRm, 116 (64-852) for ALKr, and 125 for BRAFm, with no significant differences. Twenty-seven patients (56%) had indoor radon above WHO recommendations, 8 (80%) of 10 ALKr, 2 (100%) of 2 BRAFm, and 17 (47%) of 36 EGFRm. The median indoor radon concentration was above the WHO recommendations, with no differences between EGFR, ALK, and BRAF patients. Concentrations above the WHO recommendations were most common with ALKr and BRAFm. These findings should be validated in larger studies. Radon is the first cause of lung cancer in nonsmokers according to the World Health Organization (WHO), which recommends not exceeding 100Bq/m³ in homes. No risk factor has yet been identified for non–small-cell lung cancer (NSCLC) harboring driver alterations, mainly nonsmokers. We found a median concentration of 104 Bq/m³, above the WHO recommendation in EGFR-mutated, BRAF-mutated, and ALK-rearranged NSCLC patients, with no differences between them.