1577P - Indoor radon in patients with lung cancer in Spain: Preliminary data from the MIRROR study

Background

Indoor radon (Rn) is one of the leading causes of lung cancer (LC) in non-smokers, and the 2^nd one in smokers. However, it remains unknown in Spain. We studied indoor Rn in a large cohort of patients (pts) with non-small cell LC (NSCLC) in Spain.

Methods

Prospective multicentric study of pts with NSCLC enrolled in 12 hospitals (6 regions) in Spain from Jan. 2021 to date. Each pt received 1 or 2 alpha-track detectors to measure Rn for ≥3 months in their home, and a detailed questionnaire, with demographics, smoking, other exposures, etc. Clinical/Tumor data were prospectively collected and optional tissue sample for translational research.

Results

Out of 613 pts enrolled to date, we report here data of 209: 58,8% male, 77,2% smokers, with median age of 64; 72 (34,4%) with primary school education. One third had advanced stage. Adenocarcinoma was the predominant histology (83,2%). Molecular profile was known for 190 (90,1%) being EGFR the most common alteration (13,8%). Most of pts lived in flat (68%), followed by detached house (25%); 24% lived in basement, ground floor; 64,1% living there ≥ 20 years. Before participating in this study, most of the pts (55.6%) were not aware of Rn. Among those who were familiar with Rn, television was the main source of information (40.8%), followed by school (29%). After the study, 88.9% request more information about Rn. Overall, the media Rn was 36 Bq/m³ (10-600); higher Rn was observed in ground floor (75 vs. 34 Bq/m³ in the rest, p=0.012). Forty-two pts (20.1%) had Rn ≥100Bq/m³ and 15 (7.2%) ≥ 200Bq/m³. Highest Rn was observed in Galicia, with median of 156 Bq/m³, vs. Catalonia, with 17 Bq/m³ (p<0.001). Among pts living in their homes for ≥ 20y (n=142), the median Rn was 34 Bq/m³ (10-600). Higher Rn was observed in ground floors (55.6% of those with ≥200 Bq/m³). 25 pts (17.6%) had Rn median ≥100 Bq/m³, 8 (5.6%) ≥200 Bq/m³. In this preliminary cohort, no differences were observed in Rn levels (median) by sex, smoking habits or histology.

Conclusions

Most pts in this study were unaware of Rn, a prevalent risk factor for LC in Spain. The measurement of indoor Rn is feasible, with 20.1% of pts homes with ≥100Bq/m³ and 7.2% ≥200 Bq/m³, providing valuable data for cancer prevention. This study is still ongoing to study the Rn-associated profile in a larger cohort of pts.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Project FIS PI21/01653, funded by Instituto de Salud Carlos III (ISCIII) and co-funded by the European Union.

Disclosure

M. Garcia De Herreros: Financial Interests, Personal, Invited Speaker: NOVARTIS, IPSEN. H. Arasanz: Financial Interests, Personal, Invited Speaker: Takeda; Financial Interests, Personal, Advisory Board: AstraZeneca; Financial Interests, Personal, Other, Clinical Trial coordination: Ferrer Farma; Financial Interests, Personal, Other, Travelling/accommodation expenses: Angelini, BMS, MSD, Roche, Takeda. S. Vazquez Estevez: Financial Interests, Personal, Advisory Board: BMS. S. Catort Tort: Financial Interests, Personal, Advisory Board: AstraZeneca, Roche, Pfizer. L.A. Leon Mateos: Financial Interests, Personal, Advisory Board: AstraZeneca, Pfizer, Bristol, Merck, Amgen, Takeda, Janssen. C. Teixido: Financial Interests, Personal, Invited Speaker: AstraZeneca, Merck Sharp & Dohme, Roche Farma, Diaceutics, Pfizer; Financial Interests, Personal, Advisory Board: AstraZeneca, Novartis; Financial Interests, Institutional, Research Grant: Novartis, AstraZeneca. R. López Castro: Financial Interests, Personal, Advisory Board: AstraZeneca, Roche, Novartis, Amgen, Pierre Fabre. L. Mezquita: Financial Interests, Personal, Advisory Board: Takeda, Roche, AstraZeneca, MSD, Janssen; Financial Interests, Personal, Invited Speaker: Takeda, Roche, BMS, AstraZeneca, Janssen; Financial Interests, Personal, Research Grant, SEOM Beca Retorno 2019: BI; Financial Interests, Personal, Research Grant, ESMO TR Research Fellowship 2019: BMS; Financial Interests, Institutional, Research Grant, COVID research Grant: Amgen; Financial Interests, Institutional, Coordinating PI, Cover cost of molecular test: Inivata; Financial Interests, Institutional, Coordinating PI: GILEAD; Financial Interests, Institutional, Coordinating PI, Beca SEOM Grupo Emergente 2022: AstraZeneca. All other authors have declared no conflicts of interest.