Abstract 1437: Ambient air pollution and risk of prostate cancer: The multiethnic cohort study
Authors: Wang Anqi , Tseng Chiu-chen , Rose Heather , Cheng Iona , Wu Anna H. , Haiman Christopher A. 
Published: June 2022

Previous epidemiological evidence on air pollution and prostate cancer risk is limited, with few studies examining the time varying effects of air-pollution, and primarily among whites in the US and Canada. To further our understanding on this topic, we assessed ambient air pollutants in relation to prostate cancer incidence in a large multi-ethnic population. We included 33,830 men aged 45 years or older at baseline (1993-1996) who resided in Southern California at enrollment in the Multiethnic Cohort (24.5% African American, 15.1% Japanese American, 48.4% Latino, 0.2% Native Hawaiian, and 11.8% White). Until 2016, with a median of 20 years of follow-up, 4,540 prostate cancer cases were identified by linkage to the California SEER cancer registry. Monthly exposures to particulate matter with aerodynamic diameter ≤ 10 μm (PM10) and nitrogen oxides (NOx) per participant were estimated by Kriging interpolation based on air-monitoring data and residential addresses. We used Cox proportional hazards models to estimate the association between time-varying air-pollutant levels and prostate cancer risk, using age in months as the time metric. We adjusted for neighborhood socioeconomic status (nSES) at baseline and current nSES at event, education, race/ethnicity, smoking pack years, BMI, diabetes status, asthma history, and family history of prostate cancer, using age at cohort entry as the strata variable. The average NOx and PM10 over the study period was 73.1 parts per billion (ppb) and 38.1 μg/m3 in prostate cancer cases, respectively, and 60.9 ppb and 35.5 μg/m3 in men without prostate cancer, respectively. Across racial/ethnic groups, African Americans had the highest average NOx levels (74.3ppb) and Latinos had the highest average PM10 levels (39.0 μg/m3) over the study period. In the overall population, NOx per 50 ppb was statistically significantly associated with an increased risk of prostate cancer [hazard ratio (HR)=1.12, 95% confidence interval (CI): 1.01-1.25] and PM10 per 10 μg/m3 was associated with a suggestive increased risk (HR=1.07, 95%CI: 0.99-1.16). In analysis by race/ethnicity, statistically significant positive associations with NOx (HR=1.25, 95%CI: 1.07-1.46) and PM10 (HR=1.21, 95%CI: 1.07-1.38) were detected among African American, but not consistently in other racial/ethnic groups. In a subset of 21,537 men with no residential moves over the follow-up period, we observed positive associations for both NOx and PM10 similar to those among all men. In conclusion, our results suggest that both NOx and PM10 are associated with an increased risk of prostate cancer. Analyses of other air pollutants in relation to prostate cancer risk and disease aggressiveness are ongoing.

Citation Format: Anqi Wang, Chiu-chen Tseng, Heather Rose, Iona Cheng, Anna H. Wu, Christopher A. Haiman. Ambient air pollution and risk of prostate cancer: The multiethnic cohort study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1437.