Air pollution as a potential risk factor for pancreatic cancer and cholangiocarcinoma in Taiwanese patients

Air pollution is a risk factor for many cancers. However, the effect of air pollution on the risk of pancreatic cancer (PCA) and cholangiocarcinoma (CCA) in Taiwanese patients with remains unclear. This cross-sectional study recruited 370 patients who were tested for serum hepatitis B surface antigen (HBsAg) and hepatitis C virus (anti-HCV) in 2020. The diagnosis of PCA and CCA diagnosis was based on pathology. Daily estimates of air pollutants were aggregated into mean estimates for the previous year based on the date of recruitment or PCA and CCA diagnosis. Out of 370 patients, 16 patients had PCA (4.3%) and 18 patients had CCA (4.9%). The patients with PCA and CCA were older (73.4 years vs. 50.9 years; p < .001) and lived in areas with higher levels of PM_2.5 (19.3 μg/m³ vs. 18.2 μg/m³; p = .03). Logistic regression analysis revealed that the factors associated with PCA and CCA were age (Odds ratio [OR]: 1.09; confidence interval (CI): 1.06–1.13; p < .001) and PM_2.5 (OR: 1.33; CI: 1.00–1.76; p = .05). The best cut-off value for PM_2.5 level associated with PCA and CCA was 18.7 μg/m³ (AUROC, 0.63; p = .01). We defined high level of PM_2.5 as 20 μg/m³. We put PM_2.5 >20 μg/m³ and age >50 years as a covariant and logistic regression analysis revealed that the factors associated with PCA and CCA were age >50 years (OR: 24.77; CI: 3.29–86.10; p = .002) and PM_2.5 >20 μg/m³ (OR: 2.98; CI: 1.30–6.83; p = .01). In this study, we demonstrated that PM_2.5 were associated with PCA and CCA occurrence.