Fine Particulate Matter Air Pollution and Mortality among Pediatric, Adolescent, and Young Adult Cancer Patients

Background: Air pollution is a carcinogen and causes pulmonary and cardiac complications. We examined the association of fine particulate matter pollution (PM2.5) and mortality from cancer and all causes among pediatric, adolescent, and young adult (AYA) patients with cancer in Utah, a state with considerable variation in PM2.5. Methods: We followed 2,444 pediatric (diagnosed ages 0–14) and 13,459 AYA (diagnosed ages 15–39) patients diagnosed in 1986–2015 from diagnosis to 5 and 10 years postdiagnosis, death, or emigration. We measured average monthly PM2.5 by ZIP code during follow-up. Separate pediatric and AYA multivariable Cox models estimated the association of PM2.5 and mortality. Among AYAs, we examined effect modification of PM2.5 and mortality by stage while controlling for cancer type. Results: Increases in PM2.5 per 5 μg/m3 were associated with cancer mortality in pediatric lymphomas and central nervous system (CNS) tumors at both time points, and all cause mortality in lymphoid leukemias [HR5-year = 1.32 (1.02–1.71)]. Among AYAs, PM2.5 per 5 μg/m3 was associated with cancer mortality in CNS tumors and carcinomas at both time points, and all cause mortality for all AYA cancer types [HR5-year = 1.06 (1.01–1.13)]. PM2.5 ≥12 μg/m3 was associated with cancer mortality among breast [HR5-year = 1.50 (1.29–1.74); HR10-year = 1.30 (1.13–1.50)] and colorectal cancers [HR5-year = 1.74 (1.29–2.35); HR10-year = 1.67 (1.20–2.31)] at both time points. Effect modification by stage was significant, with local tumors at highest risk. Conclusions: PM2.5 was associated with mortality in pediatric and AYA patients with specific cancers. Impact: Limiting PM2.5 exposure may be important for young cancer patients with certain cancers. See all articles in this CEBP Focus section, “Environmental Carcinogenesis: Pathways to Prevention.”