Pre- and Postnatal Exposures to Tobacco Smoking and Survival of Childhood Acute Lymphoblastic and Myeloid Leukemias in California, United States.

BACKGROUND: Tobacco smoke adversely affects the prognosis of adult cancers including myeloid leukemia, but less is known in children. METHODS: We evaluated whether pre- and postnatal exposures to tobacco smoke decrease 5-year survival of 1,235 childhood acute lymphoblastic leukemia (ALL) and 188 childhood acute myeloid leukemia (AML) cases derived from a population-based case-control study in California. Cases were diagnosed between 1995 and 2015 (median follow-up time of 13.2 years overall). We obtained data on tobacco smoking (before conception, during pregnancy, after birth), parental education and income, clinical features, and vital status through 2020. Cox proportional hazards regression was used to calculate hazard ratios (HR) and 95% confidence intervals (CI) for mortality associated with smoking, adjusting for sociodemographic characteristics and risk group (ALL only). RESULTS: About 23% of mothers and 39% of fathers reported smoking and 130 children with ALL and 52 with AML died within 5 years. For AML, increased risks of death were observed among children whose fathers smoked before conception compared with nonsmoking fathers [HR = 1.41; 95% confidence interval (CI), 0.95-3.44 and 3.47; 95% CI, 1.37-8.81, respectively for <20 vs. ≥20 cigarettes per day; Ptrend = 0.01]. HR for child's passive smoking was 1.74, 95% CI, 0.81-3.73. Paternal preconception smoking may also reduce 5-year survival among ALL with favorable prognostic molecular subtypes (high hyperdiploidy and absence of IKZF1 gene deletion), although the associations did not reach statistical significance (Pheterogeneity = 0.07). CONCLUSIONS: Paternal preconception smoking decreased 5-year survival of childhood AML. IMPACT: Knowledge of exposure to tobacco smoking should be integrated in the treatment plan of childhood leukemias.

Disparities in household material hardship, financial toxicity, and income loss in pediatric cancer.

BACKGROUND: Based on previous reports of disparities in financial burden following a cancer diagnosis, this study aims to characterize mechanisms of disparities experienced by caregivers of children with cancer, including the impact of work flexibility and social support. METHODS: Cross-sectional survey (in English or Spanish) of caregivers of children with cancer that assessed household material hardship (HMH), financial toxicity, and income change. RESULTS: Of 156 caregivers surveyed, 32% were Hispanic and 32% were low income. Hispanic caregivers were more likely to report HMH and financial toxicity compared to non-Hispanic White and Asian (HMH: 57% vs. 21% vs. 19%, p < .001; financial toxicity: 73% vs. 52% vs. 53%, p = .07). Low- and middle-income caregivers were more likely to experience HMH and financial toxicity compared to high-income caregivers (HMH: 68% low vs. 38% middle vs. 8.7% high, p < .001; financial toxicity: 81% vs. 68% vs. 44%, p < .001). All income categories demonstrated significant increases in HMH 1 year after diagnosis. Seventeen percent reported more than 40% income loss, more of whom were low income than high income (27% vs. 12%, p = .20). Work flexibility and social support were associated with income and financial toxicity. CONCLUSION: HMH, financial toxicity, and income loss are prevalent after a child's cancer diagnosis, suggesting that screening should be incorporated into routine care. This financial burden disproportionately affects low-income and Hispanic caregivers. Further research is needed to elucidate the roles of work flexibility and social support, how safety net services are utilized by families, and how best to support families with HMH.