Medical history, lifestyle, family history, and occupational risk factors for adult acute lymphocytic leukemia: The InterLymph Non-Hodgkin Lymphoma subtypes project

Background: Acute lymphoblastic leukemia/lymphoma (ALL) in adults is a rare malignancy with a poor clinical outcome, and few reported etiologic risk factors. Methods: We performed an exploratory pooled study of 152 ALL cases and 23 096 controls from 16 case-control studies to investigate the role of medical history, lifestyle, family history, and occupational risk factors and risk of ALL. Agerace/ethnicity-, sex-, and study-adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using logistic regression. Results: An increased risk of ALL was found in those with a family history of a hematological malignancy (OR = 2.6, 95% CI = 1.22 to 5.54) and in leather (OR = 3.91, 95% CI = 1.35 to 11.35) and sewing/embroidery workers (OR = 2.92, 95% CI = 1.00 to 8.49). Consumers of alcohol had an increased risk of B-cell ALL (OR = 2.87, 95% CI = 1.18 to 6.95). Conclusions: The small number of statistically significant risk factors identified out of the 112 variables examined could be chance findings and will require further replication to assess their role in the etiology of adult ALL.