family history and prior allergies of cancers and the risk of adult leukemia in shandong province, china

background: a case-control study was carried out to investigate the roles of prior allergies and family history of cancers and their interaction in the etiology of adult leukemia. methods: prior allergies status and family history of cancers in first-degree relatives were compared between 131 incident leukemia cases and 206 hospital-based controls. odds ratios (or) were estimated using an unconditional regression model taking into account potential confounding factors. results: significant association between adult leukemia and prior allergies and family history of cancer (or=2.09, 95% ci: 1.22-3.58 for prior allergies; and or=2.35, 95% ci: 1.09-5.03 for family history of cancer, or=15.88, 95% ci: 1.77-142.55 for both the two factors (+), respectively) was found after adjusting for potential confounding factors. conclusion: prior allergies and family history of cancers may be risk factors for adult leukemia; their interaction was likely to be synergistic rather than additive for the risk of leukemia.