Abstract A67: Differences in the cancer burden for foreign-born versus U.S.-born Arab Americans living in metropolitan Detroit.

Introduction: Metropolitan Detroit is home to one of the largest populations of Arabs outside of the Middle East. However, cancer statistics for this population group are not available because Arab-Americans (ArA) are not considered a minority group by the federal government. Because of this limitation, little is known about the cancer burden among Arab Americans; furthermore there is no information on cancer by nativity status, which can often provide important clues to environmental factors in cancer etiology. Methods: We developed validated name lists as well as a methodology using Social Security Numbers to identify cancer cases of probable Arab ancestry by nativity status found in the Metropolitan Detroit Cancer Surveillance System database. ArA cancer cases diagnosed between the years of 1990-2009 were identified and compared to non-Hispanic white (NHW) cases using age-standardized proportional incidence ratios (PIRs) and 95% confidence intervals. PIRs were also calculated by country of origin (US-born versus foreign-born) for ArA. Results: A total of 9,327 Arab American cases were identified (4,463 men and 4,684 women). 46% of the ArA cases were born outside the United States. Compared to NHW, ArA men had a higher proportion of multiple myeloma, leukemia, kidney, liver, and bladder cancer. While the proportion of bladder cancer remained significantly higher among ArA men regardless of nativity status, ArA immigrants had a higher proportion of multiple myeloma, kidney, liver, and stomach cancer, while US-born ArA did not. ArA women had a higher proportion of lymphoma, leukemia, breast, gallbladder, liver, stomach, and thyroid cancer compared to NHW. This pattern remained for both foreign-born and US-born ArA females, except that female ArA immigrants had a higher proportion of breast and stomach cancer while US- born females did not. Conclusions: As expected, cancers such as liver and stomach, which can be related to infectious causes and have a relatively high incidence in developing countries, are seen proportionally higher in the foreign-born ArA than US-born ArA as compared to NHW. However, there are other patterns that deserve further investigation. An intriguing finding was foreign-born ArA women had proportionally higher breast cancer incidence while US-born ArA women did not when compared to NHW, a pattern that is opposite in other immigrant groups. We also are interested in the higher proportion of bladder cancer in ArA men regardless of nativity. The prevalence of this cancer is high in some Arab countries and is related to an infectious cause. However, the bladder cancer seen in the U.S. is of a different histological type (transitional cell), a type that is associated with the risk factor smoking. Although smoking prevalence among ArA men is uncertain, other smoking related cancers are not over-represented proportionally, which invites etiologic questions about bladder cancer risk factors in ArA men. Citation Format: Kendra Schwartz, Julie J. Ruterbusch, Fatima Khan. Differences in the cancer burden for foreign-born versus U.S.-born Arab Americans living in metropolitan Detroit. [abstract]. In: Proceedings of the Fifth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2012 Oct 27-30; San Diego, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2012;21(10 Suppl):Abstract nr A67.