Abstract 4162: Circulating C-reactive protein and lung cancer risk: A nested case-control study in the Southern Community Cohort Study

Abstract

Abstract Lung cancer is the leading cause of cancer deaths in the United States and many other countries. Cumulative evidence suggests that chronic inflammation may play an etiologic role in lung carcinogenesis. C-reactive protein (CRP), a circulating biomarker of systemic inflammation, has been associated with increased lung cancer risk in several retrospective and a few prospective studies. However, prior studies included only a small number of African Americans with lung cancer, a group with higher lung cancer incidence rates than other ethnic or racial groups. We conducted a nested case-control study to evaluate the association of pre-diagnostic circulating levels of CRP with subsequent risk of lung cancer using data and biological samples collected in the Southern Community Cohort Study (SCCS), a prospective cohort study, in which approximately 86,000 men and women aged 40-79 years, two-thirds of whom are African American, were recruited from 2002 to 2009. Plasma CRP levels in 396 incident lung cancer cases (258 African Americans and 130 Whites) were compared with 784 matched controls. Overall, baseline plasma CRP levels were 29.4% higher among participants who subsequently developed lung cancer than among those who remained free of the disease (geometric mean: 4.4 µg/ml vs. 3.4 µg/ml; P = 0.0015). This difference was seen primarily among African Americans (geometric mean: 4.1 µg/ml vs. 3.0 µg/ml; P=0.0026) and not among Whites (geometric mean: 5.0 µg/ml vs. 4.5 µg/ml; P=0.3613). In both African Americans and Whites, elevated risk of lung cancer was associated with high circulating levels of CRP. However, the association was only statistically significant among African Americans; adjusted odds ratios (ORs) for developing lung cancer increased from 1.0 to 1.46 (95%CI: 0.89-2.40); 1.52 (95%CI: 0.88-2.61), and 2.95 (95%CI: 1.77-4.93) with increasing quartiles of plasma CRP (P-trend = 0.0018). The findings from this study suggest that circulating CRP level is positively associated with prospective lung cancer risk among African Americans. Citation Format: Jie Wu, Wei Zheng, Wanqing Wen, Margaret K. Hargreaves, William J. Blot, Qiuyin Cai. Circulating C-reactive protein and lung cancer risk: A nested case-control study in the Southern Community Cohort Study. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4162. doi:10.1158/1538-7445.AM2014-4162