Positive Health Online

Abstract

DOUGLAS and COLLEAGUES, Nutritional Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, Department of Health and Human Services, Rockville, Maryland, USA conducted two nested, case-control studies in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study (ATBC) and Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO) to test whether prediagnostic circulating C-reactive protein (CRP) concentrations were associated with pancreatic adenocarcinoma.

Background

Many epidemiologic studies have examined the association between C-reactive protein (CRP) and risk of cancer with inconsistent results.

Methodology

We conducted two nested, case-control studies in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study (ATBC) and Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO) to test whether prediagnostic circulating CRP concentrations were associated with pancreatic adenocarcinoma. Between 1985 and 2004, 311 cases occurred in ATBC and between 1994 and 2006, 182 cases occurred in PLCO. Controls (n = 510 in ATBC, n = 374 in PLCO) were alive at the time the case was diagnosed and were matched by age, date of blood draw, sex, and race. We used conditional logistic regression adjusted for smoking to calculate OR and 95% CI for pancreatic cancer.

Results

CRP concentrations (ng/mL) tended to be inversely or not associated with pancreatic cancer risk in ATBC, PLCO, and combined analyses [per standardized quintile increase in CRP, continuous OR = 0.94 (95% CI, 0.89-0.99), OR = 0.99 (95% CI, 0.95-1.04), OR = 0.98 (95% CI, 0.95-1.01), respectively]. In combined analyses, we observed a significant interaction (P(interaction) = 0.02) such that inverse associations were suggestive in younger (OR = 0.95; 95% CI, 0.90-1.01), but not older, participants.

Conclusion

Our results do not support the hypothesis that higher CRP concentrations are associated with incident pancreatic cancer. Impact: Our results highlight the importance of investigating more specific biomarkers for inflammation that may reflect the biological mechanisms underlying pancreatic cancer in prospective cohort studies.

References

Douglas JB, Silverman DT, Weinstein SJ, Graubard BI, Pollak MN, Tao Y, Virtamo J, Albanes D and Stolzenberg-Solomon RZ. Serum C-reactive protein and risk of pancreatic cancer in two nested, case-control studies. Source Cancer Epidemiology, Biomarkers & Prevention. 20(2):359-69. Feb 2011.