1. ¹Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA
2. ²Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
3. ³Department of Epidemiology, Harvard School of Public Health, Boston, MA, USA
4. ⁴Department of Nutrition, Harvard School of Public Health, Boston, MA, USA
5. ⁵Channing Laboratory, Department of Medicine, Brigham and Women's Hospital, and Harvard Medical School, Boston, MA, USA
6. ⁶Ludwig Boltzmann-Institute for Applied Cancer Research, KFJ-Spital, Vienna, Austria and Applied Cancer Research – Institute for Translational Research Vienna (ACR–ITR VIEnna), Vienna, Austria
7. ⁷Division of Preventive Medicine, Brigham and Women's Hospital, Boston, MA, USA
8. ⁸Division of Public Health Sciences, University of Washington School of Nursing, Seattle, WA, USA
9. ⁹Department of Epidemiology and Population Health, Albert Einstein College of Medicine, Bronx, NY, USA
10. ¹⁰Department of Medicine and Oncology, Jewish General Hospital and McGill University, Montreal, Quebec, Canada

Correspondence: Dr BM Wolpin, Dana-Farber Cancer Institute, 44 Binney street, Boston, MA 02115, USA. E-mail: bwolpin@partners.org

Received 1 February 2007; Revised 13 April 2007; Accepted 9 May 2007; Published online 29 May 2007.

Abstract

Insulin-like growth factor (IGF)-I induces growth in pancreatic cancer cells and blockade of the IGF-I receptor has antitumour activity. The association of plasma IGF-I and IGF binding protein-3 (IGFBP-3) with pancreatic cancer risk has been investigated in two small studies, with conflicting results. We conducted a nested case–control study within four large, prospective cohorts to investigate whether prediagnostic plasma levels of IGF-I, IGF-II, and IGFBP-3 were associated with pancreatic cancer risk. Plasma levels in 212 cases and 635 matched controls were compared by conditional logistic regression, with adjustment for other known pancreatic cancer risk factors. No association was observed between plasma levels of IGF-I, IGF-II, or IGFBP-3 and incident diagnosis of pancreatic cancer. Relative risks for the highest vs the lowest quartile of IGF-I, IGF-II, and IGFBP-3 were 0.94 (95% confidence interval (CI), 0.60–1.48), 0.96 (95% CI, 0.61–1.52), and 1.21 (95% CI, 0.75–1.92), respectively. The relative risk for the molar ratio of IGF-I and IGFBP-3, a surrogate measure for free IGF-I, was 0.84 (95% CI, 0.54–1.31). Additionally, no association was noted in stratified analyses or when requiring longer follow-up. In four prospective cohorts, we found no association between the risk of pancreatic cancer and prediagnostic plasma levels of IGF-I, IGF-II, or IGFBP-3.