IGF-I and breast cancer: a meta-analysis

Int J Cancer. 2004 Sep 1;111(3):418-23. doi: 10.1002/ijc.20233.


IGFs are peptide hormones involved in the regulation of cell proliferation, differentiation and apoptosis. IGFs are regulated by endocrine and paracrine mechanisms; however, their action in tissue is determined by circulating levels and local production of IGFs and IGF-binding proteins (IGFBPs). Some, but not all, epidemiologic studies have associated high circulating levels of IGF-I with increased risk of breast cancer among premenopausal women. To evaluate the overall association of IGF-I and IGFBP-3 levels with breast cancer risk, we performed a meta-analysis on 16 publications of epidemiologic and clinical studies. Analyses were performed for all women as well as for pre- and postmenopausal women separately. Hedges' standardized mean differences (HSMDs) and odds ratios (ORs) were used to estimate the effect of IGF-I and IGFBP-3. Data analysis showed that circulating levels of IGF-I were not significantly higher in breast cancer patients than in controls for all women and for the postmenopausal group (HSMD = 0.024 and 0.035, respectively; p > 0.40) but were significantly higher (HSMD = 0.170, p < 0.001) for the premenopausal group. ORs for breast cancer risk were 1.05 (95% CI 0.94-1.17), 0.93 (95% CI 0.80-1.10) and 1.39 (95% CI 1.16-1.66). The HSMD of IGFBP-3 was 0.18 (p < 0.001), and the OR for breast cancer was 1.42 (95% CI 1.15-1.74) for premenopausal women. Our results support the suggested association between high IGF-I and IGFBP-3 levels and increased risk of breast cancer in premenopausal women.

Publication types

  • Meta-Analysis

MeSH terms

  • Biomarkers, Tumor / blood*
  • Breast Neoplasms / blood
  • Breast Neoplasms / epidemiology*
  • Female
  • Humans
  • Insulin-Like Growth Factor Binding Protein 3 / blood*
  • Insulin-Like Growth Factor I / analysis*
  • Odds Ratio
  • Premenopause
  • Risk Factors


  • Biomarkers, Tumor
  • Insulin-Like Growth Factor Binding Protein 3
  • Insulin-Like Growth Factor I