Insulin and Related Factors in Premenopausal Breast Cancer Risk

Breast Cancer Res Treat. 1998 Jan;47(2):111-20. doi: 10.1023/a:1005831013718.

Abstract

Background: Insulin and insulin-like growth factor I (IGF-I) are important mitogens in vitro and in vivo. It has been hypothesized that these factors may play an important role in the development of breast cancer.

Methods: A case-control study comparing plasma insulin levels in 99 premenopausal women with newly diagnosed node-negative invasive carcinoma of the breast and 99 age-matched controls with incident biopsied non-proliferative breast disease (NP) was conducted. Women with known diabetes were excluded.

Results: For the entire study group, mean age was 42.6 +/- 5.1 years and mean weight was 62.9 +/- 10.3 kg. After adjustment for age and weight, elevated insulin levels were significantly associated with breast cancer, Odds Ratio (OR) for women in the highest insulin quintile versus the lowest quintile = 2.83 (95% Confidence Interval [CI] 1.22-6.58). There were no statistically significant differences between cases and controls for IGF-I and IGFBP-1 levels. However, after adjustment for age, the association between plasma levels of insulin-like growth factor binding protein 3 (IGFBP-3) and breast cancer approached statistical significance; OR for highest quintile versus lowest quintile of IGFBP-3 being 2.05 (95% CI, 0.93-4.53). All results were independent of diet and other known risk factors for breast cancer.

Conclusion: Circulating insulin levels and possibly IGFBP-3 levels are elevated in women with premenopausal breast cancer. This association may reflect an underlying syndrome of insulin resistance that is independent of obesity.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Breast Neoplasms / blood*
  • Female
  • Humans
  • Insulin / blood*
  • Insulin Resistance
  • Insulin-Like Growth Factor Binding Proteins / blood
  • Insulin-Like Growth Factor I / metabolism
  • Premenopause / blood
  • Risk Factors

Substances

  • Insulin
  • Insulin-Like Growth Factor Binding Proteins
  • Insulin-Like Growth Factor I