Obesity-related inflammation predisposes Asian women to breast cancer
A subclinical inflammatory state resulting from increased adiposity and metabolic dysfunction appears to contribute to breast cancer pathogenesis in Asian women, a Taiwan study has found.
Researchers looked at 72 breast cancer patients (median age, 51; median body mass index [BMI], 23.2 kg/m2) who underwent mastectomy. All patients contributed breast white adipose tissue (WAT) and fasting blood samples, while body composition was measured in a subgroup using bioelectrical impedance analysis. WAT inflammation was defined by the presence of crown-like structures of the breast, which are composed of dead or dying adipocytes surrounded by macrophages.
Of the patients, 31 (43 percent) presented with breast WAT, which was associated with higher BMI (p<0.01), elevated levels of body fat (p<0.01), C-reactive protein (p=0.02), triglycerides (p<0.01) and insulin resistance scores (p=0.04), as well as with lower high-density lipoprotein cholesterol (p<0.01).
Compared with other breast cancer subtypes, oestrogen receptor (ER)-positive tumours correlated with greater body fat (p=0.03).
Furthermore, Taiwanese women had larger breast adipocytes despite lower BMI relative to US Caucasians (p=0.01).
The present data show that WAT inflammation is prevalent in Asian women with increased levels of body fat. Researchers noted that the increasing prevalence of ER+ breast cancers among premenopausal Asian women may be attributed to the local and systemic effects of WAT inflammation.
Additional studies are needed to determine whether reducing adiposity and WAT inflammation via interventions, such as structured diet modification and/or exercise programmes, can reduce breast cancer risk.