HealthDay News — High body fat levels are associated with elevated risk of estrogen receptor (ER)-positive breast cancer in postmenopausal women with normal body mass index (BMI), according to a study presented at the American Association for Cancer Research Special Conference — Obesity and Cancer: Mechanisms Underlying Etiology and Outcomes — held from Jan. 27 to 30 in Austin, Texas.
Neil Iyengar, MD, from the Memorial Sloan Kettering Cancer Center in New York City, and colleagues examined the correlation between body fat levels and breast cancer risk among women with normal BMI.
The study was conducted in the Women’s Health Initiative and included 3460 postmenopausal women with BMI of 18.5 to < 25 kg/m². A total of 182 incident invasive cancers were ascertained by a median follow-up of 16 years, of which 146 were ER-positive.
The researchers found that the multivariable-adjusted hazard ratios were 1.7 and 1.75 for invasive breast cancer in the highest vs lowest quartile of whole-body fat mass and trunk fat mass, respectively.
The corresponding adjusted hazard ratios for ER-positive breast cancer were 2.1 and 1.91. After adjustment for waist-hip ratio, the associations remained statistically significant.
“Our findings show that the risk of invasive breast cancer is increased in postmenopausal women with normal BMI and higher levels of body fat, meaning that a large proportion of the population has an unrecognized risk of developing cancer,” Dr Iyengar said in a statement.
High body fat levels are associated with increased breast cancer risk in postmenopausal women with normal BMI (news release). Austin, TX: AACR; January 26, 2018. Accessed February 12, 2018.