Association of Overweight with Breast Cancer Survival

Abstract

The authors investigated the association between overweight at the time of or soon after cancer diagnosis and survival in a cohort of 1,455 breast cancer patients aged 25-64 years. The patients were recruited into the Shanghai Breast Cancer Study (Shanghai, China), a population-based case-control study, between August 1996 and March 1998. The median follow-up time for this cohort was 5.1 years (1996-2002) after breast cancer diagnosis, and 240 deaths were identified. Being overweight at cancer diagnosis or soon afterward, as measured by body mass index (BMI; weight (kg)/height (m)(2)), was associated with poorer overall survival and disease-free survival. Five-year survival rates were 86.5%, 83.8%, and 80.1% for subjects whose BMIs were <23.0, 23.0-24.9, and >or=25.0, respectively (p = 0.02); the corresponding 5-year disease-free survival rates were 81.9%, 78.1%, and 76.6% (p = 0.05). The inverse association between BMI and survival persisted after adjustment for age at diagnosis and other known prognostic factors for breast cancer, including disease stage. The authors found neither waist:hip ratio nor waist circumference to be independently associated with overall survival or disease-free survival. These results suggest that excess weight may be an independent predictor of breast cancer survival among Chinese women.

Body mass index and risk of all‐cause and cardiovascular mortality in hospitalized elderly patients with diabetes mellitus

“…These findings are consistent with those observed in other high-risk patient populations [12][13][14][15]. In the general population, the association between BMI and all-cause mortality appears to be 'U' or 'J' shaped [16].…”

Obesity and Survival Among Black Women and White Women 35 to 64 Years of Age at Diagnosis With Invasive Breast Cancer

“…30 Furthermore, adipose tissue produces leptin and a group of other growth factors (eg, interleukin-6, tumor necrosis factor-␣, vascular endothelial growth factor) that may stimulate angiogenesis, lead to more rapid growth of malignant cells, and promote metastasis. [31][32][33] Another possible explanation for the adverse effect of obesity on mortality is attributed to the more advanced tumor stage associated with obesity. [33][34][35] Among women with nonlocalized tumors, but not among women with localized tumors, we observed increased risk of mortality with obesity, especially breast cancer-specific mortality, for both black women and white women.…”

Effect of 2,3,7,8-tetrachlorodibenzo-p-dioxin administration and high-fat diet on the body weight and hepatic estrogen metabolism in female C3H/HeN mice

“…Here it is also of relevance to note that many of the Vietnam War veterans were exposed to high levels of TCDD [52,53], and significant residues of this chemical have been found in their serum samples even after many years [38]. One of the most consistently identified diseases that were associated with TCDD exposure is the Type 2 diabetes mellitus [54][55][56].…”

“…There were a number of reasons for the inclusion of a HF diet as a subgroup in the present study: (i) Studies have demonstrated that certain fatty acids and/or their metabolites can serve effectively as natural ligands for some of the nuclear receptors which regulate the expression of drug-metabolizing enzymes as well as liver growth [34][35][36]. (ii) Recent epidemiological studies have suggested that obesity is an important risk factor for human breast cancer [37,38], but little is known about the modulating effect of a HF diet on hepatic estrogen metabolism as well as on the metabolizing enzyme-inducing activity of AhR ligands. Therefore, we believed it would be of interest to also determine the potential interactions between dietary fatty acids and TCDD with respect to their effects on animal body and organ weights as well as on hepatic enzyme levels for estrogen metabolism.…”