Division of Hematology and Oncology, Indiana University School of Medicine, Indianapolis, Indiana.
School of Informatics and Computing, Indiana University Purdue University Indianapolis, Indianapolis, Indiana.
Cancer. 2022 Jun 1;128(11):2174-2181. doi: 10.1002/cncr.34173. Epub 2022 Mar 14.
African ancestry (AA) and obesity are associated with worse survival in early-stage breast cancer. Obesity disproportionately affects women of AA; however, the intersection between ancestry and obesity on breast cancer outcomes remains unclear.
A total of 2854 patients in the adjuvant trial E5103 were analyzed. Genetic ancestry was determined using principal components from a genome-wide array. The impact of continuous or binary body mass index (BMI) on disease-free survival (DFS) and overall survival (OS) was evaluated by multivariable Cox proportional hazards models in AA patients and European ancestry (EA) patients.
There were 2471 EA patients and 383 AA patients. Higher BMI was significantly associated with worse DFS and OS only in AA patients (DFS hazard ratio [HR], 1.25; 95% CI, 1.07-1.46; OS HR, 1.38; 95% CI, 1.10-1.73), not in EA patients (DFS HR, 0.97; 95% CI, 0.90-1.05; OS HR, 1.03; 95% CI, 0.93-1.14). Severe obesity (BMI ≥40) was significantly associated with worse survival in AA patients (DFS HR, 2.04; 95% CI, 1.21-3.43; OS HR, 2.21; 95% CI, 1.03-4.75) but had no impact on that of EA patients. In the estrogen receptor-positive (ER+) and triple-negative breast cancer subgroups, BMI was significantly associated with worse outcomes only in those AA patients with ER+ disease. Within the AA group, BMI remained associated with worse survival regardless of the AA proportion.
Higher BMI was statistically significantly associated with worse breast cancer outcomes in AA but not EA patients. This association was most significant for severe obesity and those with ER+ disease. These observations help define optimal populations for weight change interventions designed to affect disparities and survival in early-stage breast cancer.
African ancestry and obesity are both risk factors for worse survival after early-stage breast cancer. Women of African descent are also disproportionately affected by obesity; however, it is unclear what impact body weight has on racial disparities in breast cancer. Data from a large phase 3 clinical trial in high-risk, early-stage breast cancer were used to determine how body weight affects survival outcomes in European versus African Americans. Study results demonstrate that a higher body mass index is associated with increased risk of breast cancer recurrence and worse survival in women of African ancestry but not in women of European ancestry.
非裔（AA）和肥胖与早期乳腺癌患者的生存预后较差有关。肥胖对 AA 女性的影响不成比例；然而，遗传背景和肥胖对乳腺癌结局的相互影响仍不清楚。
分析辅助试验 E5103 中的 2854 例患者。使用全基因组数组中的主成分确定遗传背景。在 AA 患者和欧洲血统（EA）患者中，通过多变量 Cox 比例风险模型评估连续或二元体重指数（BMI）对无病生存（DFS）和总生存（OS）的影响。
EA 患者 2471 例，AA 患者 383 例。较高的 BMI 仅与 AA 患者的 DFS 和 OS 显著相关（DFS 风险比[HR]，1.25；95%CI，1.07-1.46；OS HR，1.38；95%CI，1.10-1.73），而与 EA 患者无相关性（DFS HR，0.97；95%CI，0.90-1.05；OS HR，1.03；95%CI，0.93-1.14）。严重肥胖（BMI≥40）与 AA 患者的生存预后显著相关（DFS HR，2.04；95%CI，1.21-3.43；OS HR，2.21；95%CI，1.03-4.75），但对 EA 患者无影响。在雌激素受体阳性（ER+）和三阴性乳腺癌亚组中，BMI 仅与 AA 患者的 ER+疾病相关，与较差的预后显著相关。在 AA 组中，无论 AA 比例如何，BMI 与生存预后仍然相关。
较高的 BMI 与 AA 而非 EA 患者的乳腺癌预后较差具有统计学显著相关性。这种相关性在严重肥胖和 ER+疾病患者中最为显著。这些观察结果有助于确定最佳人群，以便进行旨在影响早期乳腺癌的差异和生存的体重改变干预措施。
非裔和肥胖都是早期乳腺癌患者生存预后较差的危险因素。非洲裔美国人也受到肥胖的不成比例影响；然而，体重对乳腺癌种族差异的影响尚不清楚。来自高危早期乳腺癌的大型 III 期临床试验的数据用于确定体重如何影响欧洲裔和非裔美国人的生存结果。研究结果表明，较高的体重指数与非裔美国女性的乳腺癌复发风险增加和生存预后较差相关，但与欧洲裔女性无关。
