Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, 9609 Medical Center Drive, Rm 7E142, Bethesda, MD, 20892, USA.
Division of Research, Kaiser Permanente Northern California, Oakland, CA, USA.
Breast Cancer Res Treat. 2020 Sep;183(2):467-478. doi: 10.1007/s10549-020-05785-1. Epub 2020 Jul 20.
Inflammatory breast cancer (IBC) is a rare, poorly understood and aggressive tumor. We extended prior findings linking high body mass index (BMI) to substantial increased IBC risk by examining BMI associations before and after adjustment for well-characterized comorbidities using medical record data for diabetes, insulin resistance, and disturbances of cholesterol metabolism in a general community healthcare setting.
We identified 247 incident IBC cases diagnosed at Kaiser Permanente Northern California between 2005 and 2017 and 2470 controls matched 10:1 on birth year and geographic area and with ≥ 13 months of continuous enrollment prior to diagnosis/index date. We assessed exposures from 6 years up to one year prior to the diagnosis/index date, using logistic regression to calculate odds ratios (ORs) with 95% confidence intervals (CIs).
Before adjustment for comorbidities, ORs (95% CIs) for BMI of 25-< 30, 30-< 35, and ≥ 35 compared to < 25 kg/m were 1.5 (0.9-2.3), 2.0 (1.2-3.1), and 2.5 (1.4-4.4), respectively. After adjustment for pre-diabetes/diabetes, HDL-C and triglyceride levels, and dyslipidemia, corresponding ORs were 1.3 (0.8-2.1), 1.6 (0.9-2.9), and 1.9 (1.0-3.5). The OR for HDL-C levels < 50 mg/dL compared to ≥ 65 mg/dL was 2.0 (1.2-3.3) in the adjusted model. In a separate model the OR for a triglyceride/HDL-C ratio ≥ 2.50 compared to < 1.62 was 1.7 (1.1-2.8) after adjustment for BMI, pre-diabetes/diabetes, and dyslipidemia. Results did not differ significantly by estrogen receptor status.
Obesity and measures of insulin resistance independently increased IBC risk as did obesity and low HDL-C levels. These findings, if confirmed, have implications for IBC prevention.
炎性乳腺癌（IBC）是一种罕见的、了解甚少且侵袭性很强的肿瘤。我们利用病历数据，扩展了之前关于高体重指数（BMI）与 IBC 风险显著增加相关的发现，在一般社区医疗环境中，针对糖尿病、胰岛素抵抗和胆固醇代谢紊乱等明确的合并症，在调整前和调整后都对 BMI 进行了关联分析。
我们在 2005 年至 2017 年期间，在 Kaiser Permanente Northern California 确定了 247 例 IBC 病例，并按出生年份和地理区域以 10:1 的比例匹配了 2470 例对照，且在诊断/索引日期之前有≥13 个月的连续入组。我们使用逻辑回归，在诊断/索引日期前 6 年到一年的时间内评估了暴露情况，并计算了比值比（OR）及其 95%置信区间（CI）。
在未调整合并症的情况下，与 BMI<25kg/m2相比，BMI 为 25-<30kg/m2、30-<35kg/m2 和≥35kg/m2 的 OR（95%CI）分别为 1.5（0.9-2.3）、2.0（1.2-3.1）和 2.5（1.4-4.4）。在调整了前驱糖尿病/糖尿病、高密度脂蛋白胆固醇（HDL-C）和甘油三酯水平以及血脂异常后，相应的 OR 分别为 1.3（0.8-2.1）、1.6（0.9-2.9）和 1.9（1.0-3.5）。在调整模型中，与 HDL-C 水平≥65mg/dL 相比，HDL-C 水平<50mg/dL 的 OR 为 2.0（1.2-3.3）。在另一项模型中，在调整 BMI、前驱糖尿病/糖尿病和血脂异常后，与三酰甘油/高密度脂蛋白胆固醇（TG/HDL-C）比值<1.62 相比，TG/HDL-C 比值≥2.50 的 OR 为 1.7（1.1-2.8）。雌激素受体状态的结果无显著差异。
肥胖和胰岛素抵抗的指标独立增加了 IBC 的风险，肥胖和低 HDL-C 水平也是如此。如果这些发现得到证实，将对 IBC 的预防产生影响。
