Breast cancer (BC) is the most prevalent tumor in women. Improvements in treatment led to declined mortality, resulting in more survivors living with cancer- or therapy-induced comorbidities. In this study, we investigated the impact of neoplasia and chemotherapy on resting energy expenditure (REE) and body composition, in relation to cancer-related fatigue. Inflammatory parameters were checked as possible explanation for changes in REE. Fifty-six women participated: 20 women with BC and 36 healthy controls. Patients were assessed at baseline (T0) and follow-up (T1) after 12 weeks of chemotherapy. Controls were measured once. REE was assessed with indirect calorimetry: body composition (body weight, fat mass, fat-free mass) by air plethysmography. The multidimensional fatigue index (MFI-20) was used to analyze fatigue. Baseline measurements of patients were compared to results of the healthy controls with the independent-samples T-test. The paired-samples T-test investigated the effects of chemotherapy from T0 to T1. A Pearson correlation analysis was conducted between REE, body composition, and fatigue and between REE, body composition, and inflammatory parameters. A linear regression analysis was fitted to estimate the contribution of the significantly correlated parameters. The measured REE at T0 and T1 was compared to the predicted REE to analyze the clinical use of the latter. At baseline, patients with BC had significantly higher REE in the absence of differences in body composition. From baseline to T1, REE and body weight did not change. In contrast, fat-free mass declined significantly with concordant increase in fat mass. Fatigue deteriorated significantly. C-reactive protein at baseline predicted the change in energy expenditure. Predicted REE significantly underestimated measured REE. Women with BC have higher REE in the tumor-bearing state compared to healthy controls. Chemotherapy does not affect REE but alters body composition. Predictive equations are invalid in the BC population. Results of our study can be used to implement personalized nutritional interventions to support energy expenditure and body composition and minimize long-term comorbidities.

中文翻译：

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化疗对乳腺癌女性静息能量消耗、身体成分和癌症相关疲劳的影响：一项前瞻性队列研究

乳腺癌（BC）是女性中最常见的肿瘤。治疗方法的改进导致死亡率下降，导致更多的幸存者患有癌症或治疗引起的合并症。在这项研究中，我们调查了肿瘤和化疗对静息能量消耗 (REE) 和身体成分的影响，以及与癌症相关的疲劳的关系。检查炎症参数作为 REE 变化的可能解释。56 名女性参与其中：20 名患有 BC 的女性和 36 名健康对照者。化疗 12 周后，患者在基线 (T0) 和随访 (T1) 时接受评估。对照测量一次。通过间接量热法评估稀土元素：通过空气体积描记法评估身体成分（体重、脂肪量、去脂量）。采用多维疲劳指数（MFI-20）来分析疲劳。通过独立样本 T 检验将患者的基线测量结果与健康对照的结果进行比较。配对样本 T 检验研究了从 T0 到 T1 的化疗效果。在 REE、身体成分和疲劳之间以及 REE、身体成分和炎症参数之间进行皮尔逊相关分析。拟合线性回归分析来估计显着相关参数的贡献。将 T0 和 T1 时测量的 REE 与预测的 REE 进行比较，以分析后者的临床应用。在基线时，在身体成分没有差异的情况下，BC 患者的 REE 显着较高。从基线到 T1，REE 和体重没有变化。相比之下，去脂体重显着下降，而脂肪质量则相应增加。疲劳感明显恶化。基线时的 C 反应蛋白可预测能量消耗的变化。预测的稀土元素显着低估了测量的稀土元素。与健康对照组相比，患有 BC 的女性在荷瘤状态下的 REE 含量更高。化疗不会影响 REE，但会改变身体成分。预测方程在 BC 人群中无效。我们的研究结果可用于实施个性化营养干预措施，以支持能量消耗和身体成分，并最大限度地减少长期合并症。