Supplementary Material for: Factors Influencing Decision-Making for or against Adjuvant and Neoadjuvant Chemotherapy in Postmenopausal Hormone Receptor-Positive Breast Cancer Patients in the EvAluate-TM Study

<i>Background:</i> Decision-making for or against neoadjuvant or adjuvant chemotherapy in postmenopausal patients with hormone receptor-positive breast cancer does not follow any clear guidelines, and some patients may unnecessarily undergo chemotherapy and be exposed to the associated toxicity. The aim of this study was to identify the patient population for whom this issue may bear relevance. <i>Methods:</i>Patients being treated with letrozole in the prospective multicenter noninterventional EvAluate-TM study were recruited. The percentage of patients receiving chemotherapy and factors associated with chemotherapy administration were identified. <i>Results:</i> In all, 3,924 (37.4%) patients received chemotherapy before treatment with letrozole. Of these, 293 (20%) underwent neoadjuvant therapy. Younger age was predictive for both adjuvant and neoadjuvant therapy. Overall, decisions in favor of administering chemotherapy are more likely to be made in patients with a higher body mass index (BMI), and neoadjuvant chemotherapy is administered at a higher rate in women with a lower BMI. Concomitant medication influenced the overall decision-making regarding chemotherapy, irrespective of whether it was given on a neoadjuvant or adjuvant basis. <i>Conclusion:</i> There is an ongoing debate as to whether all of the many patients who receive chemotherapy actually benefit from it. Neoadjuvant chemotherapy is frequently administered in this patient population, and this should encourage further research to resolve current clinical and research issues.

<i>背景：</i>绝经后激素受体阳性乳腺癌（hormone receptor-positive breast cancer）患者选择新辅助化疗（neoadjuvant chemotherapy）或辅助化疗（adjuvant chemotherapy）的决策尚无明确统一的临床指南，部分患者可能接受不必要的化疗，进而承受与之相关的毒性反应。本研究旨在明确该临床问题具有实际意义的患者人群。
<i>方法：</i>本研究纳入了在一项前瞻性多中心非干预性EvAluate-TM研究中接受来曲唑（letrozole）治疗的患者，统计了接受化疗的患者占比，并明确了与化疗实施相关的影响因素。
<i>结果：</i>总计3924例（37.4%）患者在接受来曲唑治疗前接受了化疗。其中293例（20%）接受了新辅助治疗。患者年龄较轻是辅助化疗与新辅助化疗的共同预测因素。总体而言，体质量指数（Body Mass Index, BMI）较高的患者更有可能被选择接受化疗；而体质量指数较低的女性新辅助化疗的实施比例更高。合并用药会影响化疗相关的整体决策，无论该化疗属于新辅助还是辅助治疗范畴。
<i>结论：</i>目前学界仍存在争议：接受化疗的众多患者是否均能从中获益。该患者人群中频繁实施新辅助化疗，这一现状应推动后续研究以解决当前存在的临床与科研问题。