Data Sheet 1_Baseline cross-sectional imaging of locally advanced high-risk breast cancer facilitates highly customized radiation therapy in surgically inaccessible anatomical areas.docx

BackgroundRoutine medical imaging used for preliminary breast cancer workup, such as mammography (MMG) and ultrasound (US), has limited utility for radiation oncologists. We hypothesized that the inclusion of cross-sectional imaging (CT scan or PET-CT) prior to primary systemic therapy (PST) would improve clinical staging accuracy and facilitate customized postoperative radiation therapy planning. Therefore, this study aimed to compare the standard baseline imaging with extended radiological staging.
MethodsTo assess our hypothesis, we performed a prospective, single-center study that included 132 participants who were recruited from October 2015 to March 2020. We quantified the value of cross-sectional imaging compared to those of MMG and US. Descriptive statistics, the Friedman and chi-square tests were performed, and p < 0.05 was considered significant.
ResultsPatients were grouped into two cohorts: the CT scan cohort (n = 87) and the PET-CT cohort (n = 43). A comparison of the value of cross-sectional imaging with those of MMG and US revealed that staging and radiation planning were altered by this additional procedure. The originally determined disease stage changed in 36.8% and 51.2% of cases in the first and second groups, respectively. The consistency between the assessment of involved axillary lymph nodes using imaging (cN) and the postoperative pathology report (pN) were evaluated. In most cases, clinical and pathological evaluation were consistent, with χ2(1) = 18.98; p < 0.001 for CT scan, and χ2(1) = 6.41; p = 0.03 for PET-CT.
ConclusionsCross-sectional imaging is recommended for patients with locally advanced high-risk breast cancer. A highly customized radiation therapy, including a dose boost, was administered in nine patients with affected lymph nodes that were surgically inaccessible. This procedure was facilitated by extended radiological staging.

背景：用于乳腺癌初步排查的常规医学影像检查，如乳腺钼靶摄影（mammography, MMG）与超声成像（ultrasound, US），对放射肿瘤医师（radiation oncologists）的临床应用价值有限。本研究假设，在初始全身治疗（primary systemic therapy, PST）前加用断层成像（cross-sectional imaging，包括CT扫描或PET-CT），可提升临床分期准确性，并助力个体化术后放射治疗计划的制定。因此，本研究旨在对比标准基线影像与扩展放射学分期的应用效果。
方法：为验证本研究假设，我们开展了一项前瞻性单中心研究，于2015年10月至2020年3月间纳入132名受试者。本研究量化对比了断层成像与MMG、US的临床应用价值，采用描述性统计、Friedman检验及卡方检验进行数据分析，以p<0.05为差异具有统计学意义。
结果：受试者被分为两个队列：CT扫描队列（n=87）与PET-CT队列（n=43）。对比断层成像与MMG、US的应用价值可见，额外加用断层成像可改变患者分期与放射治疗计划。在CT扫描队列与PET-CT队列中，分别有36.8%与51.2%的病例原分期发生了调整。本研究还评估了影像评估的受累腋窝淋巴结（cN）与术后病理报告（pN）的一致性。多数病例的临床评估与病理评估结果一致：CT扫描队列的χ²(1)=18.98，p<0.001；PET-CT队列的χ²(1)=6.41，p=0.03。
结论：推荐局部晚期高危乳腺癌患者接受断层成像检查。9名存在手术无法切除的受累淋巴结的患者接受了包括剂量推量在内的高度个体化放射治疗，而扩展放射学分期为该治疗方案的实施提供了支持。