Department of Clinical Sciences, Division of Oncology and Pathology, Lund University, Skåne University Hospital, Lund, Sweden.
Department of Translational Medicine, Medical Radiation Physics, Lund University, Skåne University Hospital, Malmö, Sweden.
Acta Oncol. 2020 Dec;59(12):1528-1537. doi: 10.1080/0284186X.2020.1830167. Epub 2020 Oct 16.
Neoadjuvant chemotherapy (NACT) is offered to an increasing number of breast cancer (BC) patients, and comprehensive monitoring of treatment response is of utmost importance. Several imaging modalities are available to follow tumor response, although likely to provide different clinical information. We aimed to examine the association between early radiological response by three conventional imaging modalities and pathological complete response (pCR). Further, we investigated the agreement between these modalities pre-, during, and post-NACT, and the accuracy of predicting pathological residual tumor burden by these imaging modalities post-NACT.
This prospective Swedish cohort study included 202 BC patients assigned to NACT (2014-2019). Breast imaging with clinically used modalities: mammography, ultrasound, and tomosynthesis was performed pre-, during, and post-NACT. We investigated the agreement of tumor size by the different imaging modalities, and their accuracy of tumor size estimation. Patients with a radiological complete response or radiological partial response (≥30% decrease in tumor diameter) during NACT were classified as radiological early responders.
Patients with an early radiological response by ultrasound had 2.9 times higher chance of pCR than early radiological non-responders; the corresponding relative chance for mammography and tomosynthesis tumor size measures was 1.8 and 2.8, respectively. Post-NACT, each modality, separately, could accurately estimate tumor size (within 5 mm margin compared to pathological evaluation) in 43-46% of all tumors. The diagnostic precision in predicting pCR post-NACT was similar between the three imaging modalities; however, tomosynthesis had slightly higher specificity and positive predictive values.
Breast imaging modalities correctly estimated pathological tumor size in less than half of the tumors. Based on this finding, predicting residual tumor size post-NACT is challenging using conventional imaging. Patients with early radiological non-response might need improved monitoring during NACT and be considered for changed treatment plans.
新辅助化疗（NACT）越来越多地应用于乳腺癌（BC）患者，全面监测治疗反应至关重要。有多种影像学方法可用于监测肿瘤反应，但可能提供不同的临床信息。我们旨在检查三种常规影像学方法的早期放射学反应与病理完全缓解（pCR）之间的相关性。此外，我们还研究了这些影像学方法在 NACT 前、期间和之后的一致性，以及这些影像学方法在 NACT 后预测病理残留肿瘤负荷的准确性。
这是一项前瞻性瑞典队列研究，纳入了 202 例接受 NACT 治疗的 BC 患者（2014-2019 年）。在 NACT 前、期间和之后，对临床使用的乳腺成像方法：乳房 X 线摄影、超声和断层合成术进行了检查。我们研究了不同影像学方法测量肿瘤大小的一致性，并评估了它们的肿瘤大小估计准确性。在 NACT 期间具有完全或部分放射学反应（肿瘤直径减少≥30%）的患者被归类为早期放射学反应者。
与早期放射学无反应者相比，超声检查的早期放射学反应者发生 pCR 的可能性高 2.9 倍；乳房 X 线摄影和断层合成术的相应相对几率分别为 1.8 和 2.8。在 NACT 后，每种影像学方法单独在 43-46%的所有肿瘤中能够准确估计肿瘤大小（与病理评估相比，在 5mm 范围内）。在预测 NACT 后 pCR 方面，三种影像学方法的诊断精度相似；然而，断层合成术的特异性和阳性预测值略高。
乳腺影像学方法正确评估了不到一半肿瘤的病理肿瘤大小。基于这一发现，使用常规影像学预测 NACT 后残留肿瘤大小具有挑战性。对于早期放射学无反应的患者，在 NACT 期间可能需要更好的监测，并考虑改变治疗计划。
