Department of Radiation Oncology, and Physical Sciences, Sunnybrook Health Sciences Centre, Toronto, ON, Canada; Department of Radiation Oncology and Medical Biophysics, University of Toronto, Toronto, ON, Canada.
Department of Radiation Oncology, and Physical Sciences, Sunnybrook Health Sciences Centre, Toronto, ON, Canada.
Med Image Anal. 2015 Feb;20(1):224-36. doi: 10.1016/j.media.2014.11.009. Epub 2014 Nov 25.
Tumor response to neoadjuvant chemotherapy in patients (n=30) with locally advanced breast cancer (LABC) was examined using quantitative ultrasound. Three ultrasound backscatter parameters, the integrated backscatter coefficient (IBC), average scatterer diameter (ASD), and average acoustic concentration (AAC), were estimated from tumors prior to treatment and at four times during neoadjuvant chemotherapy treatment (weeks 0, 1, 4, 8, and prior to surgery) and compared to ultimate clinical and pathological tumor responses. Results demonstrated that among all parameters, AAC was the best indicator of tumor response early after starting treatment. The AAC parameter increased substantially in treatment-responding patients as early as one week after treatment initiation, further increased at week 4, and attained a maximum at week 8. In contrast, the backscatter parameters from non-responders did not show any changes after treatment initiation. The two patient populations exhibited a statistically significant difference in changes of AAC (p<0.001) and ASD (p=0.023) over all treatment times examined. The best prediction of treatment response was achieved with the combination of AAC and ASD at week 4 (82% sensitivity, 100% specificity, and 86% accuracy) of 12-18 weeks of treatment. The survival of patients with responsive ultrasound parameters was higher than patients with non-responsive ultrasound parameters (35 ± 11 versus 27 ± 11 months, respectively, p=0.043). This study demonstrates that ultrasound parameters derived from the ultrasound backscattered power spectrum can potentially serve as non-invasive early measures of clinical tumor response to chemotherapy treatments.
采用定量超声技术检测了 30 例局部晚期乳腺癌（LABC）患者新辅助化疗的肿瘤反应。在治疗前和新辅助化疗治疗期间的 4 个时间点（治疗开始时的第 0、1、4 和 8 周，以及手术前），从肿瘤中估算了三种超声背散射参数，即积分背散射系数（IBC）、平均散射体直径（ASD）和平均声浓度（AAC），并将其与最终的临床和病理肿瘤反应进行了比较。结果表明，在所有参数中，AAC 是治疗开始后早期肿瘤反应的最佳指标。在开始治疗后仅一周，治疗反应患者的 AAC 参数就显著增加，在第 4 周进一步增加，并在第 8 周达到最大值。相比之下，无反应患者的背散射参数在治疗开始后没有任何变化。两组患者在所有治疗时间点的 AAC（p<0.001）和 ASD（p=0.023）变化上均表现出统计学上的显著差异。在治疗开始后 12-18 周（第 4 周），AAC 和 ASD 的联合最佳预测治疗反应，其敏感性为 82%，特异性为 100%，准确性为 86%。具有响应性超声参数的患者的生存率高于具有无响应性超声参数的患者（分别为 35±11 个月和 27±11 个月，p=0.043）。本研究表明，超声背散射功率谱中得出的超声参数可能可作为化疗治疗临床肿瘤反应的非侵入性早期测量指标。
