Physical Medicine and Rehabilitation, Vanderbilt University Medical Center, Nashville, TN, USA.
Vanderbilt Dayani Center for Health and Wellness, Nashville, TN, USA.
Breast Cancer Res Treat. 2020 Aug;183(1):83-94. doi: 10.1007/s10549-020-05765-5. Epub 2020 Jun 29.
Breast cancer treatment-related lymphedema (BCRL) evaluation is frequently performed using portable measures of limb volume and bioimpedance asymmetry. Here quantitative magnetic resonance imaging (MRI) is applied to evaluate deep and superficial tissue impairment, in both surgical and contralateral quadrants, to test the hypothesis that BCRL impairment is frequently bilateral and extends beyond regions commonly evaluated with portable external devices.
3-T MRI was applied to investigate BCRL topographical impairment. Female BCRL (n = 33; age = 54.1 ± 11.2 years; stage = 1.5 ± 0.8) and healthy (n = 33; age = 49.4 ± 11.0 years) participants underwent quantitative upper limb MRI relaxometry (T), bioimpedance asymmetry, arm volume asymmetry, and physical evaluation. Parametric tests were applied to evaluate study measurements (i) between BCRL and healthy participants, (ii) between surgical and contralateral limbs, and (iii) in relation to clinical indicators of disease severity. Two-sided p-value < 0.05 was required for significance.
Bioimpedance asymmetry was significantly correlated with MRI-measured water relaxation (T) in superficial tissue. Deep muscle (T = 37.6 ± 3.5 ms) and superficial tissue (T = 49.8 ± 13.2 ms) relaxation times were symmetric in healthy participants. In the surgical limbs of BCRL participants, deep muscle (T = 40.5 ± 4.9 ms) and superficial tissue (T = 56.0 ± 14.8 ms) relaxation times were elevated compared to healthy participants, consistent with an edematous micro-environment. This elevation was also observed in contralateral limbs of BCRL participants (deep muscle T = 40.3 ± 5.7 ms; superficial T = 56.6 ± 13.8 ms).
Regional MRI measures substantiate a growing literature speculating that superficial and deep tissue, in surgical and contralateral quadrants, is affected in BCRL. The implications of these findings in the context of titrating treatment regimens and understanding malignancy recurrence are discussed.
乳腺癌治疗相关淋巴水肿（BCRL）的评估通常采用便携式肢体容量和生物阻抗不对称性测量方法进行。这里应用定量磁共振成像（MRI）来评估手术和对侧象限的深层和浅层组织损伤，以检验这样一种假设，即 BCRL 损伤通常是双侧的，并超出了通常用便携式外部设备评估的区域。
应用 3-T MRI 来研究 BCRL 的局部损伤。33 名女性 BCRL（年龄 54.1 ± 11.2 岁；分期 1.5 ± 0.8）和 33 名健康女性（年龄 49.4 ± 11.0 岁）参与者接受了定量上肢 MRI 弛豫度（T）、生物阻抗不对称性、手臂容量不对称和体格评估。应用参数检验评估 BCRL 与健康参与者之间的研究测量值（i），评估手术侧与对侧肢体之间的研究测量值（ii），以及评估与疾病严重程度的临床指标之间的关系。需要双侧 p 值<0.05 才有统计学意义。
生物阻抗不对称性与浅层组织中 MRI 测量的水弛豫（T）显著相关。健康参与者的深层肌肉（T=37.6 ± 3.5 ms）和浅层组织（T=49.8 ± 13.2 ms）弛豫时间是对称的。在 BCRL 参与者的手术肢体中，与健康参与者相比，深层肌肉（T=40.5 ± 4.9 ms）和浅层组织（T=56.0 ± 14.8 ms）弛豫时间升高，提示存在水肿的微环境。在 BCRL 参与者的对侧肢体中也观察到这种升高（深层肌肉 T=40.3 ± 5.7 ms；浅层 T=56.6 ± 13.8 ms）。
区域性 MRI 测量结果证实了越来越多的文献推测，手术和对侧象限的浅层和深层组织都受到 BCRL 的影响。讨论了这些发现在调整治疗方案和理解恶性肿瘤复发方面的意义。
