Gloi Aime M, Buchanan Robert
St Vincent Hospital Green Bay WI, USA.
J Med Phys. 2012 Jul;37(3):138-44. doi: 10.4103/0971-6203.99234.
The aim of this study was to compare lumpectomy cavity depth measurements obtained through ultrasound (U/S) and retrospective computed tomography (CT). Twenty-five patients with stage T1-2 invasive breast cancer formed the cohort of this study. Their U/S and CT measurements were converted into electron energy and compared. The mean U/S depth was 3.6 ± 1.3 cm, while the mean CT depth was 4.9 ± 1.9 cm; the listed error ranges are one standard deviation. Electron energies for treatment ranged from 6 MeV to 12 MeV based on the U/S determination. There was no significant correlation between cavity depths measured by U/S and CT (R(2)= 0.459, P < 0.002). Furthermore, only 20% of CT-based electron energy determinations matched the corresponding U/S determinations. This ratio increased to 40% when taking into account an upper limit based on the depth of organs at risk below the cavity. The study shows that there is a significant discrepancy between cavity depths determined by U/S and CT. It also supports the concept that post-lumpectomy radiotherapy boosts should be tailored according to the needs and comfort of individual practices and institutions.
本研究的目的是比较通过超声（U/S）和回顾性计算机断层扫描（CT）获得的乳房肿瘤切除术腔深度测量值。25例T1-2期浸润性乳腺癌患者构成了本研究队列。将他们的超声和CT测量值转换为电子能量并进行比较。超声测量的平均深度为3.6±1.3厘米，而CT测量的平均深度为4.9±1.9厘米；列出的误差范围为一个标准差。根据超声测定，治疗用电子能量范围为6兆电子伏特至12兆电子伏特。超声和CT测量的腔深度之间无显著相关性（R(2)=0.459，P<0.002）。此外，仅20%基于CT的电子能量测定与相应的超声测定相匹配。当考虑到腔下方危险器官深度的上限时，该比例增至40%。该研究表明，超声和CT测定的腔深度之间存在显著差异。它还支持这样一种观念，即乳房肿瘤切除术后放疗增敏应根据个体实践和机构的需求及便利性进行调整。
