Neal A J, Mayles W P, Yarnold J R
Joint Department of Physics, Royal Marsden Hospital, Sutton, Surrey, UK.
Br J Radiol. 1994 Dec;67(804):1149-54. doi: 10.1259/0007-1285-67-804-1149.
In recent years there have been great advances and innovations in all technical aspects of radiotherapy, including three dimensional (3D) computer planning, patient immobilization, radiation delivery and treatment verification. Despite this progress, the technique of tangential breast irradiation has changed little over this period and has not exploited these advances. There is increasing evidence that dose inhomogeneity within the breast is greater than at other anatomical sites, especially in women with large breasts. This paper is a review of the factors contributing to poor dosimetry in the breast, the clinical consequences of an inhomogeneous dose distribution, and how breast dosimetry could be improved by considering each of the stages from planning to accurate treatment delivery. It also highlights the particular problem of women with large breasts who may be more likely to have a poorer cosmetic outcome after a fractionated course of radiotherapy than women with small/medium-sized breasts, and supports the clinical impression that such women are also more likely to have greater dose inhomogeneity when 3D treatment plans are examined. Preliminary data from our current computed tomography (CT) planning study are presented to support these observations.
近年来，放射治疗的所有技术方面都取得了巨大进展和创新，包括三维（3D）计算机规划、患者固定、放射治疗和治疗验证。尽管取得了这一进展，但在此期间，乳腺切线照射技术变化不大，也未利用这些进展。越来越多的证据表明，乳腺内的剂量不均匀性比其他解剖部位更大，尤其是在乳房较大的女性中。本文综述了导致乳腺剂量测定不佳的因素、剂量分布不均匀的临床后果，以及如何通过考虑从规划到精确治疗实施的各个阶段来改善乳腺剂量测定。它还强调了乳房较大的女性所面临的特殊问题，与乳房中小的女性相比，她们在分次放射治疗疗程后可能更有可能出现较差的美容效果，并支持这样一种临床印象，即当检查三维治疗计划时，这些女性也更有可能出现更大的剂量不均匀性。本文还展示了我们当前计算机断层扫描（CT）规划研究的初步数据，以支持这些观察结果。
