Arenas Meritxell, Hernández Víctor, Farrús Blanca, Müller Katrin, Gascón Marina, Pardo Alida, Berenguer Roberto, Sabater Sebastia
Hospital Universitari Sant Joan, Radiation Oncology, Institut d'Investigacions Sanit ries Pere Virgili (IISPV), Universitat Rovira i Virgili (URV) , Reus , Spain.
Acta Oncol. 2014 Jun;53(6):795-801. doi: 10.3109/0284186X.2014.893062. Epub 2014 Mar 21.
Treating patients with large or pendulous breasts is challenging. Although brassiere cups are currently in use, no study has yet been carried out to assess their dosimetric impact. The aim of the present study was to evaluate the possible dosimetric advantages of the use of breast cups on patients with large or pendulous breasts.
Two CT studies were carried out on 12 breast cancer patients with large or pendulous breasts, with one study involving the use of breast cups. Radiation plans were developed in accordance with each of the CT studies. The following were compared: planning target volume (PTV), volume irradiated by the 95% isodose, conformity index, homogeneity index, mean lung dose, and mean heart dose was also compared for left breast treatment. The plan involving the use of cups was found to be the best option, leading to all patients being treated with cups. The resulting acute toxicity and cosmesis were also recorded. Both scenarios involved the use of film dosimetry to evaluate the skin doses.
The use of breast cups resulted in a significant reduction of the PTV volume (from 1640 cm3 to 1283 cm3), of the irradiated volume (from 2154 cm3 to 1477 cm3) and of the conformity index (from 1383 to 1213). Despite slight improvements in the homogeneity index (from 0.12 to 0.10), statistical significance was not attained. The use of breast cups also led to significant dose reductions in V20 for lung (from 13.7% to 1.7%) and V5 for heart (from 9.8% to 2.7%). No differences in acute toxicity or cosmesis were observed compared to patients treated without cups.
Our results show that the use of brassiere cups during breast radiation therapy leads to improvements in the main dosimetric factors analyzed. Furthermore, modifications to standard irradiation protocols are not required. In summary, we consider the technique of using breast cups with radiation therapy highly appropriate when treating breast cancer patients with large or pendulous breasts.
治疗乳房较大或下垂的患者具有挑战性。尽管目前使用胸罩杯，但尚未开展研究评估其剂量学影响。本研究的目的是评估对乳房较大或下垂的患者使用胸罩杯可能具有的剂量学优势。
对12例乳房较大或下垂的乳腺癌患者进行了两次CT研究，其中一项研究使用了胸罩杯。根据每项CT研究制定放射治疗计划。比较了以下指标：计划靶体积（PTV）、95%等剂量线所照射的体积、适形指数、均匀性指数，对于左侧乳房治疗还比较了平均肺剂量和平均心脏剂量。发现使用胸罩杯的计划是最佳选择，从而所有患者均采用胸罩杯进行治疗。还记录了由此产生的急性毒性和美容效果。两种情况均使用胶片剂量测定法评估皮肤剂量。
使用胸罩杯使PTV体积显著减小（从1640 cm³降至1283 cm³）、照射体积显著减小（从2154 cm³降至1477 cm³）以及适形指数显著减小（从1383降至1213）。尽管均匀性指数略有改善（从0.12降至0.10），但未达到统计学显著性。使用胸罩杯还使肺部的V20剂量显著降低（从13.7%降至1.7%）以及心脏的V5剂量显著降低（从9.8%降至2.7%）。与未使用胸罩杯治疗的患者相比，未观察到急性毒性或美容效果方面的差异。
我们的结果表明，在乳房放射治疗期间使用胸罩杯可使所分析的主要剂量学因素得到改善。此外，无需对标准照射方案进行修改。总之，我们认为对乳房较大或下垂的乳腺癌患者进行治疗时，将胸罩杯与放射治疗结合使用的技术非常合适。
