le Guevelou J, Trompier F, Villagrasa C, Vela A, Isambert A, Herault J, Thariat J
Service de radiothérapie, centre François Baclesse, avenue du Général-Harris, 14000 Caen, France.
Laboratoire de dosimétrie des radiations ionisantes, Institut de radioprotection et de sûreté nucléaire (IRSN), 92262 Fontenay-aux-Roses, France.
Cancer Radiother. 2020 Apr;24(2):138-142. doi: 10.1016/j.canrad.2019.10.004. Epub 2020 Feb 13.
The decision to irradiate during pregnancy is based on a risk benefit compromise of two kinds: maternal risk and fetal risk. The aim of this work is to determine the foetal risk, and uterine dose measurement in proton therapy. Foetal exposure during treatment is linked to two sources: the treatment phase, and the repositioning phase. An Alderson-Rando anthropomorphic ghost (170cm, 74kg) was positioned on the table in the treatment position. A tissue-equivalent proportional counter (TEPC), adapted to the analysis of complex radiation fields (neutron and photonics), was used to determine the irradiation related to the treatment phase. An AT1123 radiation survey meter was used to measure photons generated by X-ray radiation. I dosimetry was proposed using radio-photoluminescent dosimeters, allowing for a daily check of the dose received in the uterus. The treatment phase produces higher uterine doses than the positioning phase, but these remain very low. The equivalent dose received in the uterus for the entire treatment is estimated at 840 μSv. Using a methodology for measuring the out-of-field dose with pencil beam scanning proton therapy, the foetal dose in the first trimester was well below the acceptance dose of 100 mGy determined by the International Commission on Radiological Protection.
母体风险和胎儿风险。这项工作的目的是确定质子治疗中的胎儿风险以及子宫剂量测量。治疗期间胎儿受到的照射与两个来源有关：治疗阶段和重新定位阶段。将一个Alderson-Rando人体模型（身高170厘米，体重74千克）放置在治疗位置的治疗台上。使用一个适用于分析复杂辐射场（中子和光子）的组织等效比例计数器（TEPC）来确定与治疗阶段相关的照射。使用AT1123辐射检测仪测量X射线辐射产生的光子。建议使用放射光致发光剂量计进行剂量测定，以便每天检查子宫所接受的剂量。治疗阶段产生的子宫剂量高于定位阶段，但这些剂量仍然非常低。整个治疗过程中子宫所接受的当量剂量估计为840微希沃特。使用铅笔束扫描质子治疗测量野外剂量的方法，孕早期的胎儿剂量远低于国际放射防护委员会确定的100毫戈瑞的可接受剂量。
