Nicolas Camille, Petit Claire, Tallet Agnès, Boher Jean-Marie, Varela Cagetti Leonel, Favrel Veronique, Gonzague Casabianca Laurence, Guenole Morgan, Mailleux Hugues, Darreon Julien, Bannier Marie, Cohen Monique, Sabiani Laura, Tallet Camille, Teyssandier Charlene, Gonçalves Anthony, De Nonneville Alexandre, Lopez Almeida Leonor, Coste Nathan, Tyran Marguerite, Houvenaeghel Gilles
Department of Radiotherapy, Institut Paoli-Calmettes, 13009 Marseille, France.
Biostatistics and Methodology Unit, Institut Paoli-Calmettes, INSERM (National Institute of Health and Medical Research), IRD (Development Research Institute), Aix Marseille University, 13009 Marseille, France.
Cancers (Basel). 2024 Mar 19;16(6):1198. doi: 10.3390/cancers16061198.
An incidental axillary dose of adjuvant radiotherapy using tangential beams is usually given after breast-conserving surgery for breast cancer. The goal of this sub-study was to evaluate this incidental dose in the setting of post-mastectomy radiotherapy (PMRT) according to two different radiotherapy techniques.
Patients participating in a randomized SERC trial who received PMRT in a single center were included. We collected the incidental axillary dose delivered to the Berg level 1 using different dosimetric parameters and compared two techniques using Student's -test: three-dimensional conformal radiotherapy (3D-CRT) and volumetric arc therapy (VMAT).
We analyzed radiotherapy plans from 52 patients who received PMRT from 2012 to 2021. The mean dose delivered to the Berg level 1 was 37.2 Gy. It was significantly higher with VMAT than with 3D-CRT-43.6 Gy (SD = 3.1 Gy) versus 34.8 Gy (SD = 8.6 Gy) < 0.001. Eighty-four percent of the Berg level 1 was covered by 40 Gy isodose in the VMAT group versus 55.5% in the 3D-CRT group < 0.001.
On the Berg level 1, PMRT gives a dose at least equivalent to the one given by post-breast-conserving surgery radiotherapy, making it possible to limit completion axillary lymph node dissections in select pN1a patients treated with a mastectomy. Modern radiotherapy techniques like VMAT tend to increase this incidental dose.
乳腺癌保乳手术后通常会使用切线野对腋窝进行辅助放疗。本亚研究的目的是根据两种不同的放疗技术评估乳房切除术后放疗（PMRT）时的这种附带剂量。
纳入参与一项单中心随机SERC试验且接受PMRT的患者。我们收集了使用不同剂量学参数传递至伯格1级的附带腋窝剂量，并使用学生t检验比较了两种技术：三维适形放疗（3D-CRT）和容积弧形调强放疗（VMAT）。
我们分析了2012年至2021年接受PMRT的52例患者的放疗计划。传递至伯格1级的平均剂量为37.2 Gy。VMAT组的剂量显著高于3D-CRT组——分别为43.6 Gy（标准差=3.1 Gy）和34.8 Gy（标准差=8.6 Gy），P<0.001。VMAT组中84%的伯格1级被40 Gy等剂量线覆盖，而3D-CRT组为55.5%，P<0.001。
在伯格1级，PMRT给予的剂量至少等同于保乳手术后放疗的剂量，这使得在接受乳房切除术的特定pN1a患者中有可能限制腋窝淋巴结清扫术的完成。像VMAT这样的现代放疗技术往往会增加这种附带剂量。
