Mondragon Lorena Lio, Lopez Hidralba Pérez, Diaz Adolfo Fernández, Lio Iván Avilés, Guzman Alejandro Olmos
Department of Radiotherapy, National Medical Center XXI Century, Instituto Mexicano del Seguro Social, México City, México.
Department of Radiotherapy, National Medical Center of Bajío, Instituto Mexicano del Seguro Social, León, Guanajuato, México.
Rep Pract Oncol Radiother. 2023 Aug 28;28(4):478-484. doi: 10.5603/RPOR.a2023.0053. eCollection 2023.
The knowledge of the risks induced by radiation with hypofractionation regimens has only recently been estimated together with its implementation as a management standard. However, the dose to other risk organs with intensity-modulated radiation therapy (IMRT) or volumetric modulated arc therapy (VMAT) is not clear, that is why this is only a reference study of radiation doses to organs at risk in hypofractionation in our center.
We completed a retrospective and observational analysis of 1398 patients treated with adjuvant hypofractionated radiotherapy from 2015 to 2018, using the clinical records and dose-volume histogram of patients treated with moderate hypofractionated adjuvant radiotherapy. To analyze the institutional experience on the dosimetry of the esophagus and liver as risk organs in the use of moderate adjuvant hypofractionated radiotherapy in breast cancer.
The dosimetry of the esophagus was 3271 cGy DMax, 177 cGy DMed, 68 cGy D50%, 500 cGy DcMAX with 3D RT and 4124 cGy DMax, 1242 cGy DMed, 934.50 cGy D50%, 3213 cGy DcMAX with IMRT/VMAT and the dosimetry for the liver was for right breast cancer 466 cGy DMed, 102 cGy D50% and 8% V20, for left breast cancer 22 cGy DMed, 6.10 cGy D50% and 0.3% V20.
The statistically significant differences in irradiation show the lack of consensus on the optimal restrictions in hypofractionation regimens to reduce clinical sequela; consequently, the variability in the specification of each radiation oncologist is observed; standardization in our center can lead to improvement in the quality of treatments.
关于大分割放疗方案所致风险的认识直到最近才与作为一种治疗标准的实施情况一同得到评估。然而，调强放射治疗（IMRT）或容积调强弧形治疗（VMAT）时其他危险器官所接受的剂量尚不清楚，这就是为什么这只是我们中心大分割放疗中危险器官辐射剂量的一项参考研究。
我们利用接受中度大分割辅助放疗患者的临床记录和剂量体积直方图，对2015年至2018年接受辅助大分割放疗的1398例患者进行了回顾性观察分析。旨在分析在乳腺癌中度辅助大分割放疗中，将食管和肝脏作为危险器官进行剂量测定的机构经验。
食管的剂量测定结果为，三维适形放疗（3D RT）时DMax为3271 cGy、DMed为177 cGy、D50%为68 cGy、DcMAX为500 cGy，IMRT/VMAT时DMax为4124 cGy、DMed为1242 cGy、D50%为934.50 cGy、DcMAX为3213 cGy；肝脏的剂量测定结果为，右乳癌时DMed为466 cGy、D50%为102 cGy、V20为8%，左乳癌时DMed为22 cGy、D50%为6.10 cGy、V20为0.3%。
照射方面具有统计学意义的差异表明，在大分割放疗方案以减少临床后遗症的最佳限制方面缺乏共识；因此，可以观察到每位放射肿瘤学家的规范存在差异；我们中心的标准化可提高治疗质量。
