Wang Guangyu, Wang Zhiqun, Zhang Yu, Sun Xiansong, Sun Yuliang, Guo Yuping, Zeng Zheng, Zhou Bing, Hu Ke, Qiu Jie, Yan Junfang, Zhang Fuquan
Department of Radiation Oncology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, China.
Tumor Hospital affiliated to Xinjiang Medical University, Urumqi, China.
Adv Radiat Oncol. 2024 Apr 13;9(7):101510. doi: 10.1016/j.adro.2024.101510. eCollection 2024 Jul.
This study evaluated the first clinical implementation of daily iterative cone beam computed tomography (iCBCT)-guided online adaptive radiation therapy (oART) in the postoperative treatment of endometrial and cervical cancer.
Seventeen consecutive patients treated with daily iCBCT-guided oART were enrolled in this prospective study, with a reduced uniform 3-dimensional PTV margin of 5 mm. Treatment plans were designed to deliver 45 or 50.4 Gy in 1.8 Gy daily fractions to PTV. Pre- and posttreatment ultrasound and iCBCT scans were performed to record intrafractional bladder and rectal volume changes. The accuracy of contouring, oART procedure time, dosimetric outcomes, and acute toxicity were evaluated.
The average time from first iCBCT acquisition to completion of treatment was 22 minutes and 26 seconds. During this period, bladder volume increased by 44 cm using iCBCT contouring, whereas rectal volume remained stable (62.9 cm pretreatment vs 61.9 cm posttreatment). A total of 91.6% of influencers and 88.1% of CTVs required no or minor edits. The adapted plan was selected in all (434) fractions and significantly improved the dosimetry coverage for CTV and PTV, especially the vaginal PTV coverage by nearly 7% ( < .05). The adapted bladder D was 104.61 cGy, and the rectum D was 123.67 cGy, significantly lower than the scheduled plan of 108.24 and 128.19 cGy, respectively. The bone marrow and femur head left and right dosimetry were also improved with adaptation. Grade 2 acute gastrointestinal and genitourinary toxicities were 24% and 0, respectively. There was a grade 3 acute toxicity of decreased white blood cell count in 1 patient.
Daily oART was associated with favorable dosimetry improvement and low acute toxicity, supporting its safety and efficacy for postoperative treatment of endometrial and cervical cancer. These results need to be validated in a larger prospective randomized controlled cohort.
本研究评估了每日迭代锥形束计算机断层扫描（iCBCT）引导下的在线自适应放射治疗（oART）在子宫内膜癌和宫颈癌术后治疗中的首次临床应用。
本前瞻性研究纳入了17例接受每日iCBCT引导下oART治疗的连续患者，将均匀的三维计划靶体积（PTV）边界缩小至5 mm。治疗计划设计为以每日1.8 Gy的分次剂量向PTV给予45或50.4 Gy。治疗前和治疗后的超声及iCBCT扫描用于记录分次治疗期间膀胱和直肠体积的变化。评估了轮廓勾画的准确性、oART程序时间、剂量学结果和急性毒性。
从首次采集iCBCT到完成治疗的平均时间为22分26秒。在此期间，使用iCBCT轮廓勾画时膀胱体积增加了44 cm³，而直肠体积保持稳定（治疗前62.9 cm³ vs 治疗后61.9 cm³）。总共91.6%的危及器官（OAR）和88.1%的临床靶体积（CTV）无需编辑或只需进行少量编辑。在所有（434）分次中均选择了调整后的计划，该计划显著改善了CTV和PTV的剂量学覆盖，尤其是阴道PTV的覆盖，提高了近7%（P <.05）。调整后的膀胱D为104.61 cGy，直肠D为123.67 cGy，显著低于计划剂量的108.24和128.19 cGy。骨髓以及左右股骨头的剂量学也因调整而得到改善。2级急性胃肠道和泌尿生殖系统毒性分别为24%和0。1例患者出现3级急性毒性，表现为白细胞计数下降。
每日oART与良好的剂量学改善和低急性毒性相关，支持其在子宫内膜癌和宫颈癌术后治疗中的安全性和有效性。这些结果需要在更大规模的前瞻性随机对照队列中进行验证。
