Casale Michelina, Draghini Lorena, Trippa Fabio, Costantini Sara, Vicenzi Lisa, Tesei Letizia, Di Marzo Alessandro, Arcidiacono Fabio, Italiani Marco, Maranzano Ernesto
Radiotherapy Oncology Centre, Santa Maria Hospital, Terni, Italy.
Radiation Oncology Centre, Ospedali Riuniti Umberto I, Ancona, Italy.
J Contemp Brachytherapy. 2022 Oct;14(5):470-475. doi: 10.5114/jcb.2022.121175. Epub 2022 Nov 15.
To evaluate the reliability of algebraic sum with respect to rigid fusion of treatment plans related to adjuvant external beam pelvic radiotherapy (APR) and vaginal cuff high-dose-rate brachytherapy (BT) in uterine cancer patients.
For algebraic sum, APR and BT doses were mathematically added. Rigid fusion was realized overlapping computed tomography (CT) images of APR and BT treatment plans. Rectum and bladder were considered reference organs at risk (OARs). Following dose (D) parameters were examined: D (0.5 cc), D and D for rectum, D (0.5 cc) and D for bladder; for each parameter, differences between the two adopted methods were reported as Δ-values.
Twenty uterine cancer patients submitted to radical surgery followed by APR plus vaginal cuff BT were reviewed. APR was done with a dose of 25 × 2 Gy. All patients also receveid a vaginal cuff boost with BT at the dose of 2 × 5 Gy. Differences between mean cumulative doses calculated with rigid fusion and algebraic sum were evaluated. For the rectum and bladder ΔD, there were no significant differences, and BT contribution resulted minimal. An apparent significant difference value was registered in bladder ΔD (0.5 cc). No toxicity was observed.
In uterine cancer patients submitted to APR and vaginal cuff BT, algebraic sum and rigid plan fusion of doses allowed to obtain similar results in evaluating cumulative OARs' doses. Further investigations and increased number of patients are recommended to confirm our findings.
评估代数和在子宫癌患者辅助性盆腔外照射放疗（APR）及阴道残端高剂量率近距离放疗（BT）治疗计划刚性融合方面的可靠性。
对于代数和，将APR和BT剂量进行数学相加。通过重叠APR和BT治疗计划的计算机断层扫描（CT）图像实现刚性融合。将直肠和膀胱视为参考危及器官（OARs）。检查以下剂量（D）参数：直肠的D（0.5 cc）、D及D，膀胱的D（0.5 cc）和D；对于每个参数，将两种采用方法之间的差异报告为Δ值。
回顾了20例接受根治性手术，随后进行APR加阴道残端BT的子宫癌患者。APR剂量为25×2 Gy。所有患者还接受了剂量为2×5 Gy的阴道残端BT增敏。评估了用刚性融合和代数和计算的平均累积剂量之间的差异。对于直肠和膀胱的ΔD，无显著差异，且BT的贡献极小。膀胱ΔD（0.5 cc）出现明显的显著差异值。未观察到毒性反应。
在接受APR和阴道残端BT的子宫癌患者中，剂量的代数和与刚性计划融合在评估累积OARs剂量方面能获得相似结果。建议进一步研究并增加患者数量以证实我们的发现。
