Ślosarek Krzysztof, Osewski Wojciech, Grządziel Aleksandra, Radwan Michał, Dolla Łukasz, Szlag Marta, Stąpór-Fudzińska Małgorzata
MSC Memorial Cancer Center and Institute of Oncology Gliwice Branch, Department of Radiotherapy and Brachytherapy Planning, ul. Wybrzeża Armii Krajowej 15, 44-101 Gliwice, Poland.
MSC Memorial Cancer Center and Institute of Oncology Gliwice Branch, Radiotherapy Department, ul. Wybrzeża Armii Krajowej 15, 44-101 Gliwice, Poland.
Rep Pract Oncol Radiother. 2014 Nov 18;20(2):99-103. doi: 10.1016/j.rpor.2014.10.010. eCollection 2015 Mar-Apr.
Comparisons of integral dose delivered to the treatment planning volume and to the whole patient body during stereotactic, helical and intensity modulated radiotherapy of prostate.
Multifield techniques produce large volumes of low dose inside the patient body. Delivered dose could be the result of the cytotoxic injuries of the cells even away from the treatment field. We calculated the total dose absorbed in the patient body for four radiotherapy techniques to investigate whether some methods have a potential to reduce the exposure to the patient.
We analyzed CyberKnife plans for 10 patients with localized prostate cancer. Five alternative plans for each patient were calculated with the VMAT, IMRT and TomoTherapy techniques. Alternative dose distributions were calculated to achieve the same coverage for PTV. Integral Dose formula was used to calculate the total dose delivered to the PTV and whole patient body.
Analysis showed that the same amount of dose was deposited to the treated volume despite different methods of treatment delivery. The mean values of total dose delivered to the whole patient body differed significantly for each treatment technique. The highest integral dose in the patient's body was at the TomoTherapy and CyberKnife treatment session. VMAT was characterized by the lowest integral dose deposited in the patient body.
The highest total dose absorbed in normal tissue was observed with the use of a robotic radiosurgery system and TomoTherapy. These results demonstrate that the exposure of healthy tissue is a dosimetric factor which differentiates the dose delivery methods.
比较前列腺立体定向放疗、螺旋断层放疗和调强放疗期间治疗计划靶区及患者全身所接受的积分剂量。
多野技术会在患者体内产生大量低剂量区域。即使远离治疗区域，所给予的剂量也可能导致细胞发生细胞毒性损伤。我们计算了四种放疗技术中患者全身吸收的总剂量，以研究某些方法是否有可能减少患者所受照射。
我们分析了10例局限性前列腺癌患者的射波刀治疗计划。对每位患者分别用容积调强弧形放疗（VMAT）、调强放疗（IMRT）和螺旋断层放疗技术计算了五种替代计划。计算替代剂量分布以实现对计划靶区相同的覆盖范围。使用积分剂量公式计算给予计划靶区和患者全身的总剂量。
分析表明，尽管采用了不同的治疗方式，但给予治疗靶区的剂量相同。每种治疗技术中给予患者全身的总剂量平均值差异显著。患者体内最高的积分剂量出现在螺旋断层放疗和射波刀治疗过程中。VMAT的特点是患者体内沉积的积分剂量最低。
使用机器人放射外科系统和螺旋断层放疗时，观察到正常组织吸收的总剂量最高。这些结果表明，健康组织的受照情况是区分剂量给予方式的一个剂量学因素。
