Jodda Agata, Urbański Bartosz, Piotrowski Tomasz, Malicki Julian
Department of Medical Physics, Greater Poland Cancer Centre, Poznań, Poland.
Department of Electroradiology, Poznań University of Medical Sciences, Poznań, Poland; Gynaecological Radiotherapy Ward, Greater Poland Cancer Centre, Poznań, Poland.
Phys Med. 2017 Apr;36:54-59. doi: 10.1016/j.ejmp.2017.03.006. Epub 2017 Mar 21.
To compare normal tissue complication probability (NTCP) and average doses in the bone marrow (BM), obtained for five different radiotherapy delivery and planning strategies of cervical and endometrial cancer.
MATERIAL/METHODS: 50 patients were taken to analysis. For each case, 3 different dose delivery techniques were used: 4-field, X15MV, 3DCRT; 7-field, X6MV, IMRT; and 2-arc, X6MV, VMAT. Two optimization scenarios were used for the IMRT and VMAT plans generation: with (+) and without (-) the inclusion of the BM as an optimized structure. Average doses and dose-volume histogram parameters for the PTV, BM, bladder, rectum, bowels and femoral heads were compared. In addition, the BM doses were analyzed with respect to the PTV and/or volume of the BM, and NTCP for the BM were computed.
The dose in PTV for evaluated plans was similar. The worst doses in organs at risk were obtained for 3DCRT. Using the BM during the optimization of IMRT and VMAT reduces an average dose in BM without increasing the doses in the bladder, rectum and bowels. Differences between doses in BM for IMRT(+) and VMAT(+) plans were similar while NTCP was lower for VMAT(+). A correlation between average dose in BM and the volume ratio of BM and PTV was found for each technique.
Using the BM during the optimization of the IMRT and VMAT plans effectively reduces the dose in BM without increasing the dose in the bladder, rectum and bowels. The VMAT(+) plans were characterized by the lowest NTCP.
比较五种不同的宫颈癌和子宫内膜癌放射治疗方案及计划中正常组织并发症概率（NTCP）和骨髓（BM）平均剂量。
材料/方法：选取50例患者进行分析。对每个病例使用3种不同的剂量递送技术：4野、15MV X射线、三维适形放疗（3DCRT）；7野、6MV X射线、调强放疗（IMRT）；以及2弧、6MV X射线、容积调强弧形放疗（VMAT）。在IMRT和VMAT计划生成中使用两种优化方案：将骨髓作为优化结构（+）和不将骨髓作为优化结构（-）。比较了计划靶体积（PTV）、骨髓（BM）、膀胱、直肠、肠道和股骨头的平均剂量及剂量体积直方图参数。此外，分析了骨髓剂量与PTV和/或骨髓体积的关系，并计算了骨髓的NTCP。
评估计划中PTV的剂量相似。3DCRT在危及器官中产生的剂量最差。在IMRT和VMAT优化过程中使用骨髓可降低骨髓平均剂量，而不增加膀胱、直肠和肠道的剂量。IMRT（+）和VMAT（+）计划中骨髓剂量的差异相似，而VMAT（+）的NTCP较低。每种技术的骨髓平均剂量与骨髓和PTV的体积比之间均存在相关性。
在IMRT和VMAT计划优化过程中使用骨髓可有效降低骨髓剂量，而不增加膀胱、直肠和肠道的剂量。VMAT（+）计划的NTCP最低。
