左乳腺癌改良根治术后胸壁电子线照射、X线调强照射、X线和电子线混合调强照射的临床剂量学研究

发布时间：2018-03-22 21:07

本文选题：乳腺癌　切入点：改良根治术　出处：《昆明医科大学》2017年硕士论文　论文类型：学位论文

【摘要】：[目的]:研究比较左乳腺癌改良根治术后胸壁电子线照射、X线调强照射、X线和电子线混合调强照射三种放疗计划的剂量学特点。[方法]:选取2014年12月至2015年9月昆明医科大学第三附属医院收治的女性中晚期左侧乳腺癌改良根治术后患者16例,左胸壁表面垫5mm厚度的等效填充物,用热塑体膜固定后行CT定位,用Pinnacle39.10三维调强治疗计划系统对每位患者分别设计三种胸壁放射治疗计划:电子线照射计划(E计划)、X线调强照射计划(IMRT计划)、X线和电子线混合调强照射计划(IMRT+E计划),并对三种计划靶区和危及器官的剂量学参数进行评估和比较。[结果]:1.靶区剂量学比较结果:三种计划所有靶区剂量学参数的组间比较,差异均有统计学意义(P0.05);靶区适形指数CI: IMRT+E计划最好,E计划最差;IMRT+E计划与E计划、IMRT计划之间的两两比较差异有统计学意义(P0.05);靶区均匀性指数HI: IMRT计划最好,E计划值最差;E计划与IMRT计划、IMRT+E计划之间的两两比较差异均有统计学意义(P0.05);机器跳数MU: E计划出束时间最短,IMRT+E计划时间最长,差异有统计学意义(P0.05)。2.危及器官剂量学比较结果:(1)危及器官肺:三组计划左肺的Vs、V10、右肺Dmean等参数的组间比较差异有统计学意义(P0.05) , E计划最小,IMRT+E计划最大,E计划优于IMRT+E计划和IMRT计划,尤其对于左肺V5及右肺Dmean差异显著(P0.05);左肺V20: IMRT计划最小,E计划最大;IMRT计划明显优于E计划和IMRT+E计划(P0.05);全肺Dmean、V20: IMRT计划最小,差异均没有统计学意义(P0.05)。(2)危及器官心脏:V10、Dmean: E计划值最低,IMRT+E计划值最高;E计划明显优于IMRT计划和IMRT+E计划(P0.05) ; V30: E计划值最低,IMRT计划值最高;E计划明显优于IMRT计划(P0.05)。(3)右乳Dmean:E计划要优于IMRT计划值和IMRT+E计划,差异有统计学意义(P0.05);脊髓Dmax: IMRT计划最低,IMRT+E计划最高,均在限定范围内。[结论]:E计划靶区的均匀性和适形度最差,但对左肺的低剂量体积、心脏及对侧乳腺的保护上优于IMRT计划和IMRT+E计划;IMRT计划靶区分布最均匀,适形度也较好,但增加了心脏及肺的低剂量受照体积,在危及器官的保护上存在不足;IMRT+E计划在整体的靶区分布上表现最好,体现出明显优势,但是在危及器官的保护上表现最差,且治疗时间最长、操作复杂。乳腺癌改良术后胸壁放疗应根据患者自身胸壁轮廓、胸壁厚度不同,选择合适的射线种类、能量、等效填充物的厚度以及放疗技术制定出个性化放疗方案。
[Abstract]:[objective]: to compare the dosimetric characteristics of three radiotherapy plans of chest wall electron ray irradiation after modified radical mastectomy for left breast cancer. [methods] from December 2014 to September 2015, three radiotherapy plans, intensity modulated X-ray and mixed intensity modulated electron irradiation, were compared. Sixteen female patients after modified radical mastectomy for middle and late stage breast cancer were treated in the third affiliated Hospital of Kunming Medical University. The 5mm thickness of the left chest surface pad was fixed with thermoplastic membrane and then fixed with CT. Three kinds of chest wall radiotherapy plans were designed for each patient by using the Pinnacle39.10 three dimensional intensity modulated treatment plan system: electron ray radiation plan E plan X ray intensity modulated radiation plan / IMRT plan and mixed intensity modulated X-ray radiation plan / IMRT E meter. The dosimetric parameters of the three planned target areas and organ hazards were evaluated and compared. [results] 1.The dosimetry comparison of the target areas: comparison of dosimetry parameters of all target areas in the three plans, The difference was statistically significant (P 0.05); the target area conformability index (CI) was the best in IMRT E plan and the worst in E plan. There was a significant difference between IMRT E plan and E plan (P 0.05); the target area uniformity index (HI): IMRT plan was the best one. There were statistically significant differences between the worst plan and IMRT plan (P 0.05), and the shortest beam time of plan MUE was the shortest time of plan IMRT E, and the time of plan IMRT E was the longest. The difference was statistically significant (P 0.05. 2.The results of endangering organ dosimetry: 1) endangering organ lung: the difference between three groups of parameters such as Vslr V10 of left lung and Dmean of right lung was statistically significant (P0.05), and the minimum of plan E was the maximum of IMRTE plan (P0.05), and the difference was significant (P0.05) between the three groups in the parameters of left lung, right lung, etc. (P < 0.05). Better than the IMRT E and IMRT plans, Especially for the left lung V5 and the right lung Dmean, the left lung V20: IMRT plan, the minimum E plan and the maximum IMRT plan were significantly superior to the E plan and the IMRT E plan, and the whole lung Dmean V20: IMRT plan was the smallest, especially for the left lung V5 and the right lung. No significant difference was found between the two groups (P < 0.05, P < 0.05, P = 0. 05)) the lowest Dmean: e plan value was lower than IMRT plan and IMRT E plan (P 0. 05), and V30: e plan value was lower than that of IMRT plan, and the lowest value of V30: e plan was significantly better than that of IMRT plan (P < 0. 05), and the lowest value of V30: e plan was higher than that of IMRT E plan (P < 0. 05). The right breast Dmean:E plan was superior to IMRT plan value and IMRT E plan. The difference was statistically significant (P 0.05), spinal cord Dmax: IMRT was the lowest and IMRT E was the highest, all of them were within a limited range. [conclusion] the uniformity and conformability of the target area of Plan E was the worst, but the low dose volume of left lung was the lowest. The protection of heart and contralateral mammary gland was better than that of IMRT and IMRT E plan. The distribution of target area was the most uniform and the conformal degree was better, but the low dose radiation volume of heart and lung was increased. In the aspect of organ protection, IMRT E has the best performance in the overall target area distribution, showing obvious advantages, but the worst performance in organ protection, and the longest treatment time. The operation is complicated. According to the profile of the chest wall and the thickness of the chest wall, we should choose the appropriate radiation type, energy, the thickness of the equivalent fillers and the radiotherapy technology to make the individualized radiotherapy plan according to the breast cancer modified postoperative chest wall radiotherapy.
【学位授予单位】：昆明医科大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R737.9

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