中国癌症杂志 ›› 2020, Vol. 30 ›› Issue (8): 611-619.doi: 10.19401/j.cnki.1007-3639.2020.08.008

• 论著 • 上一篇    下一篇

三种全乳同步瘤床加量调强放疗计划的比较

陈 刚,张顺康,沈 磊,孙丽云,赵映薇,王 鑫,王欢欢,卢 月   

  1. 上海交通大学医学院附属第九人民医院黄浦分院放疗科,上海 200011
  • 出版日期:2020-08-30 发布日期:2020-09-03
  • 通信作者: 卢 月 E-mail: 3554050@qq.com
  • 基金资助:
    上海市黄浦区医疗卫生重点研究发展专科课题计划(HWZFK201804-1)。

Comparison of three types of intensity-modulated radiotherapy plans for adjuvant whole breast and simultaneous tumor bed boost radiotherapy

CHEN Gang, ZHANG Shunkang, SHEN Lei, SUN Liyun, ZHAO Yingwei, WANG Xin, WANG Huanhuan, LU Yue   

  1. Department of Radiation Oncology, Shanghai Jiao Tong University Medical School Affiliated Ninth People’s Hospital Huangpu Branch, Shanghai 200011, China
  • Published:2020-08-30 Online:2020-09-03
  • Contact: LU Yue E-mail: 3554050@qq.com

摘要: 背景与目的:目前保乳手术+术后放疗已成为早期乳腺癌标准治疗模式。采用3种不同适形调强放疗技术制定早期乳腺癌保乳术后全乳同步瘤床加量的放疗计划,并对3种放疗计划的肿瘤靶区、危及器官剂量学参数等方面进行比较。方法:随机选取上海交通大学医学院附属第九人民医院黄浦分院放疗科2018年度收治的女性乳腺癌保乳术后患者50例,左、右侧乳腺癌患者各25例。分别采用正向调强、逆向调强、容积调强等3种调强治疗方法制定全乳同步瘤床加量放疗计划。比较3种放疗计划的靶区适形度(conformity index,CI)与均匀度(homogeneity index,HI);危及器官的剂量学参数,包括同侧肺(V 5V 20V 30 )、心脏(D mean 、左乳癌V 25 、右乳癌V 15 )、对侧乳腺(D 2D mean );单次治疗的总跳数(minute,MU)及出束时间,并进一步分析乳房体积大小对放疗计划的影响。结果:正向调强、逆向调强与容积调强放疗计划的全乳靶区CI分别为0.69±0.09、0.86±0.06和0.79±0.07(两两比较P<0.001),瘤床靶区CI分别为0.71±0.15、0.79±0.15和0.80±0.12(两两比较P=0.007、P<0.001和P=0.624),全乳靶区HI分别为0.17±0.03、0.13±0.03和0.18±0.03(两两比较P<0.001),瘤床靶区HI分别为0.17±0.05、0.07±0.01和0.10±0.02(两两比较P<0.001)。同侧肺V 5 为56.08±7.24、46.08±5.48和57.82±6.64(两两比较P<0.001、P=0.079、P<0.001),V 20 为27.96±2.57、20.28±2.13和23.44±2.71(两两比较P<0.001、P=0.025、P<0.001),V 30 为22.34±2.20、15.40±2.37和16.42±2.82(两两比较P<0.001、P=0.006、P=0.012)。左乳癌心脏D mean 为775.48±113.23、584.20±223.04和634.24±174.38(两两比较P<0.001、P<0.001、P=0.045),右乳癌心脏D mean 为209.32±84.60、125.56±41.65和200.80±49.74(两两比较P<0.001、P=0.524、P<0.001),左乳癌心脏V 25 为8.20±1.73、5.02±1.38和6.65±1.56(两两比较P<0.001、P<0.001、P=0.037),右乳癌心脏V 15 均为0值不做比较。对侧乳腺的D mean 为288.05±105.14、108.25±56.47和123.59±73.79(两两比较P<0.001、P<0.001、P=0.023)。单次治疗MU为285.74±17.73、1463.94±227.74和445.50±98.22(两两比较P<0.001),出束时间为205.12±20.68、343.26±37.59和138.06±13.53(两两比较P<0.001)。50例患者以患侧乳房体积平均值764.89 mL为界分成两组,乳房小体积组3种放疗计划的靶区CI、HI以及单次MU与出束时间优于乳房大体积组,而在正常器官剂量学方面两组间差异无统计学意义。结论:逆向调强与容积调强在靶区剂量学参数及危及器官的保护方面优于正向调强计划。其中逆向调强计划稍优于容积调强,推荐用于耐受较好、有长期生存预期的中、青年患者;而容积调强计划的单次MU更少,出束时间更短,建议老年、乳房体积较大的患者采用。

关键词: 早期乳腺癌, 同步瘤床加量, 调强放疗

Abstract: Background and purpose: Breast-conserving surgery (BCS) plus post-operative radiation therapy has become the standard of care for early stage breast cancer. This study aimed to design whole breast and simultaneous tumor bed boost radiation therapy plans by adopting 3 different types of intensity-modulated radiation therapy (IMRT) techniques, and to compare the dosimetric parameters involving target volumes, organs at risk (OARs) and other aspects of the three IMRT plans. Methods: Fifty female patients with early stage breast cancer (25 left and 25 right, respectively) treated with BCS during the year of 2018 in Department of Radiation Oncology, Shanghai Jiao Tong University Medical School Affiliated Ninth People’s Hospital Huangpu Branch, were randomly selected. Adjuvant whole breast and simultaneous tumor bed boost radiation therapy plans were designed by adopting forward-planned IMRT, reverse-planned IMRT and volumetric modulated arc therapy (VMAT) techniques. Conformity index (CI) and homogeneity index (HI) of target volumes, dosimetric parameters of OARs, including ipsilateral lung (V 5 , V 20 , V 30 ), heart (D mean , V 25 for left breast cancer, V 15 ), contralateral breast (D 2 , D mean ), single fraction minute (MU) and beam-out time of the three IMRT plans were compared, respectively. Further analysis was made to identify the effect of breast volume on IMRT plans. Results: CI of forward-planned IMRT, reverse-planned IMRT and VMAT for whole breast target volume were 0.69±0.09, 0.86±0.06, 0.79±0.07, respectively (pairwise comparison P<0.001). CI for tumor bed target volume were 0.71±0.15, 0.79±0.15 and 0.80±0.12, respectively (pairwise comparison, P=0007, P<0.001, P=0.624, respectively). HI of the three plans for whole breast target volume were 0.17±0.03, 0.13±0.03 and 0.18±0.03, respectively (pairwise comparison, P<0.001). HI for tumor bed target volume were 0.17±0.05, 0.07±0.01 and 0.10±0.02, respectively (pairwise comparison, P<0.001). Ipsilateral lung V 5 was 56.08±7.24, 46.08±5.48 and 57.82±6.64, respectively (pairwise comparison, P<0.001, P=0.079, P<0.001, respectively). V 20 was 27.96±2.57, 20.28±2.13 and 23.44±2.71, respectively (pairwise comparison, P<0.001, P=0.025, P<0.001, respectively). V 30 was 22.34±2.20, 15.40±2.37 and 16.42±2.82, respectively (pairwise comparison, P<0.001, P=0.006, P<0.012, respectively). Heart D mean for left breast cancer was 775.48±113.23, 584.20±223.04 and 634.24±174.38, respectively (pairwise comparison, P<0.001, P<0.001, P=0.045, respectively). Heart D mean for right breast cancer was 209.32±84.60, 125.56±41.65 and 200.80±49.74, respectively (pairwise comparison, P<0.001, P=0.524, P<0.001, respectively). Heart V 25 for left breast cancer was 8.20±1.73, 5.02±1.38 and 6.65±1.56, respectively (pairwise comparison, P<0.001, P<0.001, P=0.037, respectively). Heart V 15 for right breast cancer was 0 for all, and no further comparison was made. Contralateral breast D mean was 288.05±105.14, 108.25±56.47 and 123.59±73.79, respectively (pairwise comparison, P<0.001, P<0.001, P=0.023, respectively). Single fraction MU was 285.74±17.73, 1463.94±227.74 and 445.50±98.22, respectively (pairwise comparison, P<0.001). Beam-out time was 205.12±20.68, 343.26±37.59 and 138.06±13.53, respectively (pairwise comparison, P<0.001). A total of 50 patients were divided into small/large breast volume groups according to the mean breast volume (764.89 mL). Better dosimetric parameters of target volumes, fewer single fraction MUs and shorter beam-out time were found in small volume group. No statistical difference in OARs’ dosimetric parameters was found in the two groups. Conclusion: Reverse-planned IMRT and VMAT were better than forward-planned IMRT in the aspects of target volumes’ dosimetric parameters and protection of OARs. Reverse-planned IMRT was slightly superior to VMAT, and was recommended for younger patients with better tolerability and longer life expectancy. VMAT had both fewer single fraction MUs and shorter beam-out time, and was preferable for patients with older age and larger breast volume.

Key words: Early stage breast cancer, Simultaneous tumor bed boost, Intensity-modulated radiotherapy