双侧乳腺癌保乳术后螺旋断层调强放射治疗与容积旋转调强放射治疗的剂量学比较  

Dosimetric comparison of helical tomotherapy and volumetric modulated arc therapy for bilateral breast cancer after breast-conserving surgery

作　　者：刘旭红 夏耀雄 陈晓[1] 赵永军 王禅 LIU Xu-hong;XIA Yao-xiong;CHEN Xiao;ZHAO Yong-jun;WANG Chan(Department of Radiotherapy,Peking University Cancer Hospital Yunnan·Yunnan Cancer Hospital·The Third Affiliated Hospital of Kunming Medical University,Kunming650118,Yunnan,China)

机构地区：[1]北京大学肿瘤医院云南医院·云南省肿瘤医院·昆明医科大学第三附属医院放疗科,云南昆明650118

出　　处：《生物医学工程与临床》2024年第5期634-640,共7页Biomedical Engineering and Clinical Medicine

摘　　要：目的研究双侧乳腺癌保乳术后采用螺旋断层调强放射治疗(HT)与容积旋转调强放射治疗(VMAT)在计划靶区(PTV)和危及器官(OAR)的剂量学差异。方法选择云南省肿瘤医院2018年6月至2022年6月行保乳术后放射治疗的双侧早期原发性乳腺癌患者15例,均为女性,年龄34~65岁,中位年龄52岁;病理分期均为T1N0M0。采用Accuray公司螺旋断层放射治疗计划系统和Elekta公司Monaco计划系统分别为同一例患者设计HT和VMAT计划,两种放射治疗双侧乳腺癌双靶区处方剂量均给予50 Gy/25次。对HT和VMAT计划在PTV和OAR剂量学参数的差异进行统计学分析。结果HT和VMAT计划的PTV剂量均能满足临床要求,HT的覆盖度(D95%)高于VMAT计划,HT的均匀性指数(HI)从VMAT计划的0.113降到了0.068(P<0.001),HT的D_(max)明显低于VMAT计划[(54.14±0.70)Gy vs(56.27±0.81)Gy。P<0.001],适形性指数(CI)两种计划相比,差异无统计学意义(P>0.05)。在OAR方面,HT的脊髓D_(max)、全肺V5和心脏V5明显低于VMAT计划[(3.44±0.42)Gy vs(5.62±0.34)Gy,(39.65±4.40)%vs(52.73±2.50)%,(15.88±2.09)%vs(40.28±1.47)%。P<0.05],但HT全肺、心脏和肝脏的V20和V30及肝脏D_(mean)明显高于VMAT计划(P<0.05),全肺D_(mean)和心脏D_(mean)两种计划相比,差异无统计学意义(P>0.05)。VMAT计划比HT计划的治疗时间稍长[(886.67±38.09)s vs(843.67±21.61)s。P=0.013]。结论两种计划均能满足临床治疗要求。HT的PTV剂量学参数优于VMAT计划,对脊髓的保护更好,并明显降低了肺、心脏的低剂量区体积,但HT在肺、心脏和肝脏的中、高剂量区受照体积明显高于VMAT计划。HT治疗效率稍高。Objective To study the dosimetric difference between helical tomotherapy(HT)and volumetric modulated arc therapy(VMAT)in planning target volume(PTV)and organ at risk(OAR)for bilateral breast cancer after breast-conserving surgery.Methods From June 2018 to June 2022,a total of 15 female patients with bilateral early primary breast cancer who underwent radiotherapy after breast-conserving surgery were enrolled,which aged 34-65 years old with median age of 52 years old;pathological stage was T1N0M0.The HT plan system(Accuray Company)and Monaco planning system(Elekta Company)were used to design HT and VMAT plans for the same patient,respectively.The prescribed dose of two kinds of treatment for bilateral breast cancer was 50 Gy/25f in double target area.The differences in dosemetry parameters of PTV and OAR between HT and VMAT plans were statistically analyzed.Results For PTV,the target doses of the two plans met the clinical requirements.The coverage(D95%)of HT plan was higher than that of VMAT plan.The homogeneity index(HI)of HT decreased from 0.113 to 0.068(P<0.001),and D_(max)of HT was significantly lower than that of VMAT plan[(54.14±0.70)Gy vs(56.27±0.81)Gy.P<0.001].There was no significant difference in conformity index(CI)between 2 plans(P>0.05).For OAR,the spinal cord D_(max)and whole lungs V5 and heart V5 of HT plan were significantly lower than those of VMAT plan[(3.44±0.42)Gy vs(5.62±0.34)Gy,(39.65±4.40)%vs(52.73±2.50)%,(15.88±2.09)%vs(40.28±1.47)%.P<0.05],but V20 and V30 of lungs,heart and liver as well as D_(mean)of liver in HT plan were significantly higher than those of VMAT plan(P<0.05),there was no significant difference in whole lungs D_(mean)and heart D_(mean)between 2 plans(P>0.05).The treatment time of VMAT was slightly longer than that of HT plan[(886.67±38.09)seconds vs(843.67±21.61)seconds.P=0.013].Conclusion It is demonstrated that HT and VMAT plan could meet the clinical requirements.The HT dosimetric parameter of PTV is superior to that of VMAT,which showes better protection of s

关 键 词：双侧乳腺癌保乳术 螺旋断层调强放射治疗 容积旋转调强放射治疗 剂量学比较 

分 类 号：R730.55[医药卫生—肿瘤] R737.9[医药卫生—临床医学]