四川医学
四川醫學
사천의학
SICHUAN MEDICAL JOURNAL
2015年
6期
767-773
,共7页
杨瑜%刘丽虹%韩春%王澜%田华
楊瑜%劉麗虹%韓春%王瀾%田華
양유%류려홍%한춘%왕란%전화
容积旋转调强%食管肿瘤%调强放疗%剂量学%肿瘤体积
容積鏇轉調彊%食管腫瘤%調彊放療%劑量學%腫瘤體積
용적선전조강%식관종류%조강방료%제량학%종류체적
volumetric modulated arc therapy%esophageal cancer%intensity modulated radio therapy%dosimetry%tumor volume
目的：比较容积旋转调强( VMAT)与静态调强( IMRT)在不同肿瘤体积及病变长度食管癌中的剂量学差异及优缺点,并评价各自应用的合理性。方法用医科达Oncentra4．1治疗计划系统,为50例胸段食管癌患者分别设计单弧VMAT、静态IMRT计划。根据肿瘤体积及病变长度进行分组,分别比较两种计划的靶区、危及器官受量及总机器跳数(MUs)。结果①GTV体积<15cm3组 VMAT HI更好。15~55cm3组,VMAT PTVD98更接近处方剂量。>55cm3组, VMAT PTVV100低于IMRT。②GTV长度<5cm组,VMAT HI优于IMRT,而CI IMRT更有优势。5~9cm组,VMAT D90低于IMRT,而V95、V90高于IMRT,CI更优。>9cm组,VMAT D90、V100低于IMRT,HI和CI无明显差异。③体积<15cm 3和长度<5cm组,VMAT肺V5、MLD高于IMRT；体积15~55cm 3和长度>9cm组,VMAT肺V10降低,V30增高；体积>55cm 3组,VMAT肺V10低于IMRT；长度5~9cm组,两种计划差异无统计学意义。④GTV体积<55cm 3和长度<9cm组VMAT心脏Dmean高于IMRT,而体积>55cm 3和长度>9cm组两种计划心脏受量相似。脊髓Dmax两种计划比较差异无统计学意义。⑤在机器调数( MU)方面GTV体积15~55cm 3和>55cm 3组及GTV长度5~9cm和>9cm组,VMAT的MU较IMRT分别减少11．3%、18．1%、16．1%和16．0%。而体积<15cm3和长度<5cm组,VMAT的MU则分别增加了10．4%和14．4%。结论在危及器官受量相似的前提下,对于小靶区食管癌VMAT的肿瘤靶区剂量分布优于IMRT,建议首选VMAT。而中等靶区其剂量分布及危及器官受量两种计划相似,但VMAT可明显缩短治疗时间,仍建议首选VMAT。对于大靶区食管癌在剂量学方面VMAT并不占优势,甚至会增加危及器官受量,建议首选IMRT计划。
目的：比較容積鏇轉調彊( VMAT)與靜態調彊( IMRT)在不同腫瘤體積及病變長度食管癌中的劑量學差異及優缺點,併評價各自應用的閤理性。方法用醫科達Oncentra4．1治療計劃繫統,為50例胸段食管癌患者分彆設計單弧VMAT、靜態IMRT計劃。根據腫瘤體積及病變長度進行分組,分彆比較兩種計劃的靶區、危及器官受量及總機器跳數(MUs)。結果①GTV體積<15cm3組 VMAT HI更好。15~55cm3組,VMAT PTVD98更接近處方劑量。>55cm3組, VMAT PTVV100低于IMRT。②GTV長度<5cm組,VMAT HI優于IMRT,而CI IMRT更有優勢。5~9cm組,VMAT D90低于IMRT,而V95、V90高于IMRT,CI更優。>9cm組,VMAT D90、V100低于IMRT,HI和CI無明顯差異。③體積<15cm 3和長度<5cm組,VMAT肺V5、MLD高于IMRT；體積15~55cm 3和長度>9cm組,VMAT肺V10降低,V30增高；體積>55cm 3組,VMAT肺V10低于IMRT；長度5~9cm組,兩種計劃差異無統計學意義。④GTV體積<55cm 3和長度<9cm組VMAT心髒Dmean高于IMRT,而體積>55cm 3和長度>9cm組兩種計劃心髒受量相似。脊髓Dmax兩種計劃比較差異無統計學意義。⑤在機器調數( MU)方麵GTV體積15~55cm 3和>55cm 3組及GTV長度5~9cm和>9cm組,VMAT的MU較IMRT分彆減少11．3%、18．1%、16．1%和16．0%。而體積<15cm3和長度<5cm組,VMAT的MU則分彆增加瞭10．4%和14．4%。結論在危及器官受量相似的前提下,對于小靶區食管癌VMAT的腫瘤靶區劑量分佈優于IMRT,建議首選VMAT。而中等靶區其劑量分佈及危及器官受量兩種計劃相似,但VMAT可明顯縮短治療時間,仍建議首選VMAT。對于大靶區食管癌在劑量學方麵VMAT併不佔優勢,甚至會增加危及器官受量,建議首選IMRT計劃。
목적：비교용적선전조강( VMAT)여정태조강( IMRT)재불동종류체적급병변장도식관암중적제량학차이급우결점,병평개각자응용적합이성。방법용의과체Oncentra4．1치료계화계통,위50례흉단식관암환자분별설계단호VMAT、정태IMRT계화。근거종류체적급병변장도진행분조,분별비교량충계화적파구、위급기관수량급총궤기도수(MUs)。결과①GTV체적<15cm3조 VMAT HI경호。15~55cm3조,VMAT PTVD98경접근처방제량。>55cm3조, VMAT PTVV100저우IMRT。②GTV장도<5cm조,VMAT HI우우IMRT,이CI IMRT경유우세。5~9cm조,VMAT D90저우IMRT,이V95、V90고우IMRT,CI경우。>9cm조,VMAT D90、V100저우IMRT,HI화CI무명현차이。③체적<15cm 3화장도<5cm조,VMAT폐V5、MLD고우IMRT；체적15~55cm 3화장도>9cm조,VMAT폐V10강저,V30증고；체적>55cm 3조,VMAT폐V10저우IMRT；장도5~9cm조,량충계화차이무통계학의의。④GTV체적<55cm 3화장도<9cm조VMAT심장Dmean고우IMRT,이체적>55cm 3화장도>9cm조량충계화심장수량상사。척수Dmax량충계화비교차이무통계학의의。⑤재궤기조수( MU)방면GTV체적15~55cm 3화>55cm 3조급GTV장도5~9cm화>9cm조,VMAT적MU교IMRT분별감소11．3%、18．1%、16．1%화16．0%。이체적<15cm3화장도<5cm조,VMAT적MU칙분별증가료10．4%화14．4%。결론재위급기관수량상사적전제하,대우소파구식관암VMAT적종류파구제량분포우우IMRT,건의수선VMAT。이중등파구기제량분포급위급기관수량량충계화상사,단VMAT가명현축단치료시간,잉건의수선VMAT。대우대파구식관암재제량학방면VMAT병불점우세,심지회증가위급기관수량,건의수선IMRT계화。
Objective To compare the dosimetric differences between volumetric modulated arc therapy ( VMAT ) and static intensity modulated radiotherapy ( IMRT) for different tumor volume and different lesion length of esophageal cancer. Meth-ods The Elekta Oncentra4. 1 Planning System was adopted to design both VMAT and IMRT plans for fifty patients who were diag-nosed with thoracic esophageal cancer. All treatment plans of the 50 cases were evaluated using the dose-volume histogram parame-ters of PTV and the organs at risk. The monitor units (MUs) were Also examined. Results ①For GTV volume<15cm3 group, VMAT plan had superior homogeneity when compared with IMRT plan. For 15~55cm 3 group, PTV D98 for VMAT got closer to prescription dose. However, VMAT plan had lower V100 in the PTV, compared to IMRT plan for GTV volume>55cm 3 group. ②For lesion length<5cm group, VMAT plan led to a superior homogeneity, whereas conformity index was better in IMRT plan. For 5~9cm group, VMAT plan resulted in a slightly lower D90 and higher V95、V90,with superior conformity in the PTV. For lesion length>9cm group,VMAT plan achieved lower D90 and V100, whereas HI and CI were not significantly different.③For GTV vol-ume<15cm 3 group and lesion length<5cm group, lung V5 and MLD were slightly higher for VMAT plan. For 15~55cm 3 group and lesion length>9cm group, VMAT plan resulted in a slightly lower lung V10 and higher lung V30. For GTV volume>55cm 3 group,VMAT plan resulted in a lower lung V10. For 5~9cm group,sparing of lungs showed no statistically significant differences between the two techniques.④The Dmean of heart in VMAT plan was not statistically different in comparison with IMRT plan for GTV volume>55cm 3 group and lesion length>9cm group, but higher than in IMRT for GTV volume<55cm 3 group and lesion length<9cm group. It was no significant difference in VMAT over IMRT for Dmax to the spinal cord.⑤When compared with IM-RT plan, VMAT plan reduced the monitor units by an average of 11. 3% and 18. 1% in the 15 ~55cm 3 group and >55cm 3 group, and by an average of 16. 1% and 16. 0% in the 5~9cm group and >9cm group. However, VMAT plan provided an aver-age of 10. 4% and 14. 4% more monitor units than IMRT plan in the volume<15 cm 3 group and lesion length<5cm group. Con-clusion On the premise of similar sparing of OARs, VMAT plan, which provides superior target volume coverage in comparison with IMRT plan, is the first choice for a small thoracic esophageal target volume. In addition, VMAT plan provides equivalent conformal dose coverage and sparing of OARs for the medium thoracic esophageal target volume with less delivery time. So it is suggested that VMAT is the preferred one. However, IMRT is preferred for a large thoracic esophageal target volume, since VMAT plan has not superior target volume coverage and even increases the spring of OARs.
