目的探究在Halcyon直线加速器上使用调强适形放射治疗(IMRT)和容积旋转调强放射治疗(VMAT)进行乳腺癌保乳术后放射治疗的临床应用。方法选择乳腺癌保乳术后放射治疗患者25例,年龄36~61岁,平均年龄50.9岁;左侧乳腺癌15例,右侧乳腺癌10例...目的探究在Halcyon直线加速器上使用调强适形放射治疗(IMRT)和容积旋转调强放射治疗(VMAT)进行乳腺癌保乳术后放射治疗的临床应用。方法选择乳腺癌保乳术后放射治疗患者25例,年龄36~61岁,平均年龄50.9岁;左侧乳腺癌15例,右侧乳腺癌10例;肿瘤分期均为T1~T2、N0、M0。计划设计均在Eclipse计划系统上,每例患者分别采用IMRT和VMAT进行计划设计。对两类计划的主要剂量学参数、剂量分布、γ通过率和照射时间进行比较。结果所有计划均可临床使用,两组计划靶区D_(95%)、平均剂量D_(mean)差异较小(P>0.05),靶区均匀性指数(HI)(IMRT组0.06±0.01 vs VMAT组0.06±0.01),差异无统计学意义(P>0.05),适形性指数(CI)(IMRT组0.85±0.03 vs VMAT组0.92±0.02),差异有统计学意义(P<0.05)。IMRT组患侧肺V_(5)、V_(20)和平均剂量,心脏平均剂量,健侧肺V_(5)均低于VMAT组,差异具有统计学意义[患侧肺V_(5)(41.36±2.04)%vs(47.58±2.42)%、患侧肺V_(20)(15.04±2.90)%vs(16.35±1.97)%、患侧肺平均剂量(886.32±79.41)cGy vs(993.49±50.14)cGy、心脏平均剂量(209.23±98.12)cGy vs(277.60±83.18)cGy、健侧肺V_(5)(2.10±1.35)%vs(14.06±8.62)%。P<0.05]。VMAT组γ通过率优于IMRT组,差异有统计学意义[3 mm/3%(99.72±0.20)%vs(99.38±0.37)%;2 mm/2%(97.22±1.05)%vs(96.99±0.91)%。P<0.05]。IMRT组照射时间(2.08±0.27)min,VMAT组照射时间(0.87±0.04)min,VMAT组节省超过55%照射时间,差异有统计学意义(P<0.05)。结论使用Halcyon直线加速器进行保乳术后放射治疗,IMRT计划和VMAT计划均能满足临床治疗需求,采用VMAT技术会提高靶区的剂量分布,明显提高计划执行效率。展开更多
目的基于Halcyon加速器比较左乳腺癌改良根治术后2弧、3弧、4弧和5弧的容积调强放射治疗(VMAT)计划的剂量学差异。方法选择德阳市人民医院肿瘤科行左侧乳腺癌改良根治术后患者20例,均为女性;年龄32~69岁,中位年龄51岁;肿瘤分期均为T3~T4...目的基于Halcyon加速器比较左乳腺癌改良根治术后2弧、3弧、4弧和5弧的容积调强放射治疗(VMAT)计划的剂量学差异。方法选择德阳市人民医院肿瘤科行左侧乳腺癌改良根治术后患者20例,均为女性;年龄32~69岁,中位年龄51岁;肿瘤分期均为T3~T4、N1;位置为非内象限。基于Halcyon加速器为每位患者分别设计2弧、3弧、4弧和5弧4组VMAT计划。比较4组计划的计划靶区体积(PTV)和危及器官的剂量学指标、跳数(MU)、出束时间和γ通过率的差异。结果4弧组和5弧组VMAT计划在PTV的适形度指数(CI)、均匀性指数(HI)、D_(98)、D_(50)、D_(2)和Dmean上均优于2弧组和3弧组,而5弧组仅在PTV的D_(2)稍低于4弧组[(5311.9±30.74)cGy vs(5332.5±31.13)cGy。P<0.05]。危及器官,4弧组和5弧组左肺(患侧肺)V_(5)、V_(20)、V_(30)、V_(40)和Dmean最低,V_(10)亦低于3弧组[(33.09±2.60)%vs(32.98±2.65)%vs(34.23±2.53)%。P<0.05]。4弧组和5弧组右肺(健侧肺)Dmean低于2弧组[435(339,464)cGy vs 435(394,462)cGy vs 447(417,490)cGy。P<0.05]。4弧组和5弧组心脏V_(20)[(7.96±4.17)%、(7.99±4.19)%]和V_(30)[(3.60±2.58)%、(3.41±2.46)%]最低,V_(10)和Dmean亦低于2弧组[22.8(17.7,25.7)%vs 22.6(18.3,25.7)%vs 23.75(19.0,27.5)%、836(705,898)cGy vs 835(708,931)cGy vs 857(741,959)cGy。P<0.05]。4弧组和5弧组食管Dmean[(1362.0±370.4)cGy、(1363.2±367.3)cGy]最低,右乳Dmax亦低于2弧组[(901.4±162.9)cGy vs(900.4±170.4)cGy vs(973.9±181.5)cGy。P<0.05]。5弧组与4弧组各危及器官的剂量差异均无统计学意义(P>0.05)。4弧组MU和出束时间较2弧组和3弧组有少量增加,分别增加26.15 MU、0.05 min和28.9 MU、0.04 min,5弧组较4弧组也分别增加31.8 MU和0.05 min(P<0.05)。4组计划的γ通过率均>95%,组间差异无统计学意义(P>0.05)。结论4弧的乳腺癌VMAT计划可获得更优的剂量学分布。因此推荐左乳腺癌改良根治术后在Halcyon加速器上采用4弧的VMAT计划。展开更多
BACKGROUND Radiation therapy,especially the development of linear accelerators,plays a key role in cancer management.The fast-rotating coplanar O-ring Halcyon Linac has demonstrated many advantages.The previous litera...BACKGROUND Radiation therapy,especially the development of linear accelerators,plays a key role in cancer management.The fast-rotating coplanar O-ring Halcyon Linac has demonstrated many advantages.The previous literature has mainly focused on the machine parameters and plan quality of Halcyon,with a lack of relevant research on its clinical application.AIM To evaluate the clinical performance of the O-ring Halcyon treatment system in a real-world application setting.METHODS Data from sixty-one patients who were treated with the Halcyon system throughout the entire radiotherapy process in Peking Union Medical College Hospital between August 2019 and September 2020 were retrospectively reviewed.We evaluated the target tumour response to radiotherapy and irradiation toxicity from 1 to 3 mo after treatment.Dosimetric verification of Halcyon plans was performed using a quality assurance procedure,including portal dosimetry,ArcCHECK and point dose measurements for verification of the system delivery accuracy.RESULTS Of the 61 patients in the five groups,16,12,7 and 26 patients had complete response,partial response,progressive disease and stable disease,respectively.No increase in the irradiated target tumour volume was observed when separately evaluating the local response.Regarding irradiation toxicity,no radiation-induced deaths were observed.Thirty-eight percent(23/61 patients)had no radiation toxicity after radiotherapy,56%(34/61 patients)experienced radiation toxicity that resolved after treatment,and 6%(4/61 patients)had irreversible adverse reactions.The average gamma passing rates with a 2%dose difference and 2-mm distance to agreement for IMRT/VMAT/SRT plans were ArcCHECK at 96.4%and portal dosimetry at 96.7%,respectively.All of the validated clinical plans were within 3%for point dose measurements,and Halcyon’s ArcCHECK demonstrated a high pass rate of 99.1%±1.1%for clinical gamma passing criteria of 3%/3 mm.CONCLUSION The O-ring Halcyon Linac could achieve a better therapeutic effect on the target volume by providing accurate treatment delivery plans with tolerable irradiation toxicity.展开更多
文摘目的探究在Halcyon直线加速器上使用调强适形放射治疗(IMRT)和容积旋转调强放射治疗(VMAT)进行乳腺癌保乳术后放射治疗的临床应用。方法选择乳腺癌保乳术后放射治疗患者25例,年龄36~61岁,平均年龄50.9岁;左侧乳腺癌15例,右侧乳腺癌10例;肿瘤分期均为T1~T2、N0、M0。计划设计均在Eclipse计划系统上,每例患者分别采用IMRT和VMAT进行计划设计。对两类计划的主要剂量学参数、剂量分布、γ通过率和照射时间进行比较。结果所有计划均可临床使用,两组计划靶区D_(95%)、平均剂量D_(mean)差异较小(P>0.05),靶区均匀性指数(HI)(IMRT组0.06±0.01 vs VMAT组0.06±0.01),差异无统计学意义(P>0.05),适形性指数(CI)(IMRT组0.85±0.03 vs VMAT组0.92±0.02),差异有统计学意义(P<0.05)。IMRT组患侧肺V_(5)、V_(20)和平均剂量,心脏平均剂量,健侧肺V_(5)均低于VMAT组,差异具有统计学意义[患侧肺V_(5)(41.36±2.04)%vs(47.58±2.42)%、患侧肺V_(20)(15.04±2.90)%vs(16.35±1.97)%、患侧肺平均剂量(886.32±79.41)cGy vs(993.49±50.14)cGy、心脏平均剂量(209.23±98.12)cGy vs(277.60±83.18)cGy、健侧肺V_(5)(2.10±1.35)%vs(14.06±8.62)%。P<0.05]。VMAT组γ通过率优于IMRT组,差异有统计学意义[3 mm/3%(99.72±0.20)%vs(99.38±0.37)%;2 mm/2%(97.22±1.05)%vs(96.99±0.91)%。P<0.05]。IMRT组照射时间(2.08±0.27)min,VMAT组照射时间(0.87±0.04)min,VMAT组节省超过55%照射时间,差异有统计学意义(P<0.05)。结论使用Halcyon直线加速器进行保乳术后放射治疗,IMRT计划和VMAT计划均能满足临床治疗需求,采用VMAT技术会提高靶区的剂量分布,明显提高计划执行效率。
文摘目的基于Halcyon加速器比较左乳腺癌改良根治术后2弧、3弧、4弧和5弧的容积调强放射治疗(VMAT)计划的剂量学差异。方法选择德阳市人民医院肿瘤科行左侧乳腺癌改良根治术后患者20例,均为女性;年龄32~69岁,中位年龄51岁;肿瘤分期均为T3~T4、N1;位置为非内象限。基于Halcyon加速器为每位患者分别设计2弧、3弧、4弧和5弧4组VMAT计划。比较4组计划的计划靶区体积(PTV)和危及器官的剂量学指标、跳数(MU)、出束时间和γ通过率的差异。结果4弧组和5弧组VMAT计划在PTV的适形度指数(CI)、均匀性指数(HI)、D_(98)、D_(50)、D_(2)和Dmean上均优于2弧组和3弧组,而5弧组仅在PTV的D_(2)稍低于4弧组[(5311.9±30.74)cGy vs(5332.5±31.13)cGy。P<0.05]。危及器官,4弧组和5弧组左肺(患侧肺)V_(5)、V_(20)、V_(30)、V_(40)和Dmean最低,V_(10)亦低于3弧组[(33.09±2.60)%vs(32.98±2.65)%vs(34.23±2.53)%。P<0.05]。4弧组和5弧组右肺(健侧肺)Dmean低于2弧组[435(339,464)cGy vs 435(394,462)cGy vs 447(417,490)cGy。P<0.05]。4弧组和5弧组心脏V_(20)[(7.96±4.17)%、(7.99±4.19)%]和V_(30)[(3.60±2.58)%、(3.41±2.46)%]最低,V_(10)和Dmean亦低于2弧组[22.8(17.7,25.7)%vs 22.6(18.3,25.7)%vs 23.75(19.0,27.5)%、836(705,898)cGy vs 835(708,931)cGy vs 857(741,959)cGy。P<0.05]。4弧组和5弧组食管Dmean[(1362.0±370.4)cGy、(1363.2±367.3)cGy]最低,右乳Dmax亦低于2弧组[(901.4±162.9)cGy vs(900.4±170.4)cGy vs(973.9±181.5)cGy。P<0.05]。5弧组与4弧组各危及器官的剂量差异均无统计学意义(P>0.05)。4弧组MU和出束时间较2弧组和3弧组有少量增加,分别增加26.15 MU、0.05 min和28.9 MU、0.04 min,5弧组较4弧组也分别增加31.8 MU和0.05 min(P<0.05)。4组计划的γ通过率均>95%,组间差异无统计学意义(P>0.05)。结论4弧的乳腺癌VMAT计划可获得更优的剂量学分布。因此推荐左乳腺癌改良根治术后在Halcyon加速器上采用4弧的VMAT计划。
基金Supported by the National Foundation for Education Sciences Planning,No. BLA 200216the National Key Research and Development Plan,Ministry of Science and Technology of the People’s Republic of China,No. 2016YFC0105207
文摘BACKGROUND Radiation therapy,especially the development of linear accelerators,plays a key role in cancer management.The fast-rotating coplanar O-ring Halcyon Linac has demonstrated many advantages.The previous literature has mainly focused on the machine parameters and plan quality of Halcyon,with a lack of relevant research on its clinical application.AIM To evaluate the clinical performance of the O-ring Halcyon treatment system in a real-world application setting.METHODS Data from sixty-one patients who were treated with the Halcyon system throughout the entire radiotherapy process in Peking Union Medical College Hospital between August 2019 and September 2020 were retrospectively reviewed.We evaluated the target tumour response to radiotherapy and irradiation toxicity from 1 to 3 mo after treatment.Dosimetric verification of Halcyon plans was performed using a quality assurance procedure,including portal dosimetry,ArcCHECK and point dose measurements for verification of the system delivery accuracy.RESULTS Of the 61 patients in the five groups,16,12,7 and 26 patients had complete response,partial response,progressive disease and stable disease,respectively.No increase in the irradiated target tumour volume was observed when separately evaluating the local response.Regarding irradiation toxicity,no radiation-induced deaths were observed.Thirty-eight percent(23/61 patients)had no radiation toxicity after radiotherapy,56%(34/61 patients)experienced radiation toxicity that resolved after treatment,and 6%(4/61 patients)had irreversible adverse reactions.The average gamma passing rates with a 2%dose difference and 2-mm distance to agreement for IMRT/VMAT/SRT plans were ArcCHECK at 96.4%and portal dosimetry at 96.7%,respectively.All of the validated clinical plans were within 3%for point dose measurements,and Halcyon’s ArcCHECK demonstrated a high pass rate of 99.1%±1.1%for clinical gamma passing criteria of 3%/3 mm.CONCLUSION The O-ring Halcyon Linac could achieve a better therapeutic effect on the target volume by providing accurate treatment delivery plans with tolerable irradiation toxicity.
