体部立体定向放射治疗(Stereotactic Body Radiation Therapy,SBRT)是应用立体定位技术和特殊射线装置,将多源、多线束或多野三维空间聚焦的高能射线聚焦于体内某一靶区,使病灶组织受到高剂量照射,周围正常组织受量减少,从而获得临床疗...体部立体定向放射治疗(Stereotactic Body Radiation Therapy,SBRT)是应用立体定位技术和特殊射线装置,将多源、多线束或多野三维空间聚焦的高能射线聚焦于体内某一靶区,使病灶组织受到高剂量照射,周围正常组织受量减少,从而获得临床疗效高,副作用小的一类放疗技术的总称,采用γ射线所完成的SBRT简称为γ刀,采用X射线所完成的SBRT简称为X刀。SBRT的优势是采用高分次剂量、短疗程分割模式,具有明显的放射生物学优势。无论是国外还是国内,SBRT治疗肿瘤的临床结果均令人鼓舞,治疗早期非小细胞肺癌的3年生存率和局控率均优于常规放疗,与手术效果无差异,而且副作用小,治疗肝癌和胰腺癌的局控率和生存率也获得了大幅度提高。我国的γ刀技术具有独特的剂量聚焦优势和完全自主知识产权,符合我国"十一五"科技自主创新的要求,而且疗效显著、性价比高、易于推广应用符合我国国情。但由于种种原因,SBRT技术在中国尚未引起足够重视,中国γ刀技术需要从设备完善、加大政府支持力度和规范临床应用三个方面进行改进,SBRT的健康发展对推动我国放射肿瘤专业发展具有重要意义。展开更多
目的:比较单纯立体定向放疗或经导管动脉栓塞化疗联合立体定向放疗治疗不可手术结直肠癌肝转移的疗效及安全性。方法:回顾性分析23例不可手术结直肠癌肝转移患者资料,所有患者曾接受一线标准的全身化疗,化疗后肝脏病灶接受或者经导管动...目的:比较单纯立体定向放疗或经导管动脉栓塞化疗联合立体定向放疗治疗不可手术结直肠癌肝转移的疗效及安全性。方法:回顾性分析23例不可手术结直肠癌肝转移患者资料,所有患者曾接受一线标准的全身化疗,化疗后肝脏病灶接受或者经导管动脉栓塞化疗。单纯接受立体定向治疗的13例患者为SBRT组,接受经导管动脉栓塞化疗和立体定向放疗的10例患者为TACE-SBRT组,比较两组患者的肝内病灶局部治疗后的疾病缓解率(RR)、疾病控制率(DCR)和疾病进展时间(TTP),同时观察并发症发生情况,采用Kaplan-Meier、Log-rank检验,Cox回归模型分析中位无进展生存时间(mPFS)和总生存时间(mOS)。结果:SBRT组和TACE-SBRT组的局部治疗反应RR和DCR无统计学意义(P=0.685);与SBRT组相比,TACE-SBRT组的无疾病进展时间延长,差异有统计学意义(11.77±1.56 vs 25.40±5.81,P=0.019)。TACE-SBRT的mPFS优于SBRT组,分别为17.4个月和15.1个月(P<0.05),但是mOS两组之间无统计学意义。同时,仅有1例患者出现Ⅲ级肝功能损伤,治疗后恢复。Cox回归比例风险模型分析确诊肝转移时CEA水平和同时性转移是无进展生存期和总生存期的预后不良因素(P<0.05)。结论:全身化疗后联合SBRT和TACE治疗不可切除的结直肠癌肝转移是一种安全有效的方法,是一种可接受的替代治疗方法,但仍需进一步研究。展开更多
目的:回顾性分析伽马射线体部立体定向放射治疗(stereotactic body radiotherapy,SBRT)治疗肺部原发及转移瘤的急慢性毒副反应和有效性。方法:纳入2013年5月至2015年1月32例肺部原发及转移瘤患者共计47个病灶,中位随访时间9个月,所有患...目的:回顾性分析伽马射线体部立体定向放射治疗(stereotactic body radiotherapy,SBRT)治疗肺部原发及转移瘤的急慢性毒副反应和有效性。方法:纳入2013年5月至2015年1月32例肺部原发及转移瘤患者共计47个病灶,中位随访时间9个月,所有患者均经4DCT定位后采用伽马射线体部立体定向放射治疗。处方剂量及分割模式为63 Gy/9 f(BED10>100 Gy),50%等剂量曲线包绕。RECIST 1.1标准评价疗效,CTC3.0标准评价急慢性毒副反应。结果:所有患者按计划完成处方,随访率100%,完全缓解(CR)89.4%(42个病灶),部分缓解(PR)10.6%(5个病灶),病灶有效反应率(CR+PR)为100%,6个月生存率为93.8%。无3级以上急慢性毒副反应。结论:采用伽马射线体部立体定向放疗治疗肺部原发及转移瘤病灶局部反应率高,急慢性毒副反应可接受。展开更多
The single-isocenter technique in linear accelerator-based stereotactic radiosurgery/stereotactic body radiotherapy (SRS/SBRT) has been broadly used to treat multiple lesions. However, quantitative study to verify tha...The single-isocenter technique in linear accelerator-based stereotactic radiosurgery/stereotactic body radiotherapy (SRS/SBRT) has been broadly used to treat multiple lesions. However, quantitative study to verify that the mechanical field center coincides with the radiation field center when both are off from the isocenter has never been performed. We developed an innovative method to measure this accuracy, called the off-isocenter Winston-Lutz test, and here we provided a practical clinical guideline to implement this technique. We used ImagePro V.6 to analyze images of a Winston-Lutz phantom obtained using a Varian 21EX linear accelerator with an electronic portal imaging device, set up as for single-isocenter SRS/SBRT for multiple lesions. We investigated asymmetry field centers that were 3 cm and 5 cm away from the isocenter, as well as performing the standard Winston-Lutz test. We used a special beam configuration to acquire images while avoiding collision, and we investigated both jaw and multileaf collimation. For the jaw collimator setting, at 3 cm off-isocenter, the mechanical field deviated from the radiation field by about 2.5 mm;at 5 cm, the deviation was above 3 mm, up to 4.27 mm. For the multileaf collimator setting, at 3 cm off- isocenter, the deviation was below 1 mm;at 5 cm, the deviation was above 1 mm, up to 1.72 mm, which was 72% higher than the tolerance threshold. These results indicated that the further the asymmetry field center is from the machine isocenter, the larger the deviation of the mechanical field from the radiation field, and the distance between the center of the asymmetry field and the isocenter should not exceed 3 cm in our clinic. We recommend that every clinic that uses linear accelerator, multileaf collimator-based SRS/SBRT perform the off-isocenter Winston-Lutz test in addition to the standard Winston-Lutz test and use their own deviation data to create planning guideline.展开更多
Purpose: To study the effect of the Qfix kVue Calypso-compatible couch top on the dosimetry of Spine Stereotactic Body Radiation Therapy (SBRT). Methods and Materials: The computed tomography (CT) data set for Qfix kV...Purpose: To study the effect of the Qfix kVue Calypso-compatible couch top on the dosimetry of Spine Stereotactic Body Radiation Therapy (SBRT). Methods and Materials: The computed tomography (CT) data set for Qfix kVue Calypso-compatible couch top with rails were imported into the treatment planning system (TPS). Nine patients who underwent spine SBRT were selected for this study. The inclusion criteria included patients who were treated on a stereotactic linear accelerator with 5 fractions or less from 2016 to 2017 without the couch model. Seven patients were treated with static intensity-modulated radiation therapy (IMRT) fields and two patients were treated using volumetric modulated arc therapy (VMAT) technique. The dose was recalculated for 1) couch top and rails setup (CR) 2) couch-top no rails setup (CNR), and then compared to 3) no couch no-rails setup (NCNR). Dose to 100% of the target volume (D100%), Dose to cover 99% of the target volume (D99%), Dose to cover 95% of the target volume (D95%), Dose to cover 90% of the target volume (D90%), volume receiving 100% of the prescription dose (V100%), conformity index (CI), dose gradient index (DGI), and spinal cord threshold and maximum dose were compared to the plan with NCNR. Results: The average D100% was 77.89% ± 11.78%, 74.51% ± 12.24%, and 75.83 ± 12.67% for NCNR, CR, CNR (р = 0.84), respectively. The average D99% was 91.64% ± 9.57%, 89.93% ± 9.48%, and 91.15% ± 9.55% for NCNR, CR, CNR (р = 0.98), respectively. The average D95% was 99.14% ± 9.96%, 95.23% ± 9.76, and 96.78% ± 9.84% for NCNR, CR, CNR (р = 0.047), respectively. The average D90% was 101.3% ± 0.65%, 97.11% ± 2.48%, and 98.75% ± 2.12% for NCNR, CR, CNR (р = 0.0004), respectively. The maximum dose to the spinal cord was 1750.79 ± 41.84, 1672.90 ± 40.90, and 1709.91 ± 41.35 (cGy) for NCNR, CR, CNR (р = 0.97), respectively. In all cases, the spinal cord threshold dose was far below the tolerances and the differences were insignificant. Average CI was 1.18 ± 0.16, 0.53 ± 0.3展开更多
Purpose: The experimental verification of the Acuros XB (AXB) algorithm was conducted in a heterogeneous rectangular slab phantom, and compared to the Anisotropic Analytical Algorithm (AAA). The dosimetric impact of t...Purpose: The experimental verification of the Acuros XB (AXB) algorithm was conducted in a heterogeneous rectangular slab phantom, and compared to the Anisotropic Analytical Algorithm (AAA). The dosimetric impact of the AXB for stereotactic body radiation therapy (SBRT) and RapidArc planning for 16 non-small-cell lung cancer (NSCLC) patients was assessed due to the dose recalculation from the AAA to the AXB. Methods: The calculated central axis percentage depth doses (PDD) in a heterogeneous slab phantom for an open field size of 3 ×3 cm2 were compared against the PDD measured by an ionization chamber. For 16 NSCLC patients, the dose-volume parameters from the treatment plans calculated by the AXB and the AAA were compared using identical jaw settings, leaf positions, and monitor units (MUs). Results: The results from the heterogeneous slab phantom study showed that the AXB was more accurate than the AAA;however, the dose underestimation by the AXB (up to ?3.9%) and AAA (up to ?13.5%) was observed. For a planning target volume (PTV) in the NSCLC patients, in comparison to the AAA, the AXB predicted lower mean and minimum doses by average 0.3% and 4.3% respectively, but a higher maximum dose by average 2.3%. The averaged maximum doses to the heart and spinal cord predicted by the AXB were lower by 1.3% and 2.6% respectively;whereas the doses to the lungs predicted by the AXB were higher by up to 0.5% compared to the AAA. The percentage of ipsilateral lung volume receiving at least 20 and 5 Gy (V20 and V5 respectively) were higher in the AXB plans than in the AAA plans by average 1.1% and 2.8% respectively. The AXB plans produced higher target heterogeneity by average 4.5% and lower plan conformity by average 5.8% compared to the AAA plans. Using the AXB, the PTV coverage (95% of the PTV covered by the 100% of the prescribed dose) was reduced by average 8.2% than using the AAA. The AXB plans required about 2.3% increment in the number of MUs in order to achieve the same PTV coverage as in the AAA plans. Conclusion展开更多
随着恶性肿瘤综合治疗的发展,发生脊柱转移的患者预期寿命延长,提高脊柱转移瘤的局部控制率成为临床关注的热点。立体定向放射治疗(stereotactic body radiotherapy,SBRT)是利用高度适形的放疗计划和图像引导技术,将根治性的放射剂量通...随着恶性肿瘤综合治疗的发展,发生脊柱转移的患者预期寿命延长,提高脊柱转移瘤的局部控制率成为临床关注的热点。立体定向放射治疗(stereotactic body radiotherapy,SBRT)是利用高度适形的放疗计划和图像引导技术,将根治性的放射剂量通过外照射的方式聚焦到肿瘤部位,达到消灭肿瘤的目的。目前越来越多SBRT技术用于脊柱转移瘤的治疗。为更好地治疗脊柱转移瘤,NOMS(neurologic,oncologic,mechanical,and systemic)决策框架的概念被引入临床实践中,它将立体定向放射治疗、分离手术、脊柱的稳定和常规分割放疗联合起来,为脊柱转移瘤提供最佳治疗策略。脊柱转移瘤SBRT,局控率高,副作用小,但是需要注意危及器官剂量的限制。该文对NOMS中关于脊柱转移瘤SBRT的一些建议进行解读,为临床肿瘤放射医师提供参考。展开更多
文摘体部立体定向放射治疗(Stereotactic Body Radiation Therapy,SBRT)是应用立体定位技术和特殊射线装置,将多源、多线束或多野三维空间聚焦的高能射线聚焦于体内某一靶区,使病灶组织受到高剂量照射,周围正常组织受量减少,从而获得临床疗效高,副作用小的一类放疗技术的总称,采用γ射线所完成的SBRT简称为γ刀,采用X射线所完成的SBRT简称为X刀。SBRT的优势是采用高分次剂量、短疗程分割模式,具有明显的放射生物学优势。无论是国外还是国内,SBRT治疗肿瘤的临床结果均令人鼓舞,治疗早期非小细胞肺癌的3年生存率和局控率均优于常规放疗,与手术效果无差异,而且副作用小,治疗肝癌和胰腺癌的局控率和生存率也获得了大幅度提高。我国的γ刀技术具有独特的剂量聚焦优势和完全自主知识产权,符合我国"十一五"科技自主创新的要求,而且疗效显著、性价比高、易于推广应用符合我国国情。但由于种种原因,SBRT技术在中国尚未引起足够重视,中国γ刀技术需要从设备完善、加大政府支持力度和规范临床应用三个方面进行改进,SBRT的健康发展对推动我国放射肿瘤专业发展具有重要意义。
文摘目的:比较单纯立体定向放疗或经导管动脉栓塞化疗联合立体定向放疗治疗不可手术结直肠癌肝转移的疗效及安全性。方法:回顾性分析23例不可手术结直肠癌肝转移患者资料,所有患者曾接受一线标准的全身化疗,化疗后肝脏病灶接受或者经导管动脉栓塞化疗。单纯接受立体定向治疗的13例患者为SBRT组,接受经导管动脉栓塞化疗和立体定向放疗的10例患者为TACE-SBRT组,比较两组患者的肝内病灶局部治疗后的疾病缓解率(RR)、疾病控制率(DCR)和疾病进展时间(TTP),同时观察并发症发生情况,采用Kaplan-Meier、Log-rank检验,Cox回归模型分析中位无进展生存时间(mPFS)和总生存时间(mOS)。结果:SBRT组和TACE-SBRT组的局部治疗反应RR和DCR无统计学意义(P=0.685);与SBRT组相比,TACE-SBRT组的无疾病进展时间延长,差异有统计学意义(11.77±1.56 vs 25.40±5.81,P=0.019)。TACE-SBRT的mPFS优于SBRT组,分别为17.4个月和15.1个月(P<0.05),但是mOS两组之间无统计学意义。同时,仅有1例患者出现Ⅲ级肝功能损伤,治疗后恢复。Cox回归比例风险模型分析确诊肝转移时CEA水平和同时性转移是无进展生存期和总生存期的预后不良因素(P<0.05)。结论:全身化疗后联合SBRT和TACE治疗不可切除的结直肠癌肝转移是一种安全有效的方法,是一种可接受的替代治疗方法,但仍需进一步研究。
文摘The single-isocenter technique in linear accelerator-based stereotactic radiosurgery/stereotactic body radiotherapy (SRS/SBRT) has been broadly used to treat multiple lesions. However, quantitative study to verify that the mechanical field center coincides with the radiation field center when both are off from the isocenter has never been performed. We developed an innovative method to measure this accuracy, called the off-isocenter Winston-Lutz test, and here we provided a practical clinical guideline to implement this technique. We used ImagePro V.6 to analyze images of a Winston-Lutz phantom obtained using a Varian 21EX linear accelerator with an electronic portal imaging device, set up as for single-isocenter SRS/SBRT for multiple lesions. We investigated asymmetry field centers that were 3 cm and 5 cm away from the isocenter, as well as performing the standard Winston-Lutz test. We used a special beam configuration to acquire images while avoiding collision, and we investigated both jaw and multileaf collimation. For the jaw collimator setting, at 3 cm off-isocenter, the mechanical field deviated from the radiation field by about 2.5 mm;at 5 cm, the deviation was above 3 mm, up to 4.27 mm. For the multileaf collimator setting, at 3 cm off- isocenter, the deviation was below 1 mm;at 5 cm, the deviation was above 1 mm, up to 1.72 mm, which was 72% higher than the tolerance threshold. These results indicated that the further the asymmetry field center is from the machine isocenter, the larger the deviation of the mechanical field from the radiation field, and the distance between the center of the asymmetry field and the isocenter should not exceed 3 cm in our clinic. We recommend that every clinic that uses linear accelerator, multileaf collimator-based SRS/SBRT perform the off-isocenter Winston-Lutz test in addition to the standard Winston-Lutz test and use their own deviation data to create planning guideline.
文摘Purpose: To study the effect of the Qfix kVue Calypso-compatible couch top on the dosimetry of Spine Stereotactic Body Radiation Therapy (SBRT). Methods and Materials: The computed tomography (CT) data set for Qfix kVue Calypso-compatible couch top with rails were imported into the treatment planning system (TPS). Nine patients who underwent spine SBRT were selected for this study. The inclusion criteria included patients who were treated on a stereotactic linear accelerator with 5 fractions or less from 2016 to 2017 without the couch model. Seven patients were treated with static intensity-modulated radiation therapy (IMRT) fields and two patients were treated using volumetric modulated arc therapy (VMAT) technique. The dose was recalculated for 1) couch top and rails setup (CR) 2) couch-top no rails setup (CNR), and then compared to 3) no couch no-rails setup (NCNR). Dose to 100% of the target volume (D100%), Dose to cover 99% of the target volume (D99%), Dose to cover 95% of the target volume (D95%), Dose to cover 90% of the target volume (D90%), volume receiving 100% of the prescription dose (V100%), conformity index (CI), dose gradient index (DGI), and spinal cord threshold and maximum dose were compared to the plan with NCNR. Results: The average D100% was 77.89% ± 11.78%, 74.51% ± 12.24%, and 75.83 ± 12.67% for NCNR, CR, CNR (р = 0.84), respectively. The average D99% was 91.64% ± 9.57%, 89.93% ± 9.48%, and 91.15% ± 9.55% for NCNR, CR, CNR (р = 0.98), respectively. The average D95% was 99.14% ± 9.96%, 95.23% ± 9.76, and 96.78% ± 9.84% for NCNR, CR, CNR (р = 0.047), respectively. The average D90% was 101.3% ± 0.65%, 97.11% ± 2.48%, and 98.75% ± 2.12% for NCNR, CR, CNR (р = 0.0004), respectively. The maximum dose to the spinal cord was 1750.79 ± 41.84, 1672.90 ± 40.90, and 1709.91 ± 41.35 (cGy) for NCNR, CR, CNR (р = 0.97), respectively. In all cases, the spinal cord threshold dose was far below the tolerances and the differences were insignificant. Average CI was 1.18 ± 0.16, 0.53 ± 0.3
文摘Purpose: The experimental verification of the Acuros XB (AXB) algorithm was conducted in a heterogeneous rectangular slab phantom, and compared to the Anisotropic Analytical Algorithm (AAA). The dosimetric impact of the AXB for stereotactic body radiation therapy (SBRT) and RapidArc planning for 16 non-small-cell lung cancer (NSCLC) patients was assessed due to the dose recalculation from the AAA to the AXB. Methods: The calculated central axis percentage depth doses (PDD) in a heterogeneous slab phantom for an open field size of 3 ×3 cm2 were compared against the PDD measured by an ionization chamber. For 16 NSCLC patients, the dose-volume parameters from the treatment plans calculated by the AXB and the AAA were compared using identical jaw settings, leaf positions, and monitor units (MUs). Results: The results from the heterogeneous slab phantom study showed that the AXB was more accurate than the AAA;however, the dose underestimation by the AXB (up to ?3.9%) and AAA (up to ?13.5%) was observed. For a planning target volume (PTV) in the NSCLC patients, in comparison to the AAA, the AXB predicted lower mean and minimum doses by average 0.3% and 4.3% respectively, but a higher maximum dose by average 2.3%. The averaged maximum doses to the heart and spinal cord predicted by the AXB were lower by 1.3% and 2.6% respectively;whereas the doses to the lungs predicted by the AXB were higher by up to 0.5% compared to the AAA. The percentage of ipsilateral lung volume receiving at least 20 and 5 Gy (V20 and V5 respectively) were higher in the AXB plans than in the AAA plans by average 1.1% and 2.8% respectively. The AXB plans produced higher target heterogeneity by average 4.5% and lower plan conformity by average 5.8% compared to the AAA plans. Using the AXB, the PTV coverage (95% of the PTV covered by the 100% of the prescribed dose) was reduced by average 8.2% than using the AAA. The AXB plans required about 2.3% increment in the number of MUs in order to achieve the same PTV coverage as in the AAA plans. Conclusion
文摘随着恶性肿瘤综合治疗的发展,发生脊柱转移的患者预期寿命延长,提高脊柱转移瘤的局部控制率成为临床关注的热点。立体定向放射治疗(stereotactic body radiotherapy,SBRT)是利用高度适形的放疗计划和图像引导技术,将根治性的放射剂量通过外照射的方式聚焦到肿瘤部位,达到消灭肿瘤的目的。目前越来越多SBRT技术用于脊柱转移瘤的治疗。为更好地治疗脊柱转移瘤,NOMS(neurologic,oncologic,mechanical,and systemic)决策框架的概念被引入临床实践中,它将立体定向放射治疗、分离手术、脊柱的稳定和常规分割放疗联合起来,为脊柱转移瘤提供最佳治疗策略。脊柱转移瘤SBRT,局控率高,副作用小,但是需要注意危及器官剂量的限制。该文对NOMS中关于脊柱转移瘤SBRT的一些建议进行解读,为临床肿瘤放射医师提供参考。
