Background Few studies were reported on the comparison of clinical outcomes between intensity-modulated radiotherapy （IMRT） and three-dimensional conformal radiotherapy （3D-CRT） in the treatment of glioblastoma mu...Background Few studies were reported on the comparison of clinical outcomes between intensity-modulated radiotherapy （IMRT） and three-dimensional conformal radiotherapy （3D-CRT） in the treatment of glioblastoma multiforme （GBM）.This study aimed to determine whether IMRT improves clinical outcomes compared with 3D-CRT in patients with GBM.Methods The records of 54 patients with newly-diagnosed GBM from July 2009 to December 2010 were reviewed.The patients underwent postoperative IMRT or 3D-CRT with concurrent and adjuvant temozolomide.Kaplan-Meier method and log rank test were used to estimate differences of patients＇ survival.Results The median follow-up was 13 months.Of the 54 patients,fifty （92.6%） completed the combined modality treatment.The 1-year overall survival rate （OS） was 79.6%.The pattern of failure was predominantly local.A comparative analysis revealed that no statistical difference was observed between the IMRT group （n=21） and the 3D-CRT group （n=33） for 1-year OS （89.6% vs.75.8%,P=0.795）,or 1-year progression-free survival （PFS） （61.0% vs.45.5%,P=0.867）.In dosimetric comparison,IMRT seemed to allow better sparing of organs at risk than 3D-CRT did （P=0.050,P=0.055）.However,there was no significant difference for toxicities of irradiation between the IMRT group and the 3D-CRT group.Conclusions Our preliminary results suggested that delivering standard radiation doses by IMRT is unlikely to improve local control or overall survival for GBM compared with 3D-CRT.Given this lack of survival benefit and increased costs of IMRT,the utilization of IMRT treatment for GBM needs to be carefully rationalized.展开更多
AIM To analyse clinical and dosimetric results of helical tomotherapy(HT) and volumetric modulated arc therapy(VMAT) in complex adjuvant breast and nodes irradiation.METHODS Seventy-three patients were included(31 HT ...AIM To analyse clinical and dosimetric results of helical tomotherapy(HT) and volumetric modulated arc therapy(VMAT) in complex adjuvant breast and nodes irradiation.METHODS Seventy-three patients were included(31 HT and 42 VMAT). Dose were 63.8 Gy(HT) and 63.2 Gy(VMAT) in the tumour bed, 52.2 Gy in the breast, 50.4 Gy in supraclavicular nodes(SCN) and internal mammary chain(IMC) with HT and 52.2 Gy and 49.3 Gy in IMC and SCN with VMAT in 29 fractions. Margins to particle tracking velocimetry were greater in the VMAT cohort(7 mm vs 5 mm).RESULTS For the HT cohort, the coverage of clinical target volumes was as follows: Tumour bed: 99.4% ± 2.4%; breast: 98.4% ± 4.3%; SCN: 99.5% ± 1.2%; IMC:96.5% ± 13.9%. For the VMAT cohort, the coverage was as follows: Tumour bed: 99.7% ± 0.5%, breast: 99.3% ± 0.7%; SCN: 99.6% ± 1.4%; IMC: 99.3% ± 3%. For ipsilateral lung, Dmean and V20 were 13.6 ± 1.2 Gy, 21.1% ± 5%(HT) and 13.6 ± 1.4 Gy, 20.1% ± 3.2%(VMAT). Dmean and V30 of the heart were 7.4 ± 1.4 Gy, 1% ± 1%(HT) and 10.3 ± 4.2 Gy, 2.5% ± 3.9%(VMAT). For controlateral breast Dmean was 3.6 ± 0.2 Gy(HT) and 4.6 ± 0.9 Gy(VMAT). Acute skin toxicity grade 3 was 5% in the two cohorts.CONCLUSION HT and VMAT in complex adjuvant breast irradiation allow a good coverage of target volumes with an acceptable acute tolerance. A longer follow-up is needed to assess the impact of low doses to healthy tissues.展开更多
AIM:To assess the feasibility of volumetric intensity-modulated arc radiotherapy (VMAT) in patients with limited polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes syndrome. METHODS:...AIM:To assess the feasibility of volumetric intensity-modulated arc radiotherapy (VMAT) in patients with limited polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes syndrome. METHODS:A 70-year-old male with histologically confirmed osteosclerotic myeloma was treated in our department in July 2010 with VMAT. Fourty-six Gray in 23 fractions were given on three bone lesions. Doses delivered to target volume and critical organs were compared with a tridimensional conformal radiotherapy (3D-RT) plan. Treatment was well tolerated without any side effects.RESULTS:VMAT improved dose homogeneity within the target volume, as compared to 3D-RT (standard deviations:2.9 Gy and 1.6 Gy for 3D and VMAT, respectively). VMAT resulted in a better sparing of critical organs. Dose delivered to 20% of organ volume (D20) was reduced from 22 Gy (3D-RT) to 15 Gy (VMAT) for small bowel, from 24 Gy (3D-RT) to 17 Gy (VMAT) for bladder and from 47 Gy (3D-RT) to 3 Gy (VMAT) for spinal cord. Volumes of critical organs that received at least 20 Gy (V20) were decreased by the use of VMAT, as compared to 3D-RT (V20 bladder:10% vs 99%; V20 small bowel:6% vs 21%). One year after treatment completion, no tumor progression has been reported. CONCLUSION:VMAT improved dose distribution as compared to 3D-RT for limited osteosclerotic myeloma, with better saving of critical organs.展开更多
AIM:To establish the feasibility of simultaneous modulated accelerated radiation therapy(SMART) in esophageal cancer(EC).METHODS:Computed tomography(CT)datasets of 10patients with upper or middle thoracic squamous cel...AIM:To establish the feasibility of simultaneous modulated accelerated radiation therapy(SMART) in esophageal cancer(EC).METHODS:Computed tomography(CT)datasets of 10patients with upper or middle thoracic squamous cell EC undergoing chemoradiotherapy were used to generate SMART,conventionally-fractionated three-dimensional conformal radiotherapy(3DCRT)and intensity-modulated radiation therapy(cf-IMRT)plans,respectively.The gross target volume(GTV)of the esophagus,positive regional lymph nodes(LN),and suspected lymph nodes(LN±)were contoured for each patient.The clinical target volume(CTV)was delineated with 2-cm longitudinal and 0.5-to 1.0-cm radial margins with respect to the GTV and with 0.5-cm uniform margins for LN and LN(±).For the SMART plans,there were two planning target volumes(PTVs):PTV66=(GTV+LN)+0.5 cm and PTV54=CTV+0.5 cm.For the 3DCRT and cfIMRT plans,there was only a single PTV:PTV60=CTV+0.5 cm.The prescribed dose for the SMART plans was 66 Gy/30 F to PTV66 and 54 Gy/30 F to PTV54.The dose prescription to the PTV60 for both the 3DCRT and cf-IMRT plans was set to 60 Gy/30 F.All the plans were generated on the Eclipse 10.0 treatment planning system.Fulfillment of the dose criteria for the PTVs received the highest priority,followed by the spinal cord,heart,and lungs.The dose-volume histograms were compared.RESULTS:Clinically acceptable plans were achieved for all the SMART,cf-IMRT,and 3DCRT plans.Compared with the 3DCRT plans,the SMART plans increased the dose delivered to the primary tumor(66Gy vs 60 Gy),with improved sparing of normal tissues in all patients.The Dmax of the spinal cord,V20 of the lungs,and Dmean and V50 of the heart for the SMART and 3DCRT plans were as follows:38.5±2.0 vs 44.7±0.8(P=0.002),17.1±4.0 vs 25.8±5.0(P=0.000),14.4±7.5 vs 21.4±11.1(P=0.000),and 4.9±3.4vs 12.9±7.6(P=0.000),respectively.In contrast to the cf-IMRT plans,the SMART plans permitted a simultaneous dose escalation(6 Gy)to the primary tumor while demonstrating a significant trend of a lower irradiation dose to all organs at risk except the spinal cord,for which no significant difference was found.CONCLUSION:SMART offers the potential for a 6Gy simultaneous escalation in the irradiation dose delivered to the primary tumor of EC and improves the sparing of normal tissues.展开更多
Radiotherapy techniques have substantially improved in the last two decades. After the introduction of 3-dimensional conformal radiotherapy, radiotherapy has been increasingly used for the treatment of hepatocellular ...Radiotherapy techniques have substantially improved in the last two decades. After the introduction of 3-dimensional conformal radiotherapy, radiotherapy has been increasingly used for the treatment of hepatocellular carcinoma(HCC). Currently, more advanced techniques, including intensity-modulated radiotherapy(IMRT), stereotactic ablative body radiotherapy(SABR), and charged particle therapy, are used for the treatment of HCC. IMRT can escalate the tumor dose while sparing the normal tissue even though the tumor is large or located near critical organs. SABR can deliver a very high radiation dose to small HCCs in a few fractions, leading to high local control rates of 84%-100%. Various advanced imaging modalities are used for radiotherapy planning and delivery to improve the precision of radiotherapy. These advanced techniques enable the delivery of high dose radiotherapy for early to advanced HCCs without increasing the radiation-induced toxicities. However, as there have been no effective tools for the prediction of the response to radiotherapy or recurrences within or outside the radiation field, future studies should focus on selecting the patients who will benefit from radiotherapy.展开更多
Introduction: In medulloblastoma patients craniospinal irradiation is an important element the treatment. Our study aimed to evaluate the effect of absorbed dose to organs at risk using the hybrid intensity-modulated ...Introduction: In medulloblastoma patients craniospinal irradiation is an important element the treatment. Our study aimed to evaluate the effect of absorbed dose to organs at risk using the hybrid intensity-modulated radiation therapy (IMRT) versus three-dimensional conformal radiotherapy (3DCRT) for craniospinal irradiation (CSI) in average risk medulloblastoma patients. Materials and Methods: In this study, thirteen medulloblastoma patients were included. The prescribed total dose to the planning target volume (PTV) was 23, 40 Gy in 13 fractions. Two radiotherapy techniques, three dimensional conformal radiotherapy (3DCRT) and hybrid intensity modulated radiotherapy (IMRT) were used to treat these patients. The coverage of the Target was evaluated using the D mean, D95%, D2%, D98% and V95%. Other parameters were also compared such as Integral dose (ID), Homogeneity index (HI) and doses to the organs at risk (OARs). Results: There was no significant difference in the mean dose received by the PTV-Brain or the dose received by 95% and 98% of PTV volume using the two techniques. For PTV-Spine, the percentage volume receiving 95% of the total dose increased significantly in the hybrid IMRT technique compared to the conformal technique. So, hybrid IMRT plan achieved the best coverage for PTV spine. Lower dose for OAR was delivered by 3DCRT, except the heart and thyroid, hybrid IMRT achieved better sparing. All plans resulted in the same dose homogeneity index (DHI) for PTV-Brain. For PTV-Spine, hybrid IMRT technique achieved better dose homogeneity compared to 3DCRT technique (1.09 vs. 1.12;p > 0.05). Conclusions: hybrid IMRT technique can be realized on conformal technique because it achieved better dose coverage for the (PTV) and organ at risk (OAR). 3DCRT reduced mean dose to most OARS, except the heart and thyroid. Therefore, the hybrid IMRT technique may be a CSI treatment alternative to 3DCRT.展开更多
文摘Background Few studies were reported on the comparison of clinical outcomes between intensity-modulated radiotherapy （IMRT） and three-dimensional conformal radiotherapy （3D-CRT） in the treatment of glioblastoma multiforme （GBM）.This study aimed to determine whether IMRT improves clinical outcomes compared with 3D-CRT in patients with GBM.Methods The records of 54 patients with newly-diagnosed GBM from July 2009 to December 2010 were reviewed.The patients underwent postoperative IMRT or 3D-CRT with concurrent and adjuvant temozolomide.Kaplan-Meier method and log rank test were used to estimate differences of patients＇ survival.Results The median follow-up was 13 months.Of the 54 patients,fifty （92.6%） completed the combined modality treatment.The 1-year overall survival rate （OS） was 79.6%.The pattern of failure was predominantly local.A comparative analysis revealed that no statistical difference was observed between the IMRT group （n=21） and the 3D-CRT group （n=33） for 1-year OS （89.6% vs.75.8%,P=0.795）,or 1-year progression-free survival （PFS） （61.0% vs.45.5%,P=0.867）.In dosimetric comparison,IMRT seemed to allow better sparing of organs at risk than 3D-CRT did （P=0.050,P=0.055）.However,there was no significant difference for toxicities of irradiation between the IMRT group and the 3D-CRT group.Conclusions Our preliminary results suggested that delivering standard radiation doses by IMRT is unlikely to improve local control or overall survival for GBM compared with 3D-CRT.Given this lack of survival benefit and increased costs of IMRT,the utilization of IMRT treatment for GBM needs to be carefully rationalized.
文摘AIM To analyse clinical and dosimetric results of helical tomotherapy(HT) and volumetric modulated arc therapy(VMAT) in complex adjuvant breast and nodes irradiation.METHODS Seventy-three patients were included(31 HT and 42 VMAT). Dose were 63.8 Gy(HT) and 63.2 Gy(VMAT) in the tumour bed, 52.2 Gy in the breast, 50.4 Gy in supraclavicular nodes(SCN) and internal mammary chain(IMC) with HT and 52.2 Gy and 49.3 Gy in IMC and SCN with VMAT in 29 fractions. Margins to particle tracking velocimetry were greater in the VMAT cohort(7 mm vs 5 mm).RESULTS For the HT cohort, the coverage of clinical target volumes was as follows: Tumour bed: 99.4% ± 2.4%; breast: 98.4% ± 4.3%; SCN: 99.5% ± 1.2%; IMC:96.5% ± 13.9%. For the VMAT cohort, the coverage was as follows: Tumour bed: 99.7% ± 0.5%, breast: 99.3% ± 0.7%; SCN: 99.6% ± 1.4%; IMC: 99.3% ± 3%. For ipsilateral lung, Dmean and V20 were 13.6 ± 1.2 Gy, 21.1% ± 5%(HT) and 13.6 ± 1.4 Gy, 20.1% ± 3.2%(VMAT). Dmean and V30 of the heart were 7.4 ± 1.4 Gy, 1% ± 1%(HT) and 10.3 ± 4.2 Gy, 2.5% ± 3.9%(VMAT). For controlateral breast Dmean was 3.6 ± 0.2 Gy(HT) and 4.6 ± 0.9 Gy(VMAT). Acute skin toxicity grade 3 was 5% in the two cohorts.CONCLUSION HT and VMAT in complex adjuvant breast irradiation allow a good coverage of target volumes with an acceptable acute tolerance. A longer follow-up is needed to assess the impact of low doses to healthy tissues.
文摘AIM:To assess the feasibility of volumetric intensity-modulated arc radiotherapy (VMAT) in patients with limited polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes syndrome. METHODS:A 70-year-old male with histologically confirmed osteosclerotic myeloma was treated in our department in July 2010 with VMAT. Fourty-six Gray in 23 fractions were given on three bone lesions. Doses delivered to target volume and critical organs were compared with a tridimensional conformal radiotherapy (3D-RT) plan. Treatment was well tolerated without any side effects.RESULTS:VMAT improved dose homogeneity within the target volume, as compared to 3D-RT (standard deviations:2.9 Gy and 1.6 Gy for 3D and VMAT, respectively). VMAT resulted in a better sparing of critical organs. Dose delivered to 20% of organ volume (D20) was reduced from 22 Gy (3D-RT) to 15 Gy (VMAT) for small bowel, from 24 Gy (3D-RT) to 17 Gy (VMAT) for bladder and from 47 Gy (3D-RT) to 3 Gy (VMAT) for spinal cord. Volumes of critical organs that received at least 20 Gy (V20) were decreased by the use of VMAT, as compared to 3D-RT (V20 bladder:10% vs 99%; V20 small bowel:6% vs 21%). One year after treatment completion, no tumor progression has been reported. CONCLUSION:VMAT improved dose distribution as compared to 3D-RT for limited osteosclerotic myeloma, with better saving of critical organs.
基金Supported by Shantou University Medical College Clinical Research Enhancement Initiative,and Research and Travel Grants from the Science and Technology Key Project of Shantou City,China,2012,No.2012-165-131
文摘AIM:To establish the feasibility of simultaneous modulated accelerated radiation therapy(SMART) in esophageal cancer(EC).METHODS:Computed tomography(CT)datasets of 10patients with upper or middle thoracic squamous cell EC undergoing chemoradiotherapy were used to generate SMART,conventionally-fractionated three-dimensional conformal radiotherapy(3DCRT)and intensity-modulated radiation therapy(cf-IMRT)plans,respectively.The gross target volume(GTV)of the esophagus,positive regional lymph nodes(LN),and suspected lymph nodes(LN±)were contoured for each patient.The clinical target volume(CTV)was delineated with 2-cm longitudinal and 0.5-to 1.0-cm radial margins with respect to the GTV and with 0.5-cm uniform margins for LN and LN(±).For the SMART plans,there were two planning target volumes(PTVs):PTV66=(GTV+LN)+0.5 cm and PTV54=CTV+0.5 cm.For the 3DCRT and cfIMRT plans,there was only a single PTV:PTV60=CTV+0.5 cm.The prescribed dose for the SMART plans was 66 Gy/30 F to PTV66 and 54 Gy/30 F to PTV54.The dose prescription to the PTV60 for both the 3DCRT and cf-IMRT plans was set to 60 Gy/30 F.All the plans were generated on the Eclipse 10.0 treatment planning system.Fulfillment of the dose criteria for the PTVs received the highest priority,followed by the spinal cord,heart,and lungs.The dose-volume histograms were compared.RESULTS:Clinically acceptable plans were achieved for all the SMART,cf-IMRT,and 3DCRT plans.Compared with the 3DCRT plans,the SMART plans increased the dose delivered to the primary tumor(66Gy vs 60 Gy),with improved sparing of normal tissues in all patients.The Dmax of the spinal cord,V20 of the lungs,and Dmean and V50 of the heart for the SMART and 3DCRT plans were as follows:38.5±2.0 vs 44.7±0.8(P=0.002),17.1±4.0 vs 25.8±5.0(P=0.000),14.4±7.5 vs 21.4±11.1(P=0.000),and 4.9±3.4vs 12.9±7.6(P=0.000),respectively.In contrast to the cf-IMRT plans,the SMART plans permitted a simultaneous dose escalation(6 Gy)to the primary tumor while demonstrating a significant trend of a lower irradiation dose to all organs at risk except the spinal cord,for which no significant difference was found.CONCLUSION:SMART offers the potential for a 6Gy simultaneous escalation in the irradiation dose delivered to the primary tumor of EC and improves the sparing of normal tissues.
文摘Radiotherapy techniques have substantially improved in the last two decades. After the introduction of 3-dimensional conformal radiotherapy, radiotherapy has been increasingly used for the treatment of hepatocellular carcinoma(HCC). Currently, more advanced techniques, including intensity-modulated radiotherapy(IMRT), stereotactic ablative body radiotherapy(SABR), and charged particle therapy, are used for the treatment of HCC. IMRT can escalate the tumor dose while sparing the normal tissue even though the tumor is large or located near critical organs. SABR can deliver a very high radiation dose to small HCCs in a few fractions, leading to high local control rates of 84%-100%. Various advanced imaging modalities are used for radiotherapy planning and delivery to improve the precision of radiotherapy. These advanced techniques enable the delivery of high dose radiotherapy for early to advanced HCCs without increasing the radiation-induced toxicities. However, as there have been no effective tools for the prediction of the response to radiotherapy or recurrences within or outside the radiation field, future studies should focus on selecting the patients who will benefit from radiotherapy.
文摘Introduction: In medulloblastoma patients craniospinal irradiation is an important element the treatment. Our study aimed to evaluate the effect of absorbed dose to organs at risk using the hybrid intensity-modulated radiation therapy (IMRT) versus three-dimensional conformal radiotherapy (3DCRT) for craniospinal irradiation (CSI) in average risk medulloblastoma patients. Materials and Methods: In this study, thirteen medulloblastoma patients were included. The prescribed total dose to the planning target volume (PTV) was 23, 40 Gy in 13 fractions. Two radiotherapy techniques, three dimensional conformal radiotherapy (3DCRT) and hybrid intensity modulated radiotherapy (IMRT) were used to treat these patients. The coverage of the Target was evaluated using the D mean, D95%, D2%, D98% and V95%. Other parameters were also compared such as Integral dose (ID), Homogeneity index (HI) and doses to the organs at risk (OARs). Results: There was no significant difference in the mean dose received by the PTV-Brain or the dose received by 95% and 98% of PTV volume using the two techniques. For PTV-Spine, the percentage volume receiving 95% of the total dose increased significantly in the hybrid IMRT technique compared to the conformal technique. So, hybrid IMRT plan achieved the best coverage for PTV spine. Lower dose for OAR was delivered by 3DCRT, except the heart and thyroid, hybrid IMRT achieved better sparing. All plans resulted in the same dose homogeneity index (DHI) for PTV-Brain. For PTV-Spine, hybrid IMRT technique achieved better dose homogeneity compared to 3DCRT technique (1.09 vs. 1.12;p > 0.05). Conclusions: hybrid IMRT technique can be realized on conformal technique because it achieved better dose coverage for the (PTV) and organ at risk (OAR). 3DCRT reduced mean dose to most OARS, except the heart and thyroid. Therefore, the hybrid IMRT technique may be a CSI treatment alternative to 3DCRT.
