Transarterial radioembolization(TARE) is a form of brachytherapy in which intra-arterially injected yttrium-90-loaded microspheres serve as a source for internal radiation purposes.On the average,it produces disease c...Transarterial radioembolization(TARE) is a form of brachytherapy in which intra-arterially injected yttrium-90-loaded microspheres serve as a source for internal radiation purposes.On the average,it produces disease control rates exceeding 80% and it is a consolidated therapy for hepatocellular carcinoma(HCC);however,current data are all based on retrospective series or non-controlled prospective studies since randomized controlled trials comparing it with the other liver-directed therapies for intermediate and locally advanced stage HCC are still underway.The data available show that TARE provides similar or even better survival rates when compared to transarterial chemoembolization(TACE).First-line TARE is best indicated for both intermediatestage patients(staged according to the barcelona clinic liver cancer staging classification) who have lesions which respond poorly to TACE due to multiple tumors or a large tumor burden,and for locally advanced-stage patients with solitary tumors,and segmental or lobar portal vein tumor thrombosis.In addition,emerging data have suggested the use of TARE in patients who are classified slightly beyond the Milan criteria regarding radical treatment for downstaging purposes.As a secondline treatment,TARE can also be applied in patients progressing to TACE or sorafenib;a large number of phase Ⅱ/Ⅲ trials are ongoing with the purpose of evaluating the best association with systemic therapies.Transarterial radioembolization is very well tolerated and has a low rate of complications which are mainly related to unintended non-target tissue irradiation,including the surrounding liver parenchyma.The complications can be additionally reduced by accurate patient selection and a strict pre-treatment evaluation including dosimetry and assessment of the vascular anatomy.Since a correct treatment algorithm for potential TARE candidates is not clear and standardized,this comprehensive review analyzes the best selection criteria for patients who really benefit from TARE and also the new advances of this therapy,which can be a very important weapon against HCC.展开更多
To evaluate the efficacy and feasibility of external beam radiotherapy(EBRT)for duodenal adenocarcinoma in an 84-year-old female who underwent EBRT(2.2 Gy/d for a total dose of 46.2 Gy)using helical tomotherapy(HT).To...To evaluate the efficacy and feasibility of external beam radiotherapy(EBRT)for duodenal adenocarcinoma in an 84-year-old female who underwent EBRT(2.2 Gy/d for a total dose of 46.2 Gy)using helical tomotherapy(HT).Toxicity was evaluated on the National Cancer Institute's common toxicity criteria(CTCAE 3.0).The patient completed the treatment without G3-G4 toxicity.After 22-mo follow-up,she is alive and well,in complete remission with no late side effects.HT seems to be feasible and effective for duodenal adenocarcinoma in old to very old patients.展开更多
<div style="text-align:justify;"> <strong><span style="font-family:Verdana;">Background:</span></strong><span style="font-family:Verdana;"> Intensity M...<div style="text-align:justify;"> <strong><span style="font-family:Verdana;">Background:</span></strong><span style="font-family:Verdana;"> Intensity Modulated Radiation Therapy (IMRT) is currently employed as a major arm of treatment in multiforme glioblastoma (GBM). The present study aimed to compare 3D-CRT with IMRT to assess tumor volume coverage and OAR sparing for </span><span style="font-family:Verdana;">the </span><span "=""><span style="font-family:Verdana;">treatment of malignant gliomas. </span><b><span style="font-family:Verdana;">Materials</span></b> <b><span style="font-family:Verdana;">and</span></b> <b><span style="font-family:Verdana;">methods:</span></b><span style="font-family:Verdana;"> We assessed 22 anonymized patients datasets with High Grade Glioblastoma who had undergone post</span></span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">operative Intensity Modulated Radiotherapy (IMRT) and 3D Conformal Radiotherapy (3D-CRT), This study will compare and contrast treatment plans Rapidarc and 3D-CRT to determine w</span><span style="font-family:Verdana;">h</span><span style="font-family:Verdana;">ich techn</span><span style="font-family:Verdana;">ology</span><span "=""><span style="font-family:Verdana;"> improves significantly dosimetric parameters. </span><b><span style="font-family:Verdana;">Results:</span></b><span style="font-family:Verdana;"> Plans will be assessed by reviewing the coverage of the PTV using mean, maximum and minimum doses while the OAR doses will be compared using the maximal doses for each, as set out in the QUANTEC dose limits. </span><b><span style="font-family:Verdana;">Conclusion:</span></b><span style="font-family:Verdana;"> The use of IMRT seems a superior technique as compared to 3D-CRT for the treatment of malignant gliomas having the potential to increase </span></span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">dose to the PTV while sparing OARs optimally.</span> </div>展开更多
Relative biological effectiveness (RBE) is an important quantity in planning particle beam cancer therapy. In general, the RBE describes the biological effectiveness of a given primary beam with respect to a reference...Relative biological effectiveness (RBE) is an important quantity in planning particle beam cancer therapy. In general, the RBE describes the biological effectiveness of a given primary beam with respect to a reference photon irradiation. RBE varies not only for different primary beams but also with depth in the target for a given beam modality. It is not a quantity that easily lends itself to measurements or computation as it depends on many biological and physical quantities. Numerous experiments in vitro using various cell lines and irradiation modalities have shown that a general relationship between RBE and the physical quantity Linear Energy Transfer (LET) exists. Several groups have proposed including LET in the radiation therapy treatment planning instead of the more complicated and elusive RBE. It has been shown that LET is an important quantity to consider in treating radio-resistant tumors. The concept of LET painting has been proposed with the goal of improving tumor control probability (TCP) for hypoxic tumors by focusing high LET radiation on the hypoxic region of the tumor while restricting the surrounding normal tissue to low LET radiation. In order to properly incorporate LET in clinical treatment, it is important to be able to experimentally measure and verify LET distribution. We propose a novel method for measuring LET using a dual chamber methodology exploiting the difference in the observed recombination between air filled ionization chambers (IC) and liquid filled ionization chambers (LIC). The resulting difference in the measured signals will be used to directly extract the relative LET of an actual treatment beam in real time. This paper describes our initial studies of this method, presents preliminary results, and discusses further improvements toward a practical real-time LET measuring device.展开更多
Purpose: To investigate a genetic algorithm approach to automatic treatment planning. Methods: A Python script based on genetic algorithm (GA) was implemented for VMAT treatment planning of prostate tumor. The script ...Purpose: To investigate a genetic algorithm approach to automatic treatment planning. Methods: A Python script based on genetic algorithm (GA) was implemented for VMAT treatment planning of prostate tumor. The script was implemented in RayStation treatment planning system using Python code. Two different clinical prescriptions were considered: 78 Gy prescribed to planning target volume in 39 fractions (GROUP 1) and simultaneous integrated boost (70.2 Gy to prostate bed and 61.1 Gy to seminal vesicles) in 26 fractions (GROUP 2). The script automatically optimizes doses to PTV and OARs according to GA. A comparison with corresponding plans created with Monaco TPS (M) and Auto-Planning module of Pinnacle3 (AP) was carried out. The plans were evaluated with a total score (TS) of PlanIQ software in terms of target coverage and sparing of OARs as well as clinical score (CS) performed by a Radiation Oncologist. Results: In GROUP 1, mean value of TS were 150.6 ± 30.7, 146.3 ± 36.1 and 137.4 ± 35.7 for AP, GA and M respectively. For GROUP 2, mean value for TS were 163.5 ± 16.8, 163.4 ± 24.7 and 162.9 ± 16.6 for AP, GA and M respectively with no significance differences. In terms of CS, the highest value has been attributed to GA in four patients out of five for both GROUP 1 and 2. Conclusions: Genetic approach is practicable for prostate VMAT plan generation and studies are underway in other anatomical sites such as Head and Neck and Rectum.展开更多
Primary hypothyroidism commonly occurs after radiotherapy(RT),and coincides with increased circulating thyroid-stimulating hormone(TSH)levels.We tested therefore the protective effect of suppressing TSH with L-thyroxi...Primary hypothyroidism commonly occurs after radiotherapy(RT),and coincides with increased circulating thyroid-stimulating hormone(TSH)levels.We tested therefore the protective effect of suppressing TSH with L-thyroxine during RT for medulloblastoma/PNET and Hodgkin lymphoma(HL)in a prospective cohort study.From 1998 to 2001,a total of 37 euthyroid children with medulloblastoma/PNET plus 14 with HL,scheduled for craniospinal irradiation and mediastinum/neck radiotherapy,respectively,underwent thyroid ultrasound and free triiodothyronine(FT3),free thyroxine(FT4),and TSH evaluation at the beginning and end of craniospinal iiradiation.From 14 days before and up to the end of radiotherapy,patients were administered L-thyroxine checking every 3 days TSH to ensure a value<0.3μIU/mL.During follow-up,blood tests and ultrasound were repeated;primary hypothyroidism was considered an increased TSH level greater than normal range.Twenty-two/37 patients with medulloblastoma/PNET and all the 14 patients with HL were alive after a median 231 months from radiotherapy with 7/22 and 8/14 having correctly reached TSH levels˂0.3μIU/mL and well matched for other variables.Twenty years on,hypothyroidism-free survival rates differed significantly,being 60%±15%and 15.6%±8.2%in TSH-suppressed vs.not-TSH suppressed patients,respectively(P=0.001).These findings suggest that hypothyroidism could be durably prevented in two populations at risk of late RT sequelae,but it should be confirmed in a larger cohort.展开更多
The morphology characteristics of cell apoptosis of the malignant tumour cells in magnetic field-treated mouse was observed for the first time. The apoptotic cancer cell contracted, became rounder and divorced from ad...The morphology characteristics of cell apoptosis of the malignant tumour cells in magnetic field-treated mouse was observed for the first time. The apoptotic cancer cell contracted, became rounder and divorced from adjacent cells; the heterochromatin condensed and coagulated together along the inner side of the nuclear membrane; the endoplasmic reticulums(ER) expanded and fused with the cellular membrane; many apoptotic bodies which were packed by the cellular membrane appeared and were devoured by some lymphocytes and plasma. Apoptosis of cancer cells was detected by terminal deoxynucleotidyl transferase mediated in situ nick end labeling(TUNEL). It was found that the number of apoptosis cancer cells of the sample treated by the magnetic field is more than that of the control sample. The growth of malignant tumour in mice was inhibited and the ability of immune cell to dissolve cancer cells was improved by ultralow frequency(ULF) pulsed gradient magnetic field; the nuclei DNA contents decreased, indicating that magnetic field can block DNA replication and inhibit mitosis of cancer cells. It was suggested that magnetic field could inhibit the metabolism of cancer cell, lower its malignancy, and restrain its rapid and heteromorphic growth. Since ULF pulsed gradient magnetic field can induce apoptosis of cancer cells and inhibit the growth of malignant tumour, it could be used as a new method to treat cancer.展开更多
文摘Transarterial radioembolization(TARE) is a form of brachytherapy in which intra-arterially injected yttrium-90-loaded microspheres serve as a source for internal radiation purposes.On the average,it produces disease control rates exceeding 80% and it is a consolidated therapy for hepatocellular carcinoma(HCC);however,current data are all based on retrospective series or non-controlled prospective studies since randomized controlled trials comparing it with the other liver-directed therapies for intermediate and locally advanced stage HCC are still underway.The data available show that TARE provides similar or even better survival rates when compared to transarterial chemoembolization(TACE).First-line TARE is best indicated for both intermediatestage patients(staged according to the barcelona clinic liver cancer staging classification) who have lesions which respond poorly to TACE due to multiple tumors or a large tumor burden,and for locally advanced-stage patients with solitary tumors,and segmental or lobar portal vein tumor thrombosis.In addition,emerging data have suggested the use of TARE in patients who are classified slightly beyond the Milan criteria regarding radical treatment for downstaging purposes.As a secondline treatment,TARE can also be applied in patients progressing to TACE or sorafenib;a large number of phase Ⅱ/Ⅲ trials are ongoing with the purpose of evaluating the best association with systemic therapies.Transarterial radioembolization is very well tolerated and has a low rate of complications which are mainly related to unintended non-target tissue irradiation,including the surrounding liver parenchyma.The complications can be additionally reduced by accurate patient selection and a strict pre-treatment evaluation including dosimetry and assessment of the vascular anatomy.Since a correct treatment algorithm for potential TARE candidates is not clear and standardized,this comprehensive review analyzes the best selection criteria for patients who really benefit from TARE and also the new advances of this therapy,which can be a very important weapon against HCC.
文摘To evaluate the efficacy and feasibility of external beam radiotherapy(EBRT)for duodenal adenocarcinoma in an 84-year-old female who underwent EBRT(2.2 Gy/d for a total dose of 46.2 Gy)using helical tomotherapy(HT).Toxicity was evaluated on the National Cancer Institute's common toxicity criteria(CTCAE 3.0).The patient completed the treatment without G3-G4 toxicity.After 22-mo follow-up,she is alive and well,in complete remission with no late side effects.HT seems to be feasible and effective for duodenal adenocarcinoma in old to very old patients.
文摘<div style="text-align:justify;"> <strong><span style="font-family:Verdana;">Background:</span></strong><span style="font-family:Verdana;"> Intensity Modulated Radiation Therapy (IMRT) is currently employed as a major arm of treatment in multiforme glioblastoma (GBM). The present study aimed to compare 3D-CRT with IMRT to assess tumor volume coverage and OAR sparing for </span><span style="font-family:Verdana;">the </span><span "=""><span style="font-family:Verdana;">treatment of malignant gliomas. </span><b><span style="font-family:Verdana;">Materials</span></b> <b><span style="font-family:Verdana;">and</span></b> <b><span style="font-family:Verdana;">methods:</span></b><span style="font-family:Verdana;"> We assessed 22 anonymized patients datasets with High Grade Glioblastoma who had undergone post</span></span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">operative Intensity Modulated Radiotherapy (IMRT) and 3D Conformal Radiotherapy (3D-CRT), This study will compare and contrast treatment plans Rapidarc and 3D-CRT to determine w</span><span style="font-family:Verdana;">h</span><span style="font-family:Verdana;">ich techn</span><span style="font-family:Verdana;">ology</span><span "=""><span style="font-family:Verdana;"> improves significantly dosimetric parameters. </span><b><span style="font-family:Verdana;">Results:</span></b><span style="font-family:Verdana;"> Plans will be assessed by reviewing the coverage of the PTV using mean, maximum and minimum doses while the OAR doses will be compared using the maximal doses for each, as set out in the QUANTEC dose limits. </span><b><span style="font-family:Verdana;">Conclusion:</span></b><span style="font-family:Verdana;"> The use of IMRT seems a superior technique as compared to 3D-CRT for the treatment of malignant gliomas having the potential to increase </span></span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">dose to the PTV while sparing OARs optimally.</span> </div>
文摘Relative biological effectiveness (RBE) is an important quantity in planning particle beam cancer therapy. In general, the RBE describes the biological effectiveness of a given primary beam with respect to a reference photon irradiation. RBE varies not only for different primary beams but also with depth in the target for a given beam modality. It is not a quantity that easily lends itself to measurements or computation as it depends on many biological and physical quantities. Numerous experiments in vitro using various cell lines and irradiation modalities have shown that a general relationship between RBE and the physical quantity Linear Energy Transfer (LET) exists. Several groups have proposed including LET in the radiation therapy treatment planning instead of the more complicated and elusive RBE. It has been shown that LET is an important quantity to consider in treating radio-resistant tumors. The concept of LET painting has been proposed with the goal of improving tumor control probability (TCP) for hypoxic tumors by focusing high LET radiation on the hypoxic region of the tumor while restricting the surrounding normal tissue to low LET radiation. In order to properly incorporate LET in clinical treatment, it is important to be able to experimentally measure and verify LET distribution. We propose a novel method for measuring LET using a dual chamber methodology exploiting the difference in the observed recombination between air filled ionization chambers (IC) and liquid filled ionization chambers (LIC). The resulting difference in the measured signals will be used to directly extract the relative LET of an actual treatment beam in real time. This paper describes our initial studies of this method, presents preliminary results, and discusses further improvements toward a practical real-time LET measuring device.
文摘Purpose: To investigate a genetic algorithm approach to automatic treatment planning. Methods: A Python script based on genetic algorithm (GA) was implemented for VMAT treatment planning of prostate tumor. The script was implemented in RayStation treatment planning system using Python code. Two different clinical prescriptions were considered: 78 Gy prescribed to planning target volume in 39 fractions (GROUP 1) and simultaneous integrated boost (70.2 Gy to prostate bed and 61.1 Gy to seminal vesicles) in 26 fractions (GROUP 2). The script automatically optimizes doses to PTV and OARs according to GA. A comparison with corresponding plans created with Monaco TPS (M) and Auto-Planning module of Pinnacle3 (AP) was carried out. The plans were evaluated with a total score (TS) of PlanIQ software in terms of target coverage and sparing of OARs as well as clinical score (CS) performed by a Radiation Oncologist. Results: In GROUP 1, mean value of TS were 150.6 ± 30.7, 146.3 ± 36.1 and 137.4 ± 35.7 for AP, GA and M respectively. For GROUP 2, mean value for TS were 163.5 ± 16.8, 163.4 ± 24.7 and 162.9 ± 16.6 for AP, GA and M respectively with no significance differences. In terms of CS, the highest value has been attributed to GA in four patients out of five for both GROUP 1 and 2. Conclusions: Genetic approach is practicable for prostate VMAT plan generation and studies are underway in other anatomical sites such as Head and Neck and Rectum.
文摘Primary hypothyroidism commonly occurs after radiotherapy(RT),and coincides with increased circulating thyroid-stimulating hormone(TSH)levels.We tested therefore the protective effect of suppressing TSH with L-thyroxine during RT for medulloblastoma/PNET and Hodgkin lymphoma(HL)in a prospective cohort study.From 1998 to 2001,a total of 37 euthyroid children with medulloblastoma/PNET plus 14 with HL,scheduled for craniospinal irradiation and mediastinum/neck radiotherapy,respectively,underwent thyroid ultrasound and free triiodothyronine(FT3),free thyroxine(FT4),and TSH evaluation at the beginning and end of craniospinal iiradiation.From 14 days before and up to the end of radiotherapy,patients were administered L-thyroxine checking every 3 days TSH to ensure a value<0.3μIU/mL.During follow-up,blood tests and ultrasound were repeated;primary hypothyroidism was considered an increased TSH level greater than normal range.Twenty-two/37 patients with medulloblastoma/PNET and all the 14 patients with HL were alive after a median 231 months from radiotherapy with 7/22 and 8/14 having correctly reached TSH levels˂0.3μIU/mL and well matched for other variables.Twenty years on,hypothyroidism-free survival rates differed significantly,being 60%±15%and 15.6%±8.2%in TSH-suppressed vs.not-TSH suppressed patients,respectively(P=0.001).These findings suggest that hypothyroidism could be durably prevented in two populations at risk of late RT sequelae,but it should be confirmed in a larger cohort.
基金The authors thank Prof. Li Tongping of the Pathological Unit of Fundamental Medical School,Tongji Medical University for his kind instruction and help. This work was supported by the National Natural Science Foundation of China(Grant No. 39870823) and
文摘The morphology characteristics of cell apoptosis of the malignant tumour cells in magnetic field-treated mouse was observed for the first time. The apoptotic cancer cell contracted, became rounder and divorced from adjacent cells; the heterochromatin condensed and coagulated together along the inner side of the nuclear membrane; the endoplasmic reticulums(ER) expanded and fused with the cellular membrane; many apoptotic bodies which were packed by the cellular membrane appeared and were devoured by some lymphocytes and plasma. Apoptosis of cancer cells was detected by terminal deoxynucleotidyl transferase mediated in situ nick end labeling(TUNEL). It was found that the number of apoptosis cancer cells of the sample treated by the magnetic field is more than that of the control sample. The growth of malignant tumour in mice was inhibited and the ability of immune cell to dissolve cancer cells was improved by ultralow frequency(ULF) pulsed gradient magnetic field; the nuclei DNA contents decreased, indicating that magnetic field can block DNA replication and inhibit mitosis of cancer cells. It was suggested that magnetic field could inhibit the metabolism of cancer cell, lower its malignancy, and restrain its rapid and heteromorphic growth. Since ULF pulsed gradient magnetic field can induce apoptosis of cancer cells and inhibit the growth of malignant tumour, it could be used as a new method to treat cancer.
