The Experts below are selected from a list of 138 Experts worldwide ranked by ideXlab platform
A Diaz - One of the best experts on this subject based on the ideXlab platform.
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SU‐GG‐T‐52: Plan Evaluation for Treatment of Malignant Gliomas Using Californium‐252 Neutron Brachytherapy and Compared with SRS
Medical Physics, 2010Co-Authors: Y Liu, A DiazAbstract:Purpose: The objective of this study is to perform a plan evaluation using Californium‐252 neutronbrachytherapy for the treatment of malignant gliomas and compare the neutronbrachytherapy planning with photon Stereotactic Radiosurgery(SRS) therapy planning. Materials/Methods: After a phase I trial of neutronbrachytherapy (Cf‐252 implant) for the treatment of malignant gliomas, there is renewed interest to evaluate the effectiveness of radiation therapy using neutronbrachytherapy compared with SRS. Here we performed a dosimetric comparison of two treatment plans based on the same patient using equivalent prescribed dose. Isodose lines and dose volume histogram of braintumor and adjacent critical structures were used for plan evaluation. Dose of neutronbrachytherapy was calculated using CT‐converted Monte Carlo model and simulated by Monte Carlo code (MCNPX V2.5). The tissue component of Monte Carlo model was adapted from the sectioned images of human cadavers of the Visible Human Project of NLM. Dose of SRS plan was calculated using BrainLab iPlan. A relative biological effectiveness of 6 was used to determine the neutron equivalent dose (ncGy) for central nervous system(CNS)tissues. An equivalent dose of 6000 cGy was prescribed for both plans respectively. Results: The targets were covered by the 95% prescribed dose to 95% tumor volume in both SRS and neutronbrachytherapy plans. Comparing the SRS and Cf‐252 neutronbrachytherapy, the mean dose was 6100 cGy and 6708 ncGy for target, 312 cGy and 177 ncGy for brainstem, 732 cGy and 311 cGy for chiasm, 255 cGy and 275 ncGy for pituitary, and 504 cGy and 420 ncGy for brain, respectively. Conclusions: Cf‐252 Brachytherapy provided conformai dose distribution to the braintumor and reduced the dose to the surrounding critical organs compared to SRS. The implanted Cf‐252 source provides high dose to braintumor and reduces the radiation exposure of normal brain.
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su gg t 52 plan evaluation for treatment of malignant gliomas using Californium 252 neutron brachytherapy and compared with srs
Medical Physics, 2010Co-Authors: Y Liu, A DiazAbstract:Purpose: The objective of this study is to perform a plan evaluation using Californium‐252 neutronbrachytherapy for the treatment of malignant gliomas and compare the neutronbrachytherapy planning with photon Stereotactic Radiosurgery(SRS) therapy planning. Materials/Methods: After a phase I trial of neutronbrachytherapy (Cf‐252 implant) for the treatment of malignant gliomas, there is renewed interest to evaluate the effectiveness of radiation therapy using neutronbrachytherapy compared with SRS. Here we performed a dosimetric comparison of two treatment plans based on the same patient using equivalent prescribed dose. Isodose lines and dose volume histogram of braintumor and adjacent critical structures were used for plan evaluation. Dose of neutronbrachytherapy was calculated using CT‐converted Monte Carlo model and simulated by Monte Carlo code (MCNPX V2.5). The tissue component of Monte Carlo model was adapted from the sectioned images of human cadavers of the Visible Human Project of NLM. Dose of SRS plan was calculated using BrainLab iPlan. A relative biological effectiveness of 6 was used to determine the neutron equivalent dose (ncGy) for central nervous system(CNS)tissues. An equivalent dose of 6000 cGy was prescribed for both plans respectively. Results: The targets were covered by the 95% prescribed dose to 95% tumor volume in both SRS and neutronbrachytherapy plans. Comparing the SRS and Cf‐252 neutronbrachytherapy, the mean dose was 6100 cGy and 6708 ncGy for target, 312 cGy and 177 ncGy for brainstem, 732 cGy and 311 cGy for chiasm, 255 cGy and 275 ncGy for pituitary, and 504 cGy and 420 ncGy for brain, respectively. Conclusions: Cf‐252 Brachytherapy provided conformai dose distribution to the braintumor and reduced the dose to the surrounding critical organs compared to SRS. The implanted Cf‐252 source provides high dose to braintumor and reduces the radiation exposure of normal brain.
Y Liu - One of the best experts on this subject based on the ideXlab platform.
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SU‐GG‐T‐52: Plan Evaluation for Treatment of Malignant Gliomas Using Californium‐252 Neutron Brachytherapy and Compared with SRS
Medical Physics, 2010Co-Authors: Y Liu, A DiazAbstract:Purpose: The objective of this study is to perform a plan evaluation using Californium‐252 neutronbrachytherapy for the treatment of malignant gliomas and compare the neutronbrachytherapy planning with photon Stereotactic Radiosurgery(SRS) therapy planning. Materials/Methods: After a phase I trial of neutronbrachytherapy (Cf‐252 implant) for the treatment of malignant gliomas, there is renewed interest to evaluate the effectiveness of radiation therapy using neutronbrachytherapy compared with SRS. Here we performed a dosimetric comparison of two treatment plans based on the same patient using equivalent prescribed dose. Isodose lines and dose volume histogram of braintumor and adjacent critical structures were used for plan evaluation. Dose of neutronbrachytherapy was calculated using CT‐converted Monte Carlo model and simulated by Monte Carlo code (MCNPX V2.5). The tissue component of Monte Carlo model was adapted from the sectioned images of human cadavers of the Visible Human Project of NLM. Dose of SRS plan was calculated using BrainLab iPlan. A relative biological effectiveness of 6 was used to determine the neutron equivalent dose (ncGy) for central nervous system(CNS)tissues. An equivalent dose of 6000 cGy was prescribed for both plans respectively. Results: The targets were covered by the 95% prescribed dose to 95% tumor volume in both SRS and neutronbrachytherapy plans. Comparing the SRS and Cf‐252 neutronbrachytherapy, the mean dose was 6100 cGy and 6708 ncGy for target, 312 cGy and 177 ncGy for brainstem, 732 cGy and 311 cGy for chiasm, 255 cGy and 275 ncGy for pituitary, and 504 cGy and 420 ncGy for brain, respectively. Conclusions: Cf‐252 Brachytherapy provided conformai dose distribution to the braintumor and reduced the dose to the surrounding critical organs compared to SRS. The implanted Cf‐252 source provides high dose to braintumor and reduces the radiation exposure of normal brain.
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su gg t 52 plan evaluation for treatment of malignant gliomas using Californium 252 neutron brachytherapy and compared with srs
Medical Physics, 2010Co-Authors: Y Liu, A DiazAbstract:Purpose: The objective of this study is to perform a plan evaluation using Californium‐252 neutronbrachytherapy for the treatment of malignant gliomas and compare the neutronbrachytherapy planning with photon Stereotactic Radiosurgery(SRS) therapy planning. Materials/Methods: After a phase I trial of neutronbrachytherapy (Cf‐252 implant) for the treatment of malignant gliomas, there is renewed interest to evaluate the effectiveness of radiation therapy using neutronbrachytherapy compared with SRS. Here we performed a dosimetric comparison of two treatment plans based on the same patient using equivalent prescribed dose. Isodose lines and dose volume histogram of braintumor and adjacent critical structures were used for plan evaluation. Dose of neutronbrachytherapy was calculated using CT‐converted Monte Carlo model and simulated by Monte Carlo code (MCNPX V2.5). The tissue component of Monte Carlo model was adapted from the sectioned images of human cadavers of the Visible Human Project of NLM. Dose of SRS plan was calculated using BrainLab iPlan. A relative biological effectiveness of 6 was used to determine the neutron equivalent dose (ncGy) for central nervous system(CNS)tissues. An equivalent dose of 6000 cGy was prescribed for both plans respectively. Results: The targets were covered by the 95% prescribed dose to 95% tumor volume in both SRS and neutronbrachytherapy plans. Comparing the SRS and Cf‐252 neutronbrachytherapy, the mean dose was 6100 cGy and 6708 ncGy for target, 312 cGy and 177 ncGy for brainstem, 732 cGy and 311 cGy for chiasm, 255 cGy and 275 ncGy for pituitary, and 504 cGy and 420 ncGy for brain, respectively. Conclusions: Cf‐252 Brachytherapy provided conformai dose distribution to the braintumor and reduced the dose to the surrounding critical organs compared to SRS. The implanted Cf‐252 source provides high dose to braintumor and reduces the radiation exposure of normal brain.
Jia Zhang - One of the best experts on this subject based on the ideXlab platform.
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External beam radiotherapy with or without Californium-252 neutron brachytherapy for treatment of recurrence after definitive chemoradiotherapy.
Scientific reports, 2020Co-Authors: Yi-ping Yang, Jing Liang, Jin Zhao, Jian-sheng Wang, Jia ZhangAbstract:We aimed to evaluate the application of external beam radiotherapy (EBRT) combined with Californium-252 (252Cf) neutron intraluminal brachytherapy (NBT) in patients with local recurrent esophageal cancer after definitive chemoradiotherapy (CRT). Sixty-two patients with local recurrent esophageal squamous cell carcinoma after definitive CRT were retrospectively analyzed; 31 patients underwent NBT+EBRT, and 31 received EBRT alone. The response rate; 1-, 2-, and 3-year overall survival rates; and adverse event occurrence rates were compared between these two patient groups. The response rate was 83.87% (26/31) in the NBT+EBRT group and 67.74% (21/31) in the EBRT group (p
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external beam radiotherapy with or without Californium 252 neutron brachytherapy for treatment of recurrence after definitive chemoradiotherapy
Scientific Reports, 2020Co-Authors: Yi-ping Yang, Jing Liang, Jin Zhao, Jian-sheng Wang, Jia ZhangAbstract:We aimed to evaluate the application of external beam radiotherapy (EBRT) combined with Californium-252 (252Cf) neutron intraluminal brachytherapy (NBT) in patients with local recurrent esophageal cancer after definitive chemoradiotherapy (CRT). Sixty-two patients with local recurrent esophageal squamous cell carcinoma after definitive CRT were retrospectively analyzed; 31 patients underwent NBT+EBRT, and 31 received EBRT alone. The response rate; 1-, 2-, and 3-year overall survival rates; and adverse event occurrence rates were compared between these two patient groups. The response rate was 83.87% (26/31) in the NBT+EBRT group and 67.74% (21/31) in the EBRT group (p < 0.001). The 1-, 2-, and 3-year overall survival rates were 80.6%, 32.3%, and 6.5%, respectively, in the EBRT group, with a median survival time of 18 months. The 1-, 2-, and 3-year overall survival rates were 83.8%, 41.9%, and 6.9%, respectively, in the NBT+EBRT group, with a median survival time of 19 months. The differences between the groups were not significant (p = 0.352). Regarding acute toxicity, no incidences of fistula or massive bleeding were observed during the treatment period. The incidences of severe and late complications were not significantly different between the two groups (p = 0.080). However, the causes of death for all patients differed between the groups. Our data indicate that 252Cf-NBT+EBRT produces favorable local control for patients with local recurrent esophageal cancer after CRT, with tolerable side effects.
Xin Lei - One of the best experts on this subject based on the ideXlab platform.
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Californium 252 neutron intracavity brachytherapy alone for t1n0 low lying rectal adenocarcinoma a definitive anal sphincter preserving radiotherapy
Scientific Reports, 2017Co-Authors: Yanli Xiong, Kewei Zhao, Qian Zhou, Jinlu Shan, Jia Liu, Shu Chen, Mei Yang, Xin LeiAbstract:This study evaluated the 4-year results of 32 patients with T1N0 low-lying rectal adenocarcinoma treated solely with Californium-252 (Cf-252) neutron intracavity brachytherapy (ICBT). Patients were solicited into the study from January 2008 to June 2011. All the patients had refused surgery or surgery was contraindicated. The patients were treated with Cf-252 neutron ICBT using a novel 3.5-cm diameter off-axis 4-channel intrarectal applicator designed by the authors. The dose reference point was defined on the mucosa surface, with a total dose of 55–62 Gy-eq/4 f (13–16 Gy-eq/f/wk). All the patients completed the radiotherapy in accordance with our protocol. The rectal lesions regressed completely, and the acute rectal toxicity was mild (≤G2). The 4-year local control, overall survival, disease-free survival, and late complication (≥G2) rates were 96.9%, 90.6%, 87.5% and 15.6%, respectively. No severe late complication (≥G3) occurred. The mean follow-up was 56.1 ± 16.0 months. At the end of last follow-up, 29 patients remained alive. The mean survival time was 82.1 ± 2.7 months. Cf-252 neutron ICBT administered as the sole treatment (without surgery) for patients with T1N0 low-lying rectal adenocarcinoma is effective with acceptable late complications. Our study and method offers a definitive anal sphincter-preserving radiotherapy for T1N0 low-lying rectal adenocarcinoma patients.
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Paired observation of Californium-252 neutron intraluminal brachytherapy combined with external-beam radiotherapy with and without lead shielding for cervical cancer
Chinese Journal of Radiation Oncology, 2015Co-Authors: Zhuojie Dai, Xin Lei, Yonghong ChenAbstract:Objective To compare the efficacy between Californium-252(252Cf)neutron intraluminal brachytherapy combined with external-beam radiotherapy with lead-shielding pelvic parallel opposing field technique and non-lead-shielding four-field box technique for cervical cancer. Methods A total of 52 patients with stage Ⅱa-Ⅲb cervical squamous cell carcinoma who were admitted to our hospital from 2004 to 2007 were enrolled as subjects and paired by clinical stage, age, tumor size, and degree of anemia. The 26 pairs of patients were divided into lead-shielding pelvic parallel opposing field group(lead-shielding group)and non-lead-shielding four-field box group(non-lead-shielding group). For all patients in both groups, 252Cf neutron brachytherapy was added in external-beam radiotherapy. The local control(LC), overall survival(OS), and disease-free survival(DFS)rates were calculated using the Kaplan-Meier method and analyzed using the log-rank test. The difference in the incidence of late complications was analyzed using the McNemar method. Results There were significant differences in 5-year LC, OS, and DFS rates between the lead-shielding group and the non-lead-shielding group(85% vs. 81%,P=0.014; 89% vs. 73%, P= 0.013; 89% vs. 73%, P= 0.013). There was also significant difference in the incidence of late complications between the lead-shielding group and the non-lead-shielding group(12% vs. 23%, P= 0. 008). Conclusions When intraluminal brachytherapy combined with external-beam radiotherapy is used to treat cervical cancer, the centers of the front and back fields should be shielded by lead, regardless of whether the parallel opposing field technique or the four-field box technique is used. Key words: Cervical neoplasms/radiotherapy; Radiotherapy, external beam radiation; Radiotherapy, 252Cf neutron; Lead shielding
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Californium 252 brachytherapy combined with external beam radiotherapy for cervical cancer long term treatment results
International Journal of Radiation Oncology Biology Physics, 2011Co-Authors: Xin Lei, Chengyuan Qian, Yi Qing, Kewei Zhao, Zhengzhou Yang, Nan Dai, Zhaoyang Zhong, Cheng Tang, Qian Zhou, Yan FengAbstract:Purpose To observe, by retrospective analysis, the curative effects and complications due to Californium-252 ( 252 Cf) neutron intracavitary brachytherapy (ICBT) combined with external-beam radiotherapy (EBRT) in the treatment of cervical cancer. Methods and Materials From February 1999 to December 2007, 696 patients with cervical cancer (Stages IB to IIIB) were treated with 252 Cf-ICBT in combination of EBRT. Of all, 31 patients were at Stage IB, 104 at IIA, 363 at IIB, 64 at IIIA, and 134 at IIIB. Californium-252 ICBT was delivered at 7–12 Gy per insertion per week, with a total dose of 29–45 Gy to reference point A in three to five insertions. The whole pelvic cavity was treated with 8-MV X-ray external irradiation at 2 Gy per fraction, four times per week. After 16–38 Gy of external irradiation, the center of the whole pelvic field was blocked with a 4-cm-wide lead shield, with a total external irradiation dose of 44–56 Gy. The total treatment course was 5 to 6 weeks. Results Overall survival rate at 3 and 5 years for all patients was 76.0% and 64.9%, respectively. Disease-free 3- and 5-year survival rates of patients were 71.2% and 58.4%, respectively. Late complications included vaginal contracture and adhesion, radiation proctitis, radiation cystitis, and inflammatory bowel, which accounted for 5.8%, 7.1%, 6.2%, and 4.9%, respectively. Univariate analysis results showed significant correlation of stage, age, histopathologic grade, and lymph node status with overall survival. Cox multiple regression analysis showed that the independent variables were stage, histopathologic grade, tumor size, and lymphatic metastasis in all patients. Conclusion Results of this series suggest that the combined use of 252 Cf-ICBT with EBRT is an effective method for treatment of cervical cancer.
Yan Feng - One of the best experts on this subject based on the ideXlab platform.
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Californium 252 brachytherapy combined with external beam radiotherapy for cervical cancer long term treatment results
International Journal of Radiation Oncology Biology Physics, 2011Co-Authors: Xin Lei, Chengyuan Qian, Yi Qing, Kewei Zhao, Zhengzhou Yang, Nan Dai, Zhaoyang Zhong, Cheng Tang, Qian Zhou, Yan FengAbstract:Purpose To observe, by retrospective analysis, the curative effects and complications due to Californium-252 ( 252 Cf) neutron intracavitary brachytherapy (ICBT) combined with external-beam radiotherapy (EBRT) in the treatment of cervical cancer. Methods and Materials From February 1999 to December 2007, 696 patients with cervical cancer (Stages IB to IIIB) were treated with 252 Cf-ICBT in combination of EBRT. Of all, 31 patients were at Stage IB, 104 at IIA, 363 at IIB, 64 at IIIA, and 134 at IIIB. Californium-252 ICBT was delivered at 7–12 Gy per insertion per week, with a total dose of 29–45 Gy to reference point A in three to five insertions. The whole pelvic cavity was treated with 8-MV X-ray external irradiation at 2 Gy per fraction, four times per week. After 16–38 Gy of external irradiation, the center of the whole pelvic field was blocked with a 4-cm-wide lead shield, with a total external irradiation dose of 44–56 Gy. The total treatment course was 5 to 6 weeks. Results Overall survival rate at 3 and 5 years for all patients was 76.0% and 64.9%, respectively. Disease-free 3- and 5-year survival rates of patients were 71.2% and 58.4%, respectively. Late complications included vaginal contracture and adhesion, radiation proctitis, radiation cystitis, and inflammatory bowel, which accounted for 5.8%, 7.1%, 6.2%, and 4.9%, respectively. Univariate analysis results showed significant correlation of stage, age, histopathologic grade, and lymph node status with overall survival. Cox multiple regression analysis showed that the independent variables were stage, histopathologic grade, tumor size, and lymphatic metastasis in all patients. Conclusion Results of this series suggest that the combined use of 252 Cf-ICBT with EBRT is an effective method for treatment of cervical cancer.
