1.The model training of knowledge-based radiotherapy treatment planning and its preliminary application
Fan JIANG ; Yibao ZHANG ; Haizhen YUE ; Qiaoqiao HU ; Hao WU
Chinese Journal of Radiation Oncology 2016;25(11):1223-1227
Objective Knowledge?based radiotherapy ( KBRT ) can reduce the plan quality variability induced by different experiences between physicians and improve the quality of treatment plans. Methods The Varian Rapid Plan system was used to train a dose?volume histogram ( DVH) prediction model. The obtained model was preliminarily applied to semi?automatic design of the preoperative treatment plans for rectal cancer. Eighty high?quality volumetric modulated arc therapy plans were imported into the model training set of the Rapid Plan system. The structures of the plans were matched to the corresponding labels and codes as listed in the library. The training started after the verification of prescription. The residual plots,regression curves,geometric plots for organ at risk ( OAR) ,in?field DVH plots,and model training logs were examined. After removal of the mismatch, the original plans were assessed to rule out outliers and influential data points. More similar plans may be added for another round of training. Ten KBRT plans were designed using the final model and compared with the clinical plans. Results For the two major OARs,the femoral head and bladder,the average goodness of fit of the principal component were 0?999 415/1.0 and 0?999 963/1.0 for the DVH model,and 0?999 651/1.0 and 0?999 945/1.0 for geometry?based expected dose model,respectively. In all the plans, 11 had Cook ’ s distance values exceeding the tolerance and 4 had studentized residual values exceeding the tolerance. The outliers were all kept in the training set to generalize the scope of the model. The 10 KBRT plans had significantly improved homogeneity indices for PGTV and PTV than the original plans (P=0?00,0?04).The 10 KBRT plans also had significantly reduced D50% to the femoral head and bladder as well as significantly reduced mean doses to the bladder than the original plans (P=0?042,0?000,0?005). Conclusions In this study,the Rapid Plan system is used to train a KBRT model for design of preoperative radiotherapy plans for rectal cancer. The results of preliminary application meet the clinical requirements.
2.Knowledge-based semi-automated optimization of intensity-modulated radiotherapy plans using a volume modulated arc therapy-configured model
Yibao ZHANG ; Fan JIANG ; Haizhen YUE ; Qiaoqiao HU ; Jian ZHANG ; Jian GONG ; Hao WU
Chinese Journal of Radiation Oncology 2017;26(2):178-181
Objective To evaluate the feasibility and dosimetric features of a volume modulated arc therapy (VMAT)-configured model in knowledge-based optimization of fixed-field dynamic intensitymodulated radiotherapy (IMRT) plans based on the Varian RapidPlan system.Methods ① A dose-volume histogram prediction model was trained with 81 qualified preoperative VMAT plans for rectal cancer and then statistically verified.② For clinically approved 10 IMRT plans with the same dose prescription,the above model was used to automatically generate new optimization parameters and dynamic muhileaf collimator (MLC) sequences with field geometry and beam energy unchanged.③ In order to rule out the disparities between different versions,a single algorithm was used to calculate the absolute doses of the original and new plans.④ Statistical analyses were performed on dosimetric parameters after comparable target dose coverage was achieved in the two plans by appropriate normalization.Results On the basis of similar target dose homogeneity and coverage,RapidPlan significantly reduced the doses to the urinary bladder (D50% by 9.01 Gy,P =0.000;Dmean by 8.08 Gy,P =0.005) and the femoral head (D50% by 4.20 Gy,P =0.000;Dmean by 3.84 Gy,P=0.005) but significantly elevated the mean total number of monitor units (1211±99 vs.771±79,P=0.000) and the number of fields with multiple MLC carriage groups.The knowledge-based semi-automated optimization caused a significantly larger number of high-dose hotspots but a similar D2% (52.54 vs.52.71 Gy,P=0.239).Conclusions The VMAT model can be used for the knowledge-based semi-automated optimization of IMRT plans to enhance the efficiency and OAR protection.However,the resulting high-dose hotspots need further manual intervention.
3.Absolute dose calibration and output factor simulation for flattened and flattening filter-free Monte Carlo model of 6 MV photon beams
Haizhen YUE ; Yibao ZHANG ; Qiaoqiao HU ; Zhuolun LIU ; Fan JIANG ; Jian GONG ; Hao WU
Chinese Journal of Radiological Medicine and Protection 2017;37(1):29-34
Objective To explore the Monte Carlo calculation methods for the absolute dose calibration and output factor of 6 MV flattening-filter ( FF) and flattening-filter free ( FFF) photon beams based on TrueBeam accelerator .Methods The BEAMnrc code was used to model the LINAC head of FF and FFF modes.The BEAM_up covers the components from the target to the monitor chamber , and BEAM_down includes the structures beneath the chamber , the dose deposit to the monitor chamber contributed by the incidence electrons and scattered particles from the secondary collimators were calculated respectively .The incidence electron-induced dose at certain depths on the central axis were simulated by means of the DOSXYZnrc code .By means of dose calibration equation , the calibration factor for the standard field (10 cm ×10 cm) and the output factors for various fields (1 cm ×1 cm-40 cm ×40 cm) were computed respectively .Results For the 6 MV FF and FFF beams under the standard 10 cm ×10 cm field, 1 MU equals to 7.747 ×1013 ±3.099 ×1011 and 3.248 ×1013 ±1.624 ×1011 electrons to the target , respectively , which deposited 21.53 and 35.01 cGy to the monitor chamber of the virtual accelerator respectively .The difference between the simulated and calculated output factors were 0.72%±1.4%and 0.56%±0.78%for FF and FFF , respectively .Conclusions The model generated and measured output factors agree well , indicating the good accuracy of the dose calculation by the model , which would provides basis for further clinical dosimetric studies .
4.Diagnosis and treatment for duodenal neuroendocrine tumors
Jianjun ZHAO ; Yang WANG ; Fan WU ; Peng LI ; Haizhen LU ; Dongbing ZHAO ; Jianqiang CAI
Chinese Journal of General Surgery 2014;29(3):192-194
Objective To evaluate the diagnosis and treatment of duodenal neuroendocrine tumors.Method We retrospectively analyzed data of 15 patients with duodenal neuroendocrine tumors admitted between August 1999 and July 2012.Result In all the 15 cases accurate and definitive diagnosis were achieved via pathological examination and immunohistochemistry.Clinical diagnostic methods included ultrasound,endoscopy,upper gastrointestinal imaging,abdominal CT,MRI,etc.7 cases underwent pancreaticoduodenectomy,2 cases were treated by local excision,4 cases by endoscopic excision,and total gastrectomy and distal gastrectomy was performed in one each case.Conclusions The diagnosis of duodenal neuroendocrine tumors is established mainly by endoscopy and diagnostic imaging.Surgical resection is the treatment of choice.Pancreatoduodenectomy and local excision is applicable for G2 and G3 patients while endoscopic excision can be used for G1 patients.
5.The performance of plastic scintillator detector in photon and electron beam
Meijiao WANG ; Kaining YAO ; Sha LI ; Haizhen YUE ; Zhuolun LIU ; Fan JIANG ; Hao WU ; Ruoxi WANG
Chinese Journal of Radiological Medicine and Protection 2021;41(3):205-211
Objective:To investigate the performance of W2 plastic scintillator in megavolt photon and electron beams.Methods:The photon and electron beam energy provided by linear accelerator was used to collect data of the W2 scintillator. The parameters include the electrometer reading stability, W2 dose and dose rate linearity, and angular response. And the dose uncertainty of the W2 correction factors was also investigated.Results:The standard deviation of the electrometer reading stability was between 0.03 and 0.47. The linear regression factors of W2 dose were all 1.0; the maximum deviation of the dose rates was 0.61%. The Cerenkov light radiation correction factor(CLR) for 6 and 10 MV were 0.741 and 0.746, respectively, and the CLR for 6, 9, 12 and 15 MeV were 0.750, 0.753, 0.757 and 0.757, respectively. The maximum deviation of dose uncertainty for 15 MeV was 3.15%.Conclusions:The signal obtained by the blue and green channel was no angular dependence, the same as the high-energy electron beam, which verified that the Cerenkov radiation correction factor has good linearity. W2 plastic scintillator can be applied to non-coplanar radiotherapy dosimetry.
6.Clinical and genetic characteristics of four children with Kabuki syndrome due to de novo variants of KMT2D gene
Haizhen FAN ; Yanmei WANG ; Yunhong WU ; Lifang JIA ; Lihong WANG ; Yansheng SHEN
Chinese Journal of Medical Genetics 2024;41(5):546-550
Objective:To explore the clinical and genetic characteristics of four children with Kabuki syndrome (KS) due to variants of KMT2D gene. Methods:Four children with KS diagnosed at the Children′s Hospital of Shanxi Province between January 2020 and December 2022 were selected as the study subjects. Whole exome sequencing was carried out for the children and their family members. Candidate variants were verified by Sanger sequencing and pathogenicity analysis.Results:The KS phenotype scores for the four children were 7, 8, 6, and 6, respectively. Child 2 also presented with a rare solitary kidney malformation. Genetic testing revealed that all children had harbored novel de novo variants of the KMT2D gene, including c. 16472_16473del, c. 858dup, c. 11899C>T, and c. 12844C>T, respectively. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), all of the variants were classified as pathogenic. Conclusion:For children showing phenotypes such as distinctive facial features, intellectual disability, developmental delay, cardiac abnormalities, and urinary system anomalies, KS should be considered. Early diagnosis and intervention can be achieved through genetic testing, especially in the presence of KMT2D gene mutations.
7.A comparative study of dosimetric verification of HalcyonTM treatment plans using Varian Portal Dosimetry and PTW array 1500
Qiaoqiao HU ; Fan JIANG ; Meijiao WANG ; Yibao ZHANG ; Kaining YAO ; Jian GONG ; Hao WU ; Haizhen YUE
Chinese Journal of Radiological Medicine and Protection 2019;39(1):58-62
Objective To compare two pretreatment plan QA methods for HalcyonTM accelerator using Portal Dosimetry (PD),and PTW OCTAVIUS 1500 detector array + Octagonal phantom (Oct 1500)respectively.Methods Parallel measurement-based pretreatment QA using two methods was performed for 22 IMRT/VMAT plans (74 fields) that have been used to treat 20 patients recruited in the Halcyon clinical trial.Several γ 2D comparisons were also applied to provide guidelines for Halcyon planning QA.Results Using Oct1500 method,the γ 2D passing rates for 74 fields in 22 Plans were 95.26±3.59,95.01±3.62 (Local Dose),99.05± 1.35,98.57± 1.96 (Max Dose) respectively.Two-related samples non-parametric tests suggested that the differences between the evaluation criteria were of statistical significance (Z =-7.220,-4.108,P<0.05).For PD method,the γ 2D passing rates were 84.11% ± 1.35% (1 mm/1%),99.07%± 1.35% (2 mm/2%),and 99.86% ± 1.35% (3 mm/3%).Two-related samples non-parametric tests suggested that the differences between evaluation criteria of PD method were statistically significant (Z =-7.475,-7.475,-6.906,P<0.05).For 74 fields and max dose,3 mm/3% evaluation criteria,two-related samples non-parametric tests suggested that the differences between PD and Oct1500 method were statistically significant (Z=-5.072,P<0.05).Conclusions Both methods can be used for Halcyon pretreatment plan QA.PD is superior to Oct1500 with respect to efficiency and spatial resolution-induced verification accuracy.The criteria of 2 mm/2% for PD,and Max Dose/3 mm/3% for Oct1500 was suggested.
8.Effects of brusatol on the malignant biological behavior of ovarian cancer cells by regulating SPHK1/S1P/S1PR3 signaling pathway
Mingyan ZHONG ; Fan YANG ; Haizhen LI ; Qi ZHAN ; Wei ZHANG
China Pharmacy 2024;35(16):1991-1997
OBJECTIVE To investigate the effects of brusatol on the malignant biological behavior of ovarian cancer cells by regulating the sphingosine kinase 1 (SPHK1)/sphingosine-1-phosphate (S1P)/sphingosine-1-phosphate receptor 3 (S1PR3) signaling pathway. METHODS Human ovarian cancer cell strain SKOV-3 were randomly divided into control group, brusatol group, SPHK1 overexpression group, brusatol+blank load group, brusatol+SPHK1 overexpression group. The cell viability, colony formation rate, the number of migration and invasion, apoptosis rate, the expressions of cell proliferation-related proteins [myelocytomatosis viral oncogene homolog (C-myc)], apoptosis-related proteins [B-cell lymphoma-2 (Bcl-2), Bcl-2 associated X protein (Bax)], epithelial mesenchymal transition (EMT)-related proteins (E-cadherin, N-cadherin) and SPHK1, S1P, S1PR3 proteins were all detected in each group. Transplanted tumor model of nude mice was constructed by using SKOV-3 cells and randomly separated into control group, brusatol low-dose, medium-dose and high-dose groups, SPHK1 overexpression group, high- dose brusatol+blank load group, and high-dose brusatol+SPHK1 overexpression group; the growth of transplanted tumors were detected. The nude mice model of SKOV-3 transplantation tumor was randomly divided into control group, brusatol group, SPHK1 overexpression group, brusatol+blank load group, and brusatol+SPHK1 overexpression group; the proliferation and apoptosis of transplanted tumor tissue, the expressions of EMT-related Δ 基金项目江西省中医药管理局科技计划项目(No.2023B0762) *第一作者 副主任药师 。研究方向 :药学研究及药理学 。E- proteins and SPHK1/S1P/S1PR3 signaling pathway proteins mail:jsgj2023@126.com were detected in each group. RESULTS Cell experiments in # 通信作者 主任医师,硕士。研究方向:妇科及妇科肿瘤学。E- vitro had shown that compared with the control group, the cell mail:11638199@qq.com viability, clone formation rate, migration number, invasion 中国药房 2024年第35卷第16期 China Pharmacy 2024 Vol. 35 No. 16 · 1991 · number, protein expressions of C-myc, Bcl-2, N-cadherin, SPHK1, S1P and S1PR3 were decreased significantly in brusatol group (P<0.05), while the apoptosis rate, protein expressions of Bax and E-cadherin were increased significantly (P<0.05); overexpression of SPHK1 could weaken the effects of brusatol on the above indicators in SKOV-3 cells. Mice experiments in vivo had shown that compared with the control group, the transplanted tumor volumes of nude mice in the brusatol low-dose, medium- dose and high-dose groups were decreased significantly in a dose-dependent manner after 21 days of intervention (P<0.05). Brusatol of high dose could also significantly reduce the protein expressions of C-myc, Bcl-2, N-cadherin, SPHK1, S1P and S1PR3 in transplanted tumor tissue of nude mice (P<0.05), and significantly increase the protein expressions of Bax and E- cadherin (P<0.05); overexpression of SPHK1 could weaken the effects of brusatol on the above indicators in transplanted tumor tissue of nude mice. CONCLUSIONS Brusatol can inhibit the proliferation, cloning, EMT, migration and invasion of ovarian cancer cells, and induce their apoptosis by down-regulating the expression of SPHK1/S1P/S1PR3 signaling pathway. It can also inhibit the growth of ovarian cancer cells in nude mice, ultimately suppressing their malignant biological behavior and exerting significant anti-cancer effects on ovarian cancer.