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Objective:To investigate the clinical effect of stereotactic radiation therapy combined with sorafenib in the treatment of primary hepatic cancer (PHC).Methods:Ninety-two PHC patients admitted to Cancer Hospital of China Medical University from January 2017 to May 2018 were selected and divided into the observation group and the control group according to the random number table method, with 46 cases in each group. The control group was treated with stereotactic radiation therapy, and the observation group was treated with sorafenib on the basis of the control group. Clinical efficacy and incidence of adverse reactions in the two groups were compared; the scores of Karnofsky performance scale (KPS) and the levels of serum vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), hypoxia-inducing factor (HIF-1α), soluble interleukin-2 receptor (sIL-2R), transforming growth factor (TGF-β1) and alpha-fetoprotein (AFP) before and after the treatment between the two groups were compared. The overall survival (OS) of patients in both groups was recorded after 36 months of follow-up.Results:The total effective rate in the observation group was higher than that in the control group: 84.78%(39/46) vs. 65.22%(30/46), there was statistical difference ( χ2 = 4.70, P<0.05). After the treatment, the score of KPS in the observation group was higher than that in the control group: (85.06 ± 7.19) scores vs. (71.16 ± 7.08) scores; the levels of VEGF, bFGF, HIF-1α, AFP, TGF-β1, sIL-2R in the observation group were lower than those in the control group: (189.52 ± 31.47) ng/L vs. (235.81 ± 35.45) ng/L, (3.89 ± 0.97) ng/L vs. (6.74 ± 1.85) ng/L, (50.17 ± 6.09) ng/L vs. (53.07 ± 6.28) ng/L, (85.76 ± 14.09) μg/L vs. (131.51 ± 18.74) μg/L, (81.07 ± 12.96) μg/L vs. (106.58 ± 15.07) μg/L, (311.58 ± 74.81) kU/L vs. (405.97 ± 85.74) kU/L, there were statistical differences ( P<0.05). The results of 36 months follow-up showed that the 1-year and 3-year OS in the observation group were higher than those in the control group: 69.57% (32/46) vs. 58.70% (27/46), 43.47% (20/46) vs. 28.26 %(13/46), there were significant differences ( χ2 = 4.78, 3.94, P<0.05). Conclusions:Stereotactic radiation therapy combined with sorafenib can effectively improve the efficacy of PHC patients, reduce the expression of VEGF and bFGF, effectively inhibit tumor growth, but also prolong the survival time of patients, with both safety and high effectiveness, and good use value.
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OBJECTIVE@#To propose an deep learning-based algorithm for automatic prediction of dose distribution in radiotherapy planning for head and neck cancer.@*METHODS@#We propose a novel beam dose decomposition learning (BDDL) method designed on a cascade network. The delivery matter of beam through the planning target volume (PTV) was fitted with the pre-defined beam angles, which served as an input to the convolution neural network (CNN). The output of the network was decomposed into multiple sub-fractions of dose distribution along the beam directions to carry out a complex task by performing multiple simpler sub-tasks, thus allowing the model more focused on extracting the local features. The subfractions of dose distribution map were merged into a distribution map using the proposed multi-voting mechanism. We also introduced dose distribution features of the regions-of-interest (ROIs) and boundary map as the loss function during the training phase to serve as constraining factors of the network when extracting features of the ROIs and areas of dose boundary. Public datasets of radiotherapy planning for head and neck cancer were used for obtaining the accuracy of dose distribution of the BDDL method and for implementing the ablation study of the proposed method.@*RESULTS@#The BDDL method achieved a Dose score of 2.166 and a DVH score of 1.178 (P < 0.05), demonstrating its superior prediction accuracy to that of current state-ofthe-art (SOTA) methods. Compared with the C3D method, which was in the first place in OpenKBP-2020 Challenge, the BDDL method improved the Dose score and DVH score by 26.3% and 30%, respectively. The results of the ablation study also demonstrated the effectiveness of each key component of the BDDL method.@*CONCLUSION@#The BDDL method utilizes the prior knowledge of the delivery matter of beam and dose distribution in the ROIs to establish a dose prediction model. Compared with the existing methods, the proposed method is interpretable and reliable and can be potentially applied in clinical radiotherapy.
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Humans , Deep Learning , Head and Neck Neoplasms/radiotherapy , Algorithms , Neural Networks, ComputerABSTRACT
Objective:To explore the efficacy of elective nodal irradiation (ENI) and involved field irradiation (IFI) combined with chemotherapy in treatment of esophageal cancer.Methods:A total of 104 patients with esophageal cancer in Affiliated Hospital of Jiangnan University from May 2018 to May 2020 were selected as subjects for prospective study. All patients were randomly divided into observation group and control group by lottery method with 52 cases in each group. The target volume of observation group was delineated with IFI, and the control group was delineated with ENI. The curative effects, the levels of serum tumor markers [carbohydrate antigen 50 (CA50), squamous cell carcinoma (SCC) and carcinoembryonic antigen (CEA)] before and after treatment, the 1-year overall survival (OS) rate, the incidence of adverse reactions and the scores of various dimensions of health survey summary (SF-36) after treatment were compared between the two groups.Results:The total effective rate in the observation group was 90.38% (47/52), the total effective rate in the control group was 84.62% (44/52), and the difference was not statistically significant ( χ2 = 0.79, P =0.374). There was no statistical difference in CA50, CEA, SCC levels between the two groups before and after treatment (all P > 0.05). After treatment, the CA50, CEA and SCC levels in the two groups were lower than those before treatment, and the differences were statistically significant (all P < 0.05). The 1-year OS rate of the observation group was 94.23%, the control group was 90.38%, and the difference in OS between the two groups was not statistically significant ( χ2 = 0.54, P = 0.462). The incidence of acute radiation esophagitis in the observation group was lower than that in the control group, and the difference was statistically significant ( P < 0.001). There was no statistical difference between the two groups in SF-36 scale scores of physical functioning, role-physical, bodily pain, mental health, vitality, social functioning, role-emotional, and general health after treatment (all P > 0.05). Conclusions:Both ENI and IFI are effective treatments for patients with esophageal cancer. There is no significant difference in the quality of life of patients between the two delineation methods, but the incidence of acute radiation esophagitis is lower in patients with IFI regimen.
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Objective:To investigate the efficacy and safety of camrelizumab combined with stereotactic body radiation therapy (SBRT) in the treatment of advanced oligometastaticnon-small cell lung cancer (NSCLC).Methods:Eighty-six patients with advanced oligometastatic NSCLC who met the inclusion and exclusion criteria from March 2020 to August 2021 in the Second People′s Hospital of Yibin were divided into the control group (43 cases) and the treatment group (43 cases) according to the random number table method, the control group was given camrelizumab combined with conventional radiotherapy, and the treatment group was given camrelizumab combined with SBRT. After 8 weeks of treatment, the efficacy of the two groups was evaluated, the occurrence of side effects in the two groups was counted, the serum tumor markers [carcinoembryonic antigen (CEA), squamous cell carcinoma antigen (SCC-Ag), cytokeratin 19 fragment anti-21-1 (CYFRA21-1)] levels were detected.Results:The objective effective rate of the treatment group was significantly higher than that of the control group:: 72.09% (31/43) vs. 51.16%(22/43), the difference was statistically significant ( P<0.05); the incidence of radiation pneumonia in the treatment group was significantly lower than that in the control group: 4.65% (2/43) vs. 18.60% (8/43), the difference was statistically significant ( P<0.05), and there was no significant difference in the incidences of other side effects such as cutaneous capillary endothelial proliferation (CCEP), liver damage, hypothyroidism, and radiation esophagitisbetween the treatment group and the control group ( P>0.05); the levels of serum CEA, SCC-Ag, CYFRA21-1after treatmentin the two groups were significantly lower than those before treatment, treatment group: treatmentgroup: (8.81 ± 4.82) ng/L vs. (81.67 ± 50.88) ng/L, (1.13 ± 0.55) ng/L vs. (1.56 ± 1.03) ng/L and (2.92 ± 0.99) ng/L vs. (4.63 ± 1.39) ng/L, controlgroup: (30.49 ± 19.44) ng/L vs. (89.91 ± 50.10) ng/L, (1.56 ± 1.23) ng/L vs. (1.86 ± 1.33) ng/L and (4.01 ± 2.10) ng/L vs. (5.03 ± 3.44) ng/L. and the levels after treatment in the treatment group were significantly lower than those in the control group, and there were statistical differences ( P<0.05). Conclusions:Camrelizumab combined with SBRT treatment for patients with advanced oligometastatic NSCLC can effectively reduce the levels of serum CEA, SCC-Ag, CYFRA21-1, and significantly improve the short-term efficacy, with relatively low incidence of toxic side effects.
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Objective:Utilizing multi-criterion optimization (MCO) technology to improve plan design quality based on knowledge-based planning (KBP) model.Methods:Fifty-five patients with nasopharyngeal carcinoma (NPC) who had completed radiotherapy were selected, and fixed-field intensity-modulated radiotherapy (IMRT) technology was used in each case. Among them, 40 cases were randomly selected as training set 1. Then, IMRT plans in training set 1 were preprocessed by MCO technology to construct a new training set 2. With the initial training set 1 and the processed training set 2 as training samples, the traditional KBP model and the MCO-KBP model refined by MCO technology were trained, respectively. Among the remaining 15 cases, 5 cases were randomly selected as the validation set, and the remaining 10 cases were used as the test set. After verification, the test set was used to statistically analyze the plan quality of the initial manual plan and the automatic plan generated by the traditional KBP model and the MCO-KBP model.Results:The target dose (D 95%) of plans generated by the traditional KBP model and the MCO-KBP model met the clinical requirements. Conformity index (CI) and homogeneity index (HI) were almost the same ( P>0.05), and the doses of organ at risk (OAR) of the automatic plans generated by the MCO-KBP model were lower than those of the traditional KBP model. For example, compared with the traditional KBP model, the average D max of the brainstem in the automatic plans generated by the MCO-KBP model was lower by 2.13 Gy, the average D mean of the left parotid gland was lower by 1.39 Gy, the average D mean of the right parotid gland was lower by 1.59 Gy, and the average D max of the left optic nerve was lower by 1.42 Gy, the average D max of the right optic nerve was lower by 1.16 Gy, and the average D max of the pituitary gland was lower by 1.88 Gy. All of the above-mentioned dosimetry indexes were statistically significant. Conclusion:Compared with the traditional KBP model, the IMRT plans designed by the refined MCO-KBP model have obvious advantages in the protection of OAR, which proves the feasibility of utilizing MCO technology to improve the plan design quality of the KBP model.
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Objective:To realize the interactive form evaluation of radiotherapy dose and the automatic calculation of conformity index (CI) and heterogeneity index (HI) in the Eclipse planning system.Methods:The Eclipse Scripting API application development interface and C# programming language were employed to develop it with script plug-ins combined with independent programs. The visual interface programming and call the relevant dose query function in the API were utilized to realize the interactive table dose evaluation and the automatic calculation of HI. The functions of calling dosage structure creation and structure Boolean operation in the API were adopted to realize the automatic calculation of CI.Results:15 clinical radiotherapy cases of nasopharyngeal carcinoma were selected. The dose evaluation results were statistically compared between this method and the module equipped in the Eclipse system. The results showed that the accuracy was consistent between these two methods ( P>0.05), whereas the evaluation efficiency of this method was significantly higher compared with that of the Eclipse system module ( P<0.05). Conclusions:The interactive evaluation form in this article has a friendly interface, which allows users to more conveniently perform dose assessment, multi-plan comparison, and calculation of CI and HI, which effectively improves work efficiency and can better serve the clinical and scientific research work of radiotherapy.
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Objective:To develope a self-adjustable automatic planning method of intensity modulated radiotherapy based on predicted dose, in order to enhance the robustness of automatic planning.Methods:After the patients′ dose by 3D U-Res-Net_B network was predicted, the current dose was calculated based on the last iteration result, then the predicted dose was combined to calculate the target dose and optimized. With all iterations completed or exit conditions satisfied, final treatment plannings would be acquired. A total of 30 cases of rectal cancer were tested to verify the effectiveness of the algorithm.Results:The mean value of planning target volumes′ V100% was (95.03±0.91)% for clinical plans, close to (94.67±1.96)% for automatical plans( P>0.05), and better than (92.90±2.13)% for predicted dose with the statisically significant difference ( t=29.0, P<0.05). Automatic planning′s indexes such as V35 of small intestines, V40 of bladders and V20 - V40 of femoral heads were lower than predicted and clinical ones, with the statisically significant difference( t=4.5-118.0, P<0.05). Discrepancy in other indexes of organs at risk was not statistically significantly different( P>0.05). Conclusions:This method made automatic planning processes more robust and more adaptive to difficult clinical situations.
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Objective To train individualized three-dimensional (3D) dose prediction models for radiotherapy planning,and use the models to establish a planning quality control method.Methods A total of 99 cases diagnosed as early nasopharyngeal carcinoma (NPC) were analyzed retrospectively,who received simultaneous integrated boost (SIB) with volumetric modulated arc therapy (VMAT).Seven geometric features were extracted,including the minimum distance features from each organs at risk (OARs) to planning target volume (PTV),boost targets and outline,as well as four coordinate position characteristics.89 cases were trained and 10 cases were tested based on 3D dose distribution prediction models using artificial neural network (ANN).A planning quality control method were established based on the prediction models.The dosimetric parameters including D2％,D25％,D50％,D75％ and mean dose (MD) of each OAR were used as quality control indicators,and the passing criteria was defined as that the dosimetric difference between manual planning and the predicted dose should be less than 10％.The quality control method was tested with 10 plans ()esigned by a junior physicist.Results There was no significant discrepancy between the model predicted dose and the result of expert plan in the main dosimetric indexes of 18 OARs.The dose differences of D2％,D25％,D50％,D75％ and MD were all controlled within 1.2 Gy.All the 10 plans designed by a junior physicist reached the general clinical dose requirements,while by using our proposes quality control method,one of these plans was observed not optimal enough and some dosimetric parameters of spinal cord,spinal cord PRV,brainstem and brainstem PRV could be improved.After re-optimizing this plan according to the predicted values of the model,the D2％ of spinal cord and brainstem decreased by 8.4 Gy and 5.8 Gy,respectively.Conclusions This study proposes a simple and convenient quality control method for radiotherapy planning.This method could overcome the disadvantage of unified dose constrains without considering patient-specific conditions,and improve the quality and stability of individualized radiotherapy planning.
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Objective@#To train individualized three-dimensional (3D) dose prediction models for radiotherapy planning, and use the models to establish a planning quality control method .@*Methods@#A total of 99 cases diagnosed as early nasopharyngeal carcinoma (NPC) were analyzed retrospectively, who received simultaneous integrated boost (SIB) with volumetric modulated arc therapy (VMAT). Seven geometric features were extracted, including the minimum distance features from each organs at risk (OARs) to planning target volume (PTV), boost targets and outline, as well as four coordinate position characteristics.89 cases were trained and 10 cases were tested based on 3D dose distribution prediction models using artificial neural network (ANN). A planning quality control method were established based on the prediction models. The dosimetric parameters including D2%, D25%, D50%, D75% and mean dose (MD) of each OAR were used as quality control indicators, and the passing criteria was defined as that the dosimetric difference between manual planning and the predicted dose should be less than 10%. The quality control method was tested with 10 plans designed by a junior physicist.@*Results@#There was no significant discrepancy between the model predicted dose and the result of expert plan in the main dosimetric indexes of 18 OARs. The dose differences of D2%, D25%, D50%, D75% and MD were all controlled within 1.2 Gy.All the 10 plans designed by a junior physicist reached the general clinical dose requirements, while by using our proposes quality control method, one of these plans was observed not optimal enough and some dosimetric parameters of spinal cord, spinal cord PRV, brainstem and brainstem PRV could be improved. After re-optimizing this plan according to the predicted values of the model, the D2% of spinal cord and brainstem decreased by 8.4 Gy and 5.8 Gy, respectively.@*Conclusions@#This study proposes a simple and convenient quality control method for radiotherapy planning. This method could overcome the disadvantage of unified dose constrains without considering patient-specific conditions, and improve the quality and stability of individualized radiotherapy planning.
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PURPOSE: The aim is to study the dependence of deformable based auto-segmentation of head and neck organs-at-risks (OAR) on anatomy matching for a single atlas based system and generate an acceptable set of contours. METHODS: A sample of ten patients in neutral neck position and three atlas sets consisting of ten patients each in different head and neck positions were utilized to generate three scenarios representing poor, average and perfect anatomy matching respectively and auto-segmentation was carried out for each scenario. Brainstem, larynx, mandible, cervical oesophagus, oral cavity, pharyngeal muscles, parotids, spinal cord, and trachea were the structures selected for the study. Automatic and oncologist reference contours were compared using the dice similarity index (DSI), Hausdroff distance and variation in the centre of mass (COM). RESULTS: The mean DSI scores for brainstem was good irrespective of the anatomy matching scenarios. The scores for mandible, oral cavity, larynx, parotids, spinal cord, and trachea were unacceptable with poor matching but improved with enhanced bony matching whereas cervical oesophagus and pharyngeal muscles had less than acceptable scores for even perfect matching scenario. HD value and variation in COM decreased with better matching for all the structures. CONCLUSION: Improved anatomy matching resulted in better segmentation. At least a similar setup can help generate an acceptable set of automatic contours in systems employing single atlas method. Automatic contours from average matching scenario were acceptable for most structures. Importance should be given to head and neck position during atlas generation for a single atlas based system.
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Humans , Brain Stem , Head and Neck Neoplasms , Head , Larynx , Mandible , Methods , Mouth , Neck , Organs at Risk , Pharyngeal Muscles , Radiotherapy , Spinal Cord , TracheaABSTRACT
18F-FDG PET-CT is recommended for the diagnosis and treatment of non-small cell lung cancer (NSCLC), and guiding the optimization of radiotherapy planning. The target area determined by biological information carried by functional images is defined as biological target volume (BTV). However, BTV significantly differs from the gross tumor volume (GTV) and internal target volume (ITV) defined by the International Commission on Radiation Units and Measurements (ICRU) report. It is still a challenging task to directly apply BTV to radiotherapy planning. The limitation of PET image, the accuracy of fusion with auxiliary anatomic images and the influence of respiratory movement cause the uncertainty of BTV definition in NSCLC patients. Referring to different anatomical images, multiple approaches can be employed to achieve BTV motion information compensation. Application of PET-CT in predicting the prognosis of NSCLC patients after radiotherapy and distinguishing the recurrence risk of biological sub-target contribute to achieving the dose planning for radiotherapy planning.
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Objective To make a cost-effectiveness analysis for stereotactic radiotherapy and intensity-modulated radiotherapy using linear accelerators against malignant tumors, then to provide references for choosing a more cost-effective radiotherapy for the patient. Methods Basic information of patients subject to radiotherapy(gender, age, date of admission, days of hospital stay), hospitalization cost, admission diagnosis, clinical outcomes among others of 320 patients with malignant tumors(lung tumor, head and neck tumor, bone metastases, liver tumor) were collected from Hubei, Guangxi and Fujian provinces. The cost of hospitalized radiotherapy and treatment effect of these patients were compared to identify the more cost effective of the two methods. Results The effective rates of stereotactic radiotherapy and intensity-modulated radiotherapy were 99.1% (108/109) and 97.2% (205/211) respectively, and the difference was not significant( P>0.05). The average hospitalization cost of treatment of the two groups was 37 545.56 yuan and 48 159.05 yuan respectively; the cost-effectiveness ratio was 37 886.54 and 49 546.35 respectively. Conclusions The short-term effects of stereotactic and intensity-modulated radiotherapy are similar, but the cost of intensity-modulated radiotherapy is higher. The minimum cost analysis shows that stereotactic radiotherapy is more cost effective.
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Objective To compare target dosimetric distribution and normal tissue radiation between different static intensity-modulated radiation therapy (IMRT)plans and volumetric modulated arc therapy (VMAT),and to identify the best IMRT plan for lymphoma patients needed mediastinal radiation. Methods A total of 11 patients with lymphoma who received first course radiotherapy in the mediastinal region after che-motherapy in Cancer Hospital & Shenzhen Hospital,Chinese Academy of Medical Sciences and Peking Union Medical College from March 2017 to January 2019 were included in the study. There were 8 males and 3 fe-males,2 patients were in Ann Arbor stage Ⅰ-Ⅱ,and 9 cases in Ⅲ-Ⅳ stage. There were 6 patients with Hodgkin lymphoma (HL)and 5 patients with non-Hodgkin lymphoma (NHL). Patients with HL and NHL were given prescript doses of 36 Gy and 50 Gy,respectively. Three plans were designed for each patient:static 5F-IMRT,7F-IMRT and VMAT plan. The target dosimetric distribution,normal tissue radiation dose,and effi-ciency of each plan were evaluated. Results The mean conformity index (CI)and homogeneity index (HI) values of plan target volume (PTV)in 5F-IMRT,7F-IMRT,VMAT plan were 0. 64 ± 0. 06,0. 67 ± 0. 05, 0. 76 ± 0. 04 (F = 17. 045,P < 0. 001)and 1. 07 ± 0. 01,1. 07 ± 0. 01,1. 09 ± 0. 01 (F = 9. 258,P =0. 001),respectively. VMAT showed significantly better CI than two static IMRT plans (both P < 0. 001),but worse HI (both P < 0. 001). The lungs low dose irradiation volume (V (V 5 )and high dose irradiation volume 30 )in 5F-IMRT,7F-IMRT,VMAT plan were (43. 98 ± 7. 77)％,(42. 71 ± 4. 98)％,(55. 92 ± 8. 16)％(F = 8. 281,P = 0. 001)and (8. 19 ± 2. 97)％,(8. 25 ± 2. 87)％,(7. 53 ± 3. 16)％ (F = 0. 140,P =0. 870),respectively. The volume of low dose irradiation in lungs of VMAT plan was significantly higher than 5F-IMRT and 7F-IMRT plans (both P < 0. 001),while high dose volume was no significant difference. The left and right breast low dose irradiation volume (V 4 )in 5F-IMRT,7F-IMRT and VMAT plan were (24. 29 ± 8. 14)％,(23. 87 ± 7. 70)％,(80. 17 ± 22. 92)％ (F = 14. 505,P = 0. 005)and (22. 12 ± 13. 28)％, (21. 13 ± 13. 01)％,(81. 77 ± 20. 76)％ (F = 13. 938,P = 0. 006),respectively. VMAT showed signifi-cantly higher breast low dose irradiation volume than static IMRT plan (both P < 0. 05). The number of monitor units and treatment time in 5F-IMRT,7F-IMRT,VMAT plan were (1622 ± 281)MU,(1729 ± 286)MU, (411 ± 75)MU (F = 105. 277,P < 0. 001)and (6. 79 ± 0. 93)min,(7. 42 ± 0. 95)min,(4. 98 ± 0. 00)min (F = 29. 545,P < 0. 001),respectively. VMAT showed significantly less monitor units than static IMRT (both P < 0. 001)and shorter treatment time (both P < 0. 001). Conclusion For lymphoma patients who have the indication of mediastinal radiotherapy,VMAT is highly efficient and has no definite dose advan-tage,the static 5F-IMRT or 7F-IMRT plan has good conformal and uniform target area,and some organs at risk exposure is even lower.
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Objective To explore the clinical effect of concurrent radiotherapy and chemotherapy in the treatment of advanced cervical cancer.Methods From January 2010 to January 2011,sixty patients with cervical cancer in Taizhou Cancer Hospital were randomly divided into two groups ,with 30 cases in each group.The control group was given radiotherapy alone ,the observation group was given concurrent radiotherapy and chemotherapy .The adverse reaction,curative effect,long -term effect of 5 -year follow -up were compared between the two groups. Results The total effective rate of the observation group was 93.33%,which was significantly higher than 73.33%of the control group,the difference was statistically significant (χ2＝14.397,P＜0.05).The 5-year survival rate of the observation group was 76.67%,which was significantly higher than 53.33% of the control group,the difference was statistically significant ( χ2＝11.922,P ＜0.05).The local recurrence rate and distant metastasis rate of the observation group were 16.67%,13.33%,respectively,which were significantly lower than those of the control group , the differences were statistically significant (χ2＝7.401,5.115,all P＜0.05).The incidence rate of adverse reaction of the control group was 13.33%,which of in the observation group was 23.33%,the difference was not statistically significant(χ2＝3.340,P ＞0.05).Conclusion The efficacy of concurrent radiotherapy and chemotherapy for patients with advanced cervical cancer is better ,and the survival rate of patients with advanced cervical cancer is better.
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Objective To investigate the safety and efficacy of re-irradiation with stereotactic body radiotherapy(SBRT) for treating locally recurrent advanced pancreatic cancer.Methods From 2014 to 2017,7 patients with stage Ⅲ pancreatic cancer were treated by re-irradiated with SBRT at Shanghai Changhai Hospital.SBRT was delivered via the G4 type cyberknife robotic stereotactic radiosurgery system in all the patients.The median dose of the first SBRT was 35Gy/5-7 fx,and the median dose of re-irradiation with SBRT was 31 Gy/5-8 fx.6 patients had undergone sequential chemotherapy either with gemcitabine or S-1 based therapy except one patient who refused the chemotherapy.Results There were 5 male and 2 female patients.The median overall survival (OS) of 7 patients was 30 months.Patients were re-irradiated with SBRT after a median interval of 10 months after the first SBRT.Median OS and locally relapse-free survival (LFRS) from re-irradiation were 13 months and 11 months,respectively.Three months after re-irradiation,3(42.9％) patients had partial remission and 4 patients had stable disease.Pain disappeared in 4 patients at the end of reirradiation and significant pain was alleviated in 2 patients 1 month after re-irradiation.There were no toxicities of grade 3 or higher grade during two courses of SBRT.Conclusions For patient with locally recurrent advanced pancreatic cancer,SBRT re irradiation regimen was associated with acceptable toxicity,which can effectively alleviate the pain,prolong the survival and improve the life quality.
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Objective To assess the cumulative doses and side effects after two courses of stereotactic body radiation therapy (SBRT) for pancreatic cancer. Methods Twenty-four pancreatic cancer patients who received two courses of SBRT were enrolled. Organ endangering dose accumulations were calculated by rigid and non-rigid registration. All doses were recalculated to an equivalent dose of 2 Gy per fraction. Results The median of accumulated maximal dosage (Dmax) and dosage per 1cc(D1cc) of the stomach,duodenum and the bowel were 43.87 and 35.28 Gy 3,35.53 and 26.59 Gy3,45.08 and 36.18 Gy3; and the median volume under the dosage of 10Gy (V10) was 107.40,23.98 and 169.26cc, respectively. The median accumulated Dmaxand the dosage of 35% volume(D0.35) of the spinal cord was 8.42 and 7.83Gy3. The median cumulative Dmeanand D2/3of the left and right kidney were 5.18 and 3.65 Gy3, 3.50 and 2.57 Gy3, respectively. The median cumulative Dmeanand D50%of the liver was 5.18 and 3.64Gy3,respectively. The median summed dose to the overlapping radiation field of the two courses was 93.38 Gy3. No grade 3-4 toxicity occurred. Conclusions The cumulative doses to organs at risk as dose constraints were safe and acceptable,which could be used as a reference to evaluate whether a second SBRT could be done after initial SBRT for pancreatic cancer.
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Objective To propose the method of dose distribution calculated by one-step optimization with 7 shells (Cao method) and compare with that by three-step optimization with 4 shells (Blanck method) and CyberKnife treatment plans for pancreatic cancer. Methods 20 cases of pancreatic cancer who underwent CyberKnife treatment were retrospectively analyzed,and CT was performed to localize and delineate the target area and endangering organs. Dosage was optimized and evaluated with Blanck method and Cao method. The planning target volume (PTV) conformity index (CI), new conformity index (nCI), homogeneity index (HI),gradient index (GI), coverage, dose-volume and doses to organs at risk were compared. Results Compared with Blanck method, CI (1.11 ± 0.05 vs 1.15 ± 0.05), nCI (1.20 ± 0.06 vs 1.23 ± 0.06), coverage [(92.48 ± 1.85)% vs (93.53 ± 2.15)%], volumes encompassed by 100% and 30% prescription dose line (36.46 ± 16.64 vs 38.19 ± 17.68; 286.19 ± 126.52 vs 320.93 ± 154.82) and monitor unit (56 369 ± 20 019 vs 57 814 ± 20 531) were significantly decreased,while GI was increased (3.22 ± 0.19 vs 3.11 ± 0.19), and all the differences were statistically significant (P<0.05). Additionally, Dmax of the intestine (21.17 ± 2.90 vs 20.63 ± 3.13), D10cc of the stomach (12.78 ± 2.57 vs 13.11 ± 2.43), D5ccof the duodenum (11.01 ± 3.45 vs 11.50 ± 3.25), D10ccof the duodenum (9.30 ± 3.31 vs 9.78 ± 3.07) and D0.35ccof the spinal cord (6.09 ± 0.98 vs 6.59 ± 0.92) were all significantly decreased (P<0.05). No significant differences were found on other parameters. Conclusions Better dose distributions are accessible by one-step optimization with 7 shells in CyberKnife treatment plans for pancreatic cancer.
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Objective To study the patient movements features during radiotherapy . Methods Randomly selected 120 patients treated in our hospital from February to July on 2016,including 60 thorax treatment and 60 abdomen treatment. The movement data of patient treatment location during radiotherapy treatment was real time monitored by using Sentinel system,movement features of patient′s location during radiotherapy was analyzed. Paired t-test difference. Results During radiotherapy,patient′s treatment location movement types and proportion were motionless type 14. 0%,Moving stable type 64. 0%,Jumping type 8. 7%,increasing type 13. 3%.Patients with thoracic and abdominal radiotherapy,the maximum deviation of IMRT and VMAT treatment were (6.55±2. 34) mm and (4.97±1. 24) mm (P = 0. 002),(3.97±1. 80) mm and (2.69± 1. 42) mm (P = 0. 004).In single treatment,the deviation value of the patient′s treatment location increased gradually with the treatment time increasing and the deviant of thoracic is greater than abdominal at the same time after the treatment beginning. Conclusions Patient′s treatment location movement during radiotherapy is commonly exist,using the technology of VMAT treatment can effectively reduce the treatment site movement of the patient during the treatment and ensure the accuracy of dose.
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Objective To analyze the setup errors by cone-beam computed tomography (CBCT) for breast cancer patients who were immobilized with neck and breast thermoplastic mask and received intensity modulated radiation therapy (IMRT), and to calculate the external margins from the clinical target volume (CTV) to the planning target volume (PTV) (MPTV) of tumors. Methods Twenty-five breast cancer patients who were immobilized with neck and breast thermoplastic mask and received IMRT in the Oncology Department of Tongji Hospital Affiliated to Tongji Medical College of Huazhong University of Science and Technology from November 2016 to June 2017 were enrolled. The position of the patients were verified by CBCT before treatment . The linear and rotation errors of the X, Y and Z axes were analyzed by online bone registration. The systematic errors (Σ) and random errors (σ) of the patients were also calculated, and then the margins from CTV to PTV margins were calculated based on MPTV=2.5Σ+0.7σ. 25 patients'height, weight, body mass index (BMI) and the maximum diameters of CTV in the lateral, longitudinal and vertical directions were recorded, and the relation between the setup errors and the above mentioned was analyzed by using Spearman method. Results A total of 174 CBCT scans for 25 breast cancer patients were completed. The group Σ were 1.40 mm, 1.50 mm and 1.20 mm, and rotation errors were 0.9°, 0.7° and 0.8° at the X, Y and Z axes, respectively. The group σ were 2.20 mm, 3.00 mm and 1.40 mm, and rotation errors were 0.7°, 0.6° and 0.7° at the X, Y and Z axes, respectively. MPTVwas recommended as 4.90 mm, 6.00 mm and 3.90 mm at the X, Y and Z axes, respectively. There was no correlation between the height, weight, BMI of the patients and the setup errors (all P ＞ 0.05). However, there was a significant correlation between the maximum lateral, longitudinal diameters of the CTV and the setup errors (rs= 0.406, P= 0.044; rs= 0.512, P= 0.009). Conclusions The neck and breast thermoplastic mask can improve the diagnostic accuracy of radiotherapy in breast cancer patients. The data of setup errors verified by CBCT can provide meaningful references for the setting of MPTV.
ABSTRACT
Objective To compare the application values and setup errors between vacuum bag plus body mask and customized alpha cradle duringproton and carbon therapy using Siemens 6D robotic couch in prostate cancer patients.Methods Nineteen patients received vacuum bag plus body mask setup were allocated into the vacuum bag group andl9 patients with alpha cradle were assigned into the alpha cradle group.Orthogonal X-ray portals were performed to verify the treatment position before beam delivery in every fraction.The couch correction between the portal and reference DRR through manual image registration was recorded as setup errors in 6 directions including the lateral,supine-inferior,anterior-posterior,yaws,roll and pitch,respectively.Two-tail t-test was used to analyze the setup error data from each direction between two groups.Results In total,452 and 436 sets of data errors were collected from the vacuum bag and alpha cradle groups.The average setup errors and standard deviation in the vacuum bag and alpha cradle groups in the lateral,supine-inferior,anterior-posterior,yaws,roll and pitch directions were (0.63±0.48) cm vs.(0.33±0.24) cm (P=0.000),(0.40±0.3) cm vs.(0.31±0.25) cm (P=0.000),(0.69±0.61) cm vs.(0.82±0.69) cm (P=0.006),0.65°±0.47°vs 0.32°±0.25°(P=0.000),1.05°±0.95°vs 1.16°±0.94° (P=0.100) and 0.67°±0.56°vs 0.40°±0.36° (P=0.000),respectively.The maximum setup errors were detected in the pitch direction for both groups.Conclusions During the proton and carbon therapy using Siemens 6D robotic couch,two setup methods using vacuum bag plus body mask and customized alpha cradle should be selected according to the individual conditions of patients.A customized foot fixer should be utilized to reduce the uncertainty in the femoral head region.