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Objective:To investigate the clinical efficacy and prognostic factors of 125I seeds implantation in the treatment of patients with advanced lung cancer after radiotherapy and chemotherapy. Methods:From January 2017 to December 2019, 44 patients (39 males, 5 females, age 41-84 years) with advanced lung cancer after radiotherapy and chemotherapy who received 125I seeds implantation in Hebei General Hospital were retrospectively analyzed. All patients were followed up for ≥12 months, and the clinical efficacies were observed. χ2 test was used to analyze the difference of effective rates between groups. The cut-off value of postoperative dose delivered to 90% gross tumor volume ( D90) was obtained by ROC curve analysis. Kaplan-Meier method was used to calculate the survival rate and log-rank test was used for univariate analysis. Cox proportional hazards model was used for multivariate analysis to find the influencing factors for clinical efficacy. Results:The total effective rate was 72.73%(32/44) after 6 months treatment. The cut-off value of D90 was 120 Gy with the AUC of 0.771. The short-term effective rate of D90≥120 Gy group was better than that of D90<120 Gy group (18/19 vs 56.00%(14/25); χ2=8.17, P=0.004). The 1-year survival rate was 77.27%(34/44). Univariate analysis showed that age ( χ2=3.99, P=0.046), preoperative Hb ( χ2=10.60, P=0.001), tumor maximum diameter ( χ2=11.50, P=0.001) and postoperative D90( χ2=5.81, P=0.016) could affect the survival of patients. Multivariate analysis showed that preoperative Hb (hazard ratio ( HR)=0.023, 95% CI: 0.001-0.882, P=0.043) and tumor maximum diameter ( HR=40.889, 95% CI: 1.458-1 146.586, P=0.029) were prognostic factors. Conclusions:125I seeds implantation shows a good effect in the treatment of lung cancer patients after the progress of radiotherapy and chemotherapy. The short-term effect of patients with D90≥120 Gy is better than that of patients with D90<120 Gy. Preoperative Hb and tumor maximum diameter are prognostic factors of survival after implantation.
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Objective:To investigate the relationship between dosimetric parameters and tumor volume change after 125I implantation for thyroid cancer and obtain better dosimetric parameters that predict the curative effect more accurately. Methods:A total of 22 consecutive patients with thyroid cancer (23 targets) who received 125I interstitial brachytherapy in Department of Oncology, Hebei General Hospital were retrospectively analyzed. All the patients received post-operative dose verification, and the D 90 (Minimum dose received by 90% target volume) was calculated. After a regular follow-up, the tumor volume reduction ratio after t months (R t) , actual absorbed dose (D 1m) , efficacy corrected absorbed dose (D 1e) , and sensitivity corrected absorbed dose (D 1s) of the first month were calculated according to the actual follow-up CT images. The statistical test was carried out by SPSS21.0. The Spearman linear analysis was applied to analyze the relationship between D 90, D 1m, D 1e, D 1s and R t, and the curve fitting was also completed. Results:The post-operative D 90, D 1m, D 1e, D 1s and R t were (129.73±14.22) Gy, (36.95±7.35) Gy, (43.45±11.32) Gy, (41.78±13.39) Gy, and (32.00±19.00) %, respectively. And the correlation coefficient were 0.692, 0.551, 0.728, and 0.858, respectively, which showed significant positive relevance between dosimetric parameters and tumor volume change ( P<0.01) , the curve fitting presented cubic function. Conclusion:The post-operative D 90, D 1m, D 1e, and D 1s can be predictors for curative effect, and D 1s is the best predictor.
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Objective To analyze the factors influencing the short-term efficacy of CT-guided 125I seeds implantation in the treatment of recurrent and metastatic tumors in head and neck.Methods A total of 73 patients (61 males,12 females;age:(59.1±11.5) years) with head and neck tumors recurrence and metastasis treated by 125I seeds implantation in Hebei General Hospital from January 2015 to April 2019 were retrospectively enrolled.The implanted seeds activity was 11.1-29.6 MBq,and the prescription dose was 80.0-145.0 Gy.CT examination was conducted 3 months after 125I seeds implantation.According to Response Evaluation Criteria in Solid Tumors (RECIST) 1.1,short-term efficacy was classified as effective (complete remission (CR),partial remission (PR)) and ineffective (stable disease (SD),progressive disease (PD)).Univariate analysis of factors affecting short-term effect (gender,age,history of radiation therapy,Karnofsky performance status (KPS) scores,pathological type,the longest diameter of tumor,implantation patterns,seeds activity,immediate postoperative dose delivered to 90％ gross tumor volume (D90),and with adjuvant chemotherapy post-surgery or not) were conducted.Variables with P＜ 0.2 were enrolled in logistic multivariate regression analysis.In addition,artificial neural network (ANN) was constructed with all influencing factors as independent variables and short-term efficacy as dependent variables.Finally,receiver operating characteristic (ROC) curve analysis was performed for the common influencing factors in logistic regression analysis and ANN analysis.Results There were 34 with effective results and 39 with ineffective results.Logistic regression analysis indicated that the longest diameter of tumor,immediate postoperative D90,with adjuvant chemotherapy post-surgery or not had significant impacts on the shortterm efficacy (Wald values:6.950,4.804,4.790,all P＜0.05);According to results of ANN analysis,the top 5 in order of importance for short-term efficacy prediction were immediate postoperative D90,the longest diameter of tumor,age,seeds activity and gender.ROC curve analysis indicated that the longest diameter of tumor and immediate postoperative D90 were the best predictors for short-term efficacy,with the threshold of 5.25 cm and 110.05 Gy respectively,and the area under the curve (AUC) was 0.843 and 0.847 respectively (both P＜0.001).Conclusions The short-term efficacy of 125I seeds implantation in the recurrence and metastasis of head and neck tumors is mainly related to the longest diameter of tumor and immediate postoperative D90.Patients with the longest diameter of tumor ＜5.25 cm and with D90＞110.05 Gy can achieve better efficacy.
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Objective@#To analyze the factors influencing the short-term efficacy of CT-guided 125I seeds implantation in the treatment of recurrent and metastatic tumors in head and neck.@*Methods@#A total of 73 patients (61 males, 12 females; age: (59.1±11.5) years) with head and neck tumors recurrence and metastasis treated by 125I seeds implantation in Hebei General Hospital from January 2015 to April 2019 were retrospectively enrolled. The implanted seeds activity was 11.1-29.6 MBq, and the prescription dose was 80.0-145.0 Gy. CT examination was conducted 3 months after 125I seeds implantation. According to Response Evaluation Criteria in Solid Tumors (RECIST) 1.1, short-term efficacy was classified as effective (complete remission (CR), partial remission (PR)) and ineffective (stable disease (SD), progressive disease (PD)). Univariate analysis of factors affecting short-term effect (gender, age, history of radiation therapy, Karnofsky performance status (KPS) scores, pathological type, the longest diameter of tumor, implantation patterns, seeds activity, immediate postoperative dose delivered to 90% gross tumor volume (D90), and with adjuvant chemotherapy post-surgery or not) were conducted. Variables with P<0.2 were enrolled in logistic multivariate regression analysis. In addition, artificial neural network (ANN) was constructed with all influencing factors as independent variables and short-term efficacy as dependent variables. Finally, receiver operating characteristic (ROC) curve analysis was performed for the common influencing factors in logistic regression analysis and ANN analysis.@*Results@#There were 34 with effective results and 39 with ineffective results. Logistic regression analysis indicated that the longest diameter of tumor, immediate postoperative D90, with adjuvant chemotherapy post-surgery or not had significant impacts on the short-term efficacy (Wald values: 6.950, 4.804, 4.790, all P<0.05); According to results of ANN analysis, the top 5 in order of importance for short-term efficacy prediction were immediate postoperative D90, the longest diameter of tumor, age, seeds activity and gender. ROC curve analysis indicated that the longest diameter of tumor and immediate postoperative D90 were the best predictors for short-term efficacy, with the threshold of 5.25 cm and 110.05 Gy respectively, and the area under the curve (AUC) was 0.843 and 0.847 respectively (both P<0.001).@*Conclusions@#The short-term efficacy of 125I seeds implantation in the recurrence and metastasis of head and neck tumors is mainly related to the longest diameter of tumor and immediate postoperative D90. Patients with the longest diameter of tumor <5.25 cm and with D90>110.05 Gy can achieve better efficacy.
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Objective: The objective of the study is to test whether three-dimensional (3D)-printed template can be used reproducibly for guiding malignant tumors brachytherapy and study the dosimetric consistency and adequacy between pre- and post-plan. Materials and Methods: Between January and December 2016 in our hospital, a total of 14 patients underwent 3D-printed template-guided brachytherapy. All the patients were fixed into position using a vacuum cushion before undertaking a computed tomography (CT) scan. After the preplan was designed, the templates were printed. The tumors were punctured through predesigned needle holes. Following this, another CT scan was used to confirm the locations of needles, and then the 125 I radioactive seeds were implanted into the tumor according to the preplan. Postplan was performed after the operation. Data of the D90 (minimum absorbed dose of 90% target volume), V90 (90% prescription dose coverage volume percentage of target volume), V100, V150, and seed number pre- and post-operation were collected and compared. Results: The mean D90, V90, V100, V150, and seed number preoperation were 94.96 ± 16.43 Gy, 94.64% ± 1.43%, 91.21% ± 1.59%, 65.01% ± 5.78%, and 46.67 ± 21.87, respectively. The mean D90, V90, V100, V150, and seed number postoperation were 91.97 ± 17.54 Gy, 93.35% ± 2.45%, 89.35% ± 3.21%, 63.40% ± 6.36%, and 46.60 ± 22.85, respectively. No significant difference between pre- and post-operation was observed across the data (P >0.05). Conclusion: For immobilized malignant tumors, 3D-printed template can be used reproducibly. The dose parameters in preplan can be achieved easily and satisfactorily by 3D-printed template guided brachytherapy, and it may become an easily reproducible standardized procedure in the future
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Objective To explore the relationship between the peripheral dose and radioactive counts of 125I seeds detected by SPECT/CT.Methods Six 125I seeds(1.48×107 Bq, 1.85×107 Bq, 2.22×107 Bq, 2.59×107 Bq, 2.96×107 Bq, 3.33×107 Bq) were put into the solid water phantoms respectively. SPECT/CT was applied to scan the seeds. The radioactive counts (x) at the distance of 1-15 mm from the center of seeds were recorded respectively, while the corresponding doses (y, cGy) were calculated. SPSS 18.0 was used to analyze the relationship between the radioactive counts and peripheral dose. Results There was an exponential relationship between the peripheral dose of 125I seeds and the radioactive counts. The formula was as follow: y=507.849×1.004x. Conclusion SPECT/CT can visualize the peripheral dose of 125I seed, which may provide a method for dosimetric verification after brachytherapy.
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Objective To investigate the dosimetric effect of same activity and same number of 125I seeds arranged in axial train but with different spacing.Methods A total of 27 film dosimeters were randomly and equally divided into group A,B and C.Each film was irradiated by three 125I seeds (activity of 1.48×107 Bq).The seeds were arranged in line,and their axial spacing was 1 mm,5 mm and 10 mm respectively.Image analysis software was used to draw iso-gray contour curves of 20,25,30 and 40 gray value on the films,and to calculate the areas contained by each curve.Results Multi-sample mean comparison variance analysis showed that the differences in area contained by 20 and 25 iso-gray contour curves were statistically significant between each other among the three groups (P＜0.001).The difference in area contained by 30 iso-gray contour curve between group A and group B was not statistically significant (P＞ 0.05),while the difference in area contained by 30 iso-gray contour curve between group A and group C as well as between group B and group C was statistically significant (P＜0.001).No statistically significant difference in area contained by 40 iso-gray contour curve existed between each other among the three groups (P=0.99).Conclusion Different spacing arrangement of same activity and same number of 125I seeds can directly influence the peripheral dose distribution.In specific dose range,seed-spacing of 1 mm arrangement may obtain better dose distribution than seed-spacing of 5 mm or 10 mm arrangement can do.
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Objective To discuss the necessity and feasibility of intraoperative use of treatment planning system (TPS) to make real-time planning for the treatment of retroperitoneal metastatic carcinoma with CT-guided 125I seed brachytherapy.Methods The clinical data of 20 patients with retroperitoneal lymph node metastases,who received CT-guided 125I seed brachytherapy during the period from January 2013 to December 2015,were retrospectively analyzed.The patients were divided into group A (n=10) and group B (n=10).The intraoperative TPS was employed to formulate the real-time planning for the patients of group A,while real-time planning was not adopted for the patients of group B.The quality verification of preoperative planning and postoperative effect was conducted for the patients of both groups.Comparing the preoperative and postoperative absorbed dose,the minimum absorbed dose (D90) error percentage of 90％ target volume,the error percentage of the covered volume by 90％ prescription dose to the target volume (V90),the error percentage of the covered volume by 100％ prescription dose to the target volume (V100),and the error percentage of the covered volume by 150％ prescription dose to the target volume (V150) were calculated in all patients of both groups,and the results were statistically analyzed.Results The mean error percentage of D90,V90,V100,V150 in group A were (-1.30±6.80) Gy,(-0.60±2.10)％,(-0.47±2.70)％ and (89.60±282.00)％ respectively,which in group B were (-9.33±46) Gy,(11.50±13.7)％,(-13.40±15.90)％ and (10.37±2.00)％ respectively.The differences in the error percentage of D90,V90 and V100 between group A and group B were statistically significant (P＜0.05 in all),while no statistically significant difference in the error percentage of V150 existed between group A and group B (P＞0.05).Conclusion The use of intraoperative TPS real-time planning can significantly improve the consistency of target region dose before and after seed implantation and make the dose distribution more reasonable,which is of great value for the standardization of CT-guided 125I seed brachytherapy of retroperitoneal lymph node metastases.