Aim: To analyze the inter-fraction, intra-fraction uncertainties and to verify the delivered total dose with planned dose in the combined intracavitary-interstitial brachytherapy of gynaecological cancer patients usin...Aim: To analyze the inter-fraction, intra-fraction uncertainties and to verify the delivered total dose with planned dose in the combined intracavitary-interstitial brachytherapy of gynaecological cancer patients using microMOSFET in-vivo dosimeter. Materials and Methods: Between May 2014 and March 2016, 22 patients who underwent brachytherapy treatments with an applicator combination of CT/MR compatible tandem, ring and Syed-Neblett template-guided rigid needles were included in this study. Specially designed microMOSFET, after calibration, was used to analyze the variations in dosimetry of combined intracavitary-interstitial application. Results: The standard deviation for Inter-fraction variation among 22 combined intracavitary interstitial applications ranged between 0.86% and 10.92%. When compared with the first fraction dose, the minimum and maximum dose variations were −9.5% and 26.36%, respectively. However, the mean doses varied between −5.95% and 14.49%. Intra-fraction variation, which is the difference of TPS calculated dose with first fraction microMOSFET-measured dose ranges from −6.77% to 8.68%. The variations in the delivered total mean dose in 66 sessions with planned doses were −3.09% to 10.83%. Conclusions: It is found that there was a gradual increase in microMOSFET measured doses as compared to the first fraction with that of subsequent fractions in 19 out of 22 applications. Tumor deformation and edema may be the influencing factors, but the applicator movements played a major role for the variations. We find that the microMOSFET is an easy and reliable system for independent verification of uncertainties during ICBT-ISBT treatments.展开更多
AIM:To develop a fuzzy classification method to score the texture features of pancreatic cancer in endoscopic ultrasonography(EUS)images and evaluate its utility in making prognosis judgments for patients with unresec...AIM:To develop a fuzzy classification method to score the texture features of pancreatic cancer in endoscopic ultrasonography(EUS)images and evaluate its utility in making prognosis judgments for patients with unresectable pancreatic cancer treated by EUS-guided interstitial brachytherapy.METHODS:EUS images from our retrospective database were analyzed.The regions of interest were drawn,and texture features were extracted,selected,and scored with a fuzzy classification method using a C++program.Then,patients with unresectable pancreatic cancer were enrolled to receive EUS-guided iodine 125 radioactive seed implantation.Their fuzzy classification scores,tumor volumes,and carbohydrate antigen 199(CA199)levels before and after the brachytherapy were recorded.The association between the changes in these parameters and overall survival was analyzed statistically.RESULTS:EUS images of 153 patients with pancreatic cancer and 63 non-cancer patients were analyzed.A total of 25 consecutive patients were enrolled,and they tolerated the brachytherapy well without any complications.There was a correlation between the change in the fuzzy classification score and overall survival(Spearman test,r=0.616,P=0.001),whereas no correlation was found to be significant between the change in tumor volume(P=0.663),CA199 level(P=0.659),and overall survival.There were 15 patients with a decrease in their fuzzy classification score after brachytherapy,whereas the fuzzy classification score increased in another 10 patients.There was a significant difference in overall survival between the two groups(67 d vs 151 d,P=0.001),but not in the change of tumor volume and CA199 level.CONCLUSION:Using the fuzzy classification method to analyze EUS images of pancreatic cancer is feasible,and the method can be used to make prognosis judgments for patients with unresectable pancreatic cancer treated by interstitial brachytherapy.展开更多
Background: The aim of breast-conserving treatment (BCT) in breast cancer, consisting of wide local excision (WLE) and radiotherapy, is to obtain local control of disease as well as an optimal cosmetic result. The app...Background: The aim of breast-conserving treatment (BCT) in breast cancer, consisting of wide local excision (WLE) and radiotherapy, is to obtain local control of disease as well as an optimal cosmetic result. The application of perioperative brachytherapy allows more precise deposition of the boost radiation dose to the lumpectomy cavity plus margins in a shorter period of time, as compared to external beam radiotherapy. The aim of the present study was to analyze the oncological outcome of interstitial brachytherapy in our patient population of patients with early-stage breast cancer. Patients and Methods: 107 breasts in 105 patients with T1-2 breast cancer were treated between 1996 and 2009 with BCT, including WLE combined with perioperative brachytherapy using Iridium-192 (15 Gy with low dose rate or 9 Gy with high dose rate) followed by whole breast irradiation (50 Gy). Outcomes analyzed included treatment toxicity (according to Common Terminology Criteria for Adverse Events), local recurrence rate, and disease-free and overall survival. Results: Median follow-up of patients still alive was 6.3 years (range 2.0 - 14.5). Mean age was 50.2 years (+/- S.D. 10.5). Mean tumor diameter was 15 mm (+/- S.D. 8 mm. Acute complications consisted of grade 1 and 3 complications, respectively n = 8 and n = 1. Late complications consisted of grade 1 or 2, respectively n = 25 and n = 2. Only three patients (2.8%) developed a local recurrence with a median time to recurrence of 9.3 years (range 3.3 - 9.3). Five- and ten-year local recurrence free survival was 99% and 91%, respectively. Five- and ten-year disease-specific and overall survival was 95% and 84% versus 92% and 78%, respectively. Conclusions: Treatment-related toxicity after brachytherapy for breast cancer was mild. The local recurrence rate is low. Therefore, brachytherapy is a good alternative to conventional radiation boost as a part of breast irradiation in breast conserving treatment in early stage breast cancer.展开更多
Background: The delivered dose has to be checked and verified with planned dose since precise and accurate dose delivery is essential in Brachytherapy. Sources of uncertainty during Brachytherapy are intra-fraction, i...Background: The delivered dose has to be checked and verified with planned dose since precise and accurate dose delivery is essential in Brachytherapy. Sources of uncertainty during Brachytherapy are intra-fraction, inter-fraction and inter-application variations. In-vivo dosimetry is the direct method to monitor the radiation dose delivered to a patient during radiotherapy. In this study, assessment of the inter-fraction and intra-fraction variations in the interstitial Brachytherapy was done with microMOSFET. Aim: To analyze the inter-fraction variations in dose delivery during interstitial HDR Brachytherapy and to compare the measured point dose with the TPS-calculated point dose, intra-fraction variation, using the microMOSFET in-vivo dosimeter. Materials and Methods: From May 2014 to February 2016, 22 patients with Head and Neck cancers and 8 patients with Soft-Tissue Sarcomas (STS) were selected for this study. All these patients underwent CT imaging more than 24 hours after the application. Brachyvision 3DTPS and GammaMed Plus iX HDR unit were used for treatments. MicroMOSFET in-vivo dosimeter after calibration was used for the measurements of dose inside the treated volume. Intra & Inter-fraction variations were analyzed and reported. Results: The SD of inter-fraction variation among 22 Head & Neck patients ranges from 2.14% to 14.26%. Minimum & maximum dose variation with first fraction dose of patients ranged from -22.33% to +26.71% and the mean doses were -6.42% to +19.76%. Differences of TPS dose and microMOSFET measured first fraction dose, intra-fraction variation, ranged from -12.36% to +5.05%. The SD of inter-fraction variation for 8 STS patients was from 2.81% to 14.43%. Minimum and maximum doses vary from -38.72% to +25.74% and mean dose varies from -21.5% to +12.53%. Differences of point doses of TPS and measured, intra-fraction variation, were from -5.86% to 4.88%. Conclusions: MicroMOSFET has the potential to minimize the gross errors during multi-fractionated Interstitial Brachytherapy. Edema, applicator displacements and placement of microMOSFET are the main influencing factors for inter-fraction uncertainty in dose delivery. Re-planning with re-simulated images should be considered whenever the microMOSFET readings vary more than ±10% of the planned dose inside the CTV measured in two successive fractions.展开更多
The study was intended to highlight functional outcome and survival advantage when High Dose Rate (HDR) interstitial implant was used for anterior 2/3rd tongue, either as a primary or as boost depending upon stage of ...The study was intended to highlight functional outcome and survival advantage when High Dose Rate (HDR) interstitial implant was used for anterior 2/3rd tongue, either as a primary or as boost depending upon stage of disease. Materials and Methods: Fifty-one patients with squamous cell carcinoma of anterior 2/3rd tongue received interstitial brachytherapy either as primary or as boost with Iridium 192 remote after loading high dose rate (Microselectron or Gamma MediX) machines from November 2008 to September 2013. Age group ranged from 32 to 73 years, mean 52.1. Of these 51, 37 were males and 14 were females. 8 patients belonged to Stage I, 18 from Stage II and 28 patients were Stage III. Stage I patients received primary brachytherapy alone of dose 38.50 Gy to 40 Gy and fraction dose ranged from 250 cGy to 350 cGy. Stage II and Stage III patients received external beam radiation of dose 44 Gy/200cGy per fraction for 22 fractions followed by spinal cord sparing for 6 Gy/200cGy per fraction for 3 fractions. Brachytherapy boost of dose 21 Gy was delivered after external beam radiation. Stage III patients received concurrent chemotherapy with Injection Cisplatin along with external beam radiotherapy 44 Gy/200cGy per fraction for 22 fractions followed by spinal cord sparing for 6 Gy/200cGy per fraction for 3 fractions. Brachytherapy boost of dose 21 Gy was delivered after external beam radiation. 55% of patients were habituated to tobacco and alcohol in one form or the other or both. Surprisingly 45% of patients were nonsmokers and non-alcoholic. Results: Follow-up period ranged from eight months to sixty months. 42 patients had complete response. 9 patients had residual disease. 2 patients died due to non-cancerous cause though they had excellent local control, one with pulmonary tuberculosis and the other with massive Myocardial Infarction. 2 patients died due to disease progression. Overall complete response rate was 82.35%. Those patients who had good coverage index and conformal index had good response compared to those patients with lesser these values. Conclusion: It is surprising to observe from the study that oral cavity cancers are not uncommon in non-smokers and non-alcoholics. Overall complete response of 82% is comparable to any other study quoted in literature. Surgery offers same cure rate but at the rate of organ loss and functional impairment. Organ preservation with good functional outcome is possible in radiotherapy unlike surgery. This study proves brachytherapy can be considered as a surrogate to surgery in early stage tongue cancers with good functional outcome and with lesser morbidity.展开更多
Background: Patient setup errors in External Beam Radiotherapy (EBRT) are minimized to a great extent, due to recent technological developments but in contrary brachytherapy received least attention in inter-fraction ...Background: Patient setup errors in External Beam Radiotherapy (EBRT) are minimized to a great extent, due to recent technological developments but in contrary brachytherapy received least attention in inter-fraction catheter movement and its impact in dose delivery. This article deals with inter-fraction interstitial catheter movement and its impact in dose delivery to the target. An attempt is made to study the dosimetric impact of this variation. Objectives: The objective of the study is to evaluate the inter-fraction variation in the position of implanted interstitial applicators and to assess the dosimetric impact in interstitial High Dose Rate (HDR) brachytherapy. Materials and Methods: 55 patients treated for carcinoma tongue, breast, buccal mucosa, cervix, floor of mouth and soft tissue sarcoma over a period of 2 years (December 2011-May 2013) were considered. All the patients underwent CT scan on the next day of the implant and 3D planning was done either by Eclipse or Oncentra Master plan Treatment Planning System (TPS). Patients were treated by HDR brachytherapy remote after-loading units, either by Gamma Med iX plus or Microselectron. At the end of the last fraction, CT scan was repeated and re-planning done. The variation in position of the implanted applicators/catheters and its impact on dosimetric parameters were evaluated and analyzed. Results: The range of positional displacement of the interstitial catheters ranges from 4.5 mm to 6.8 mm. The maximum variation in prescribed dose to D90 of Clinical Target Volume was 10.88%. Conclusions: If the total duration of interstitial implant of HDR brachytherapy extends for more than a week from the day of imaging, it is recommended to do CT imaging and re-plan again. It is mandatory to suture the buttons of the implant to the skin. Edema and movement of organs (e.g., tongue) are the main cause for the positional variation of the catheters.展开更多
Objective:The aim of our study was to explore the influence of interstitial brachytherapy with 125I seeds on Caspase-3 and Egr-1 expressions of Lewis lung carcinoma in C57BL mice.Methods:Model mice of C57BL were plant...Objective:The aim of our study was to explore the influence of interstitial brachytherapy with 125I seeds on Caspase-3 and Egr-1 expressions of Lewis lung carcinoma in C57BL mice.Methods:Model mice of C57BL were planted with Lewis lung cells (LLC) and divided into the treatment group (n=18) and the control group (n=17).In each mouse of the treatment group,two BT-125-1 Model 125I seeds with apparent activity of 9.25 MBq were implanted into the tumor;whereas in each mouse of the control group two dummy seeds were implanted.The mice survival rates of both groups were recorded after 21 days.The tumor weights and dimensions of survived mice were measured,and the tumor volume inhibition rate was calculated.T-test was performed to compare differences of tumor weights and volumes between these two groups.Routine pathological slides of tumor tissue were observed under light microscope.The expression of Caspase-3 was detected by immunohistochemical method and the expression of Egr-1 was detected by RT-PCR method.Results:The survival rates were 88.88% in the treatment group and 70.59% in the control group,the difference had no statistical significance (P > 0.05).The tumor volume inhibition rate was 71.12%.Pathological examination showed degeneration and necrosis of cancer cells at the site nearby the seed in the treated group,but the tumor cells alive were still presented nearby the seed in the control group.The expressions of Caspase-3 and Egr-1 in the treated group were higher than those in the control group (t=12.825,P < 0.01;t=7.039,P < 0.01;respectively).Conclusion:The interstitial brachytherapy with 125I seeds could significantly inhibit the growth of Lewis lung carcinoma of mice.The possible mechanism may be that 125I interstitial brachytherapy can enhance the expressions of Egr-1 and Caspase-3,which could induce tumor cellular apoptosis.展开更多
Background: Treatment of Cervical cancer includes a combination of external beam radiotherapy (EBRT) with intracavitary brachytherapy (ICBT). ICBT helps to boost radiation dose to primary disease. Organs like rectum, ...Background: Treatment of Cervical cancer includes a combination of external beam radiotherapy (EBRT) with intracavitary brachytherapy (ICBT). ICBT helps to boost radiation dose to primary disease. Organs like rectum, bladder, sigmoid and small bowel lie close to the cervix region and these organs receive dose from EBRT as well as ICBT and we want to know the dose to these organ at risk (OAR). Materials & Methods: Dosimetric details of 174 ICBT applications done in 58 patients were retrospectively analysed. All patients received EBRT dose of 50.4 Gy in 28 fractions. All patients had ICBT, three sessions with 7 Gy prescribed to point A. Dosimetric data including dose to right and left point A and dose to OARs were recorded from Oncentra Planning System. Results: Mean dose to point A on right side was 6.89 Gy and left side was 6.91 Gy. Mean D2cc dose to rectum, bladder, sigmoid and small bowel was 3.5 Gy, 5.25 Gy, 4.75 Gy and 4.2 Gy respectively. Mean EQD2 dose combining EBRT and ICBT in point A was 78.7 Gy on right side and 79 Gy on left side. Mean EQD2 doses to D2cc of rectum, bladder, sigmoid and small bowel was 62 Gy, 74.4 Gy, 70.5 Gy and 66.5 Gy respectively. Conclusion: From the results of this dosimetric study it is evident that OARs like rectum, sigmoid, bladder & bowel are receiving only acceptable doses of radiation using point A prescribed CT based ICBT planning. Hence with regards to OAR doses, CT based ICBT planning with dose prescribed to point A is a feasible option.展开更多
Purpose: Curative radiation therapy is an established treatment option for non-surgical patients with early-stage endometrial carcinoma. Dosimetric analyses were performed using a single tandem, double tandem, Heyman ...Purpose: Curative radiation therapy is an established treatment option for non-surgical patients with early-stage endometrial carcinoma. Dosimetric analyses were performed using a single tandem, double tandem, Heyman capsules, and an inflatable intrauterine balloon to assess the dose homogeneity and conformality in the definitive treatment of inoperable endometrial cancer. Methods and Materials: Patients’ informed-consent was obtained. Dosimetric analyses were performed using four different after-loading applicators to assess the dose homogeneity and conformality of isodose to the three-dimensional (3-D) shape of the target volume (uterus) based on CT data in four patients (n = 4). The single tandem and double tandems were standard Fletcher-type (Nucletron Corporation, Columbia, MD). Heyman capsules were the disposable after-loading type (Radiation Products Design, Inc., Albertville, MN). The inflatable balloon with a central bi-lumen catheter was the Mammo Site Radiation Therapy System (Proxima Therapeutics, Alpharetta, GA) that is currently used for local breast brachytherapy. Treatment planning and dosimetric analyses for all four techniques were done with HDR PLATO Brachytherapy (v14.2.3) Software (Nucletron Corporation). Results: The average dose gradient within the target (uterine wall) is highest with the tandem methods, followed by Heyman capsules. The intrauterine balloon method showed the least dose gradient across the uterine wall. The corresponding average homogeneity indices were 3.81, 3.83, 2.97, 2.50 for single tandem, double tandem, Heyman capsules, and intrauterine balloon respectively. Conclusions: The intra-uterine inflatable balloon appears to have the best overall dosimetric advantages for the treatment of the uterine wall. Furthermore, the potential ease of use, shorter time of applicator placement, and better patient comfort warrant further investigation and subsequent clinical implementation.展开更多
Objective:To observe the effects of Methyl Carboprost and Diclofenac Sodium on opening orifice of uterus and pain controlling in patients with uterine cervix cancer (UCC) when receiving intracavitary brachytherapy. Me...Objective:To observe the effects of Methyl Carboprost and Diclofenac Sodium on opening orifice of uterus and pain controlling in patients with uterine cervix cancer (UCC) when receiving intracavitary brachytherapy. Methods: Sixty patients with UCC of stage IIA-IIIB were divided into three groups randomly before receiving the intracavitary brachytherapy: the patients in group A received Methyl Carboprost in the hind fornix of the vagina, group B received Diclofenac Sodium in the anus, while group C was the control group. Results: The painlessness rates in groups A, B and C were 89.9%, 91.3% and 36.4%, respectively. The incidences of patients with relaxed uterus cervix in groups A, B and C were 91.7%, 85.9% and 48.9%, respectively. Conclusion: Methyl Carboprost and Diclofenac Sodium are useful in relaxing uterus cervix and pain controlling in patients with UCC when receiving intracavitary brachytherapy.展开更多
Objective: The aim of our study was to evaluate the outcome and complications of cervical cancer patients undergoing conventional intracavitary brachytherapy (ICBT) treated with 3D-conformal radiotherapy (3DCRT). Meth...Objective: The aim of our study was to evaluate the outcome and complications of cervical cancer patients undergoing conventional intracavitary brachytherapy (ICBT) treated with 3D-conformal radiotherapy (3DCRT). Methods: Sixty cervical cancer patients were divided randomly into the conformal group and the conventional group. Thirty patients treated with 3D-conformal radiotherapy in the 3DCRT group, when the whole pelvic received DT 40 Gy, a planning CT scan of each patient was obtained and the second 3DCRT therapy plan was taken. Then, continued to irradiate to 50 Gy. At last, 3DCRT was boosted at local involved volumes to the total dose of 60 Gy. When 3DCRT was combined with intracavitary brachytherapy, the dose of brachytherapy to point A was 30 Gy/5 fractions. In the conventional group, after a total tumor dose of 40 Gy was delivered by the whole pelvic irradiation, the four-field technique was used to irradiate the total pelvic and regional nodes (median dose of 10 Gy), and the involved volumes were boosted to 60 Gy and the dose of brachytherapy to point A was 30 Gy-36 Gy/5-6 fractions. Moreover, both groups were combined with intracavitary brachytherapy respectively. Results: The 1, 2, 3-year survival rates for the 3DCRT group and the conventional group were 96.7%, 93.3%, 90.0% and 86.6%, 76.7%, 70% respectively (P = 0.04, P = 0.02 and P = 0.02). There was a statistically significant difference between the two groups. Compared to the two groups each other in toxic effects, except for the I-II grade rectal and bladder reaction and pelvic fibrosis which was lower in the 3DCRT group (P = 0. 007, P = 0. 006 and P = 0. 015), the side effects were similar and well tolerated in two groups. Conclusion: The all-course 3DCRT combined with intracavitary brachytherapy can be considered as an effective and feasible approach to cervical cancer and may significantly improve the survival rate and reduce the late toxicity. This new role for 3DCRT merits need further evaluation with large patient numbers and longer follows up.展开更多
OBJECTIVE To evaluate the results and complications associated with nasopharyngeal carcinoma (NPC) treated with combined external-beam radiotherapy (EBR) and intracavitary brachytherapy (IB) using a new-type app...OBJECTIVE To evaluate the results and complications associated with nasopharyngeal carcinoma (NPC) treated with combined external-beam radiotherapy (EBR) and intracavitary brachytherapy (IB) using a new-type applicator. METHODS Eighty patients with untreated NPC were divided into two groups based on therapy methods. An experimental group was treated with EBR plus IB and a control group was treated only with EBR. IB was given to the patients of the experimental group when the external radiotherapy dose amounted to more than 60~65 Gy. The total dose of IB was 6~20 Gy and the total dose of EBR of the control group was 70~75 Gy. RESULTS Follow-up was conducted for 97.5% of the patients with re- suits as follows: the overall response rates (ORR) for the experimental and the control groups were 92.5% and 75.3% respectively (P〈0.05); the 3 and 5-year survival rates for the experimental group were 87.5% and 74.2% and for the control group, 65.0% and 55.6% (P〈0.05); for the experimental group, the 3 and 5-year disease-free survival rates were 72.5% and 64.5% and for the control group, 60.0% and 52.8% (P〉0.05).Some complications following radiotherapy showed a significant difference. CONCLUSION External irradiation plus intracavitary brachytherapy using a new-type applicator may improve the ORR and survival rates, reduce radiation complications and increase the quality of life. 展开更多
Brachytherapy forms an integral part of the radiation therapy in cancer cervix. The dose prescription for intracavitary brachytherapy(ICBT) in cancer cervix is based on Tod and Meredith's point A and has been in p...Brachytherapy forms an integral part of the radiation therapy in cancer cervix. The dose prescription for intracavitary brachytherapy(ICBT) in cancer cervix is based on Tod and Meredith's point A and has been in practice since 1938. This was proposed at a time when accessibility to imaging technology and dose computation facilities was limited. The concept has been in practice worldwide for more than half a century and has been the fulcrum of all ICBT treatments, strategies and outcome measures. The method is simple and can be adapted by all centres practicing ICBT in cancer cervix. However, with the widespread availability of imaging techniques, clinical use of different dose-rates, availability of a host of applicators fabricated with image compatible materials, radiobiological implications of dose equivalence and its impact on tumour and organs at risk; more and more weight is being laid down on individualised image based brachytherapy. Thus, computed tomography, magnetic-resonance imaging and even positron emission computerized tomographyalong with brachytherapy treatment planning system are being increasingly adopted with promising outcomes. The present article reviews the evolution of dose prescription concepts in ICBT in cancer cervix and brings forward the need for image based brachytherapy to evaluate clinical outcomes. As is evident, a gradual transition from "point" based brachytherapy to "profile" based image guided brachytherapy is gaining widespread acceptance for dose prescription, reporting and outcome evaluation in the clinical practice of ICBT in cancer cervix.展开更多
文摘Aim: To analyze the inter-fraction, intra-fraction uncertainties and to verify the delivered total dose with planned dose in the combined intracavitary-interstitial brachytherapy of gynaecological cancer patients using microMOSFET in-vivo dosimeter. Materials and Methods: Between May 2014 and March 2016, 22 patients who underwent brachytherapy treatments with an applicator combination of CT/MR compatible tandem, ring and Syed-Neblett template-guided rigid needles were included in this study. Specially designed microMOSFET, after calibration, was used to analyze the variations in dosimetry of combined intracavitary-interstitial application. Results: The standard deviation for Inter-fraction variation among 22 combined intracavitary interstitial applications ranged between 0.86% and 10.92%. When compared with the first fraction dose, the minimum and maximum dose variations were −9.5% and 26.36%, respectively. However, the mean doses varied between −5.95% and 14.49%. Intra-fraction variation, which is the difference of TPS calculated dose with first fraction microMOSFET-measured dose ranges from −6.77% to 8.68%. The variations in the delivered total mean dose in 66 sessions with planned doses were −3.09% to 10.83%. Conclusions: It is found that there was a gradual increase in microMOSFET measured doses as compared to the first fraction with that of subsequent fractions in 19 out of 22 applications. Tumor deformation and edema may be the influencing factors, but the applicator movements played a major role for the variations. We find that the microMOSFET is an easy and reliable system for independent verification of uncertainties during ICBT-ISBT treatments.
基金Supported by The National Natural Science Foundation of China,No.30801362 and 81001074
文摘AIM:To develop a fuzzy classification method to score the texture features of pancreatic cancer in endoscopic ultrasonography(EUS)images and evaluate its utility in making prognosis judgments for patients with unresectable pancreatic cancer treated by EUS-guided interstitial brachytherapy.METHODS:EUS images from our retrospective database were analyzed.The regions of interest were drawn,and texture features were extracted,selected,and scored with a fuzzy classification method using a C++program.Then,patients with unresectable pancreatic cancer were enrolled to receive EUS-guided iodine 125 radioactive seed implantation.Their fuzzy classification scores,tumor volumes,and carbohydrate antigen 199(CA199)levels before and after the brachytherapy were recorded.The association between the changes in these parameters and overall survival was analyzed statistically.RESULTS:EUS images of 153 patients with pancreatic cancer and 63 non-cancer patients were analyzed.A total of 25 consecutive patients were enrolled,and they tolerated the brachytherapy well without any complications.There was a correlation between the change in the fuzzy classification score and overall survival(Spearman test,r=0.616,P=0.001),whereas no correlation was found to be significant between the change in tumor volume(P=0.663),CA199 level(P=0.659),and overall survival.There were 15 patients with a decrease in their fuzzy classification score after brachytherapy,whereas the fuzzy classification score increased in another 10 patients.There was a significant difference in overall survival between the two groups(67 d vs 151 d,P=0.001),but not in the change of tumor volume and CA199 level.CONCLUSION:Using the fuzzy classification method to analyze EUS images of pancreatic cancer is feasible,and the method can be used to make prognosis judgments for patients with unresectable pancreatic cancer treated by interstitial brachytherapy.
文摘Background: The aim of breast-conserving treatment (BCT) in breast cancer, consisting of wide local excision (WLE) and radiotherapy, is to obtain local control of disease as well as an optimal cosmetic result. The application of perioperative brachytherapy allows more precise deposition of the boost radiation dose to the lumpectomy cavity plus margins in a shorter period of time, as compared to external beam radiotherapy. The aim of the present study was to analyze the oncological outcome of interstitial brachytherapy in our patient population of patients with early-stage breast cancer. Patients and Methods: 107 breasts in 105 patients with T1-2 breast cancer were treated between 1996 and 2009 with BCT, including WLE combined with perioperative brachytherapy using Iridium-192 (15 Gy with low dose rate or 9 Gy with high dose rate) followed by whole breast irradiation (50 Gy). Outcomes analyzed included treatment toxicity (according to Common Terminology Criteria for Adverse Events), local recurrence rate, and disease-free and overall survival. Results: Median follow-up of patients still alive was 6.3 years (range 2.0 - 14.5). Mean age was 50.2 years (+/- S.D. 10.5). Mean tumor diameter was 15 mm (+/- S.D. 8 mm. Acute complications consisted of grade 1 and 3 complications, respectively n = 8 and n = 1. Late complications consisted of grade 1 or 2, respectively n = 25 and n = 2. Only three patients (2.8%) developed a local recurrence with a median time to recurrence of 9.3 years (range 3.3 - 9.3). Five- and ten-year local recurrence free survival was 99% and 91%, respectively. Five- and ten-year disease-specific and overall survival was 95% and 84% versus 92% and 78%, respectively. Conclusions: Treatment-related toxicity after brachytherapy for breast cancer was mild. The local recurrence rate is low. Therefore, brachytherapy is a good alternative to conventional radiation boost as a part of breast irradiation in breast conserving treatment in early stage breast cancer.
文摘Background: The delivered dose has to be checked and verified with planned dose since precise and accurate dose delivery is essential in Brachytherapy. Sources of uncertainty during Brachytherapy are intra-fraction, inter-fraction and inter-application variations. In-vivo dosimetry is the direct method to monitor the radiation dose delivered to a patient during radiotherapy. In this study, assessment of the inter-fraction and intra-fraction variations in the interstitial Brachytherapy was done with microMOSFET. Aim: To analyze the inter-fraction variations in dose delivery during interstitial HDR Brachytherapy and to compare the measured point dose with the TPS-calculated point dose, intra-fraction variation, using the microMOSFET in-vivo dosimeter. Materials and Methods: From May 2014 to February 2016, 22 patients with Head and Neck cancers and 8 patients with Soft-Tissue Sarcomas (STS) were selected for this study. All these patients underwent CT imaging more than 24 hours after the application. Brachyvision 3DTPS and GammaMed Plus iX HDR unit were used for treatments. MicroMOSFET in-vivo dosimeter after calibration was used for the measurements of dose inside the treated volume. Intra & Inter-fraction variations were analyzed and reported. Results: The SD of inter-fraction variation among 22 Head & Neck patients ranges from 2.14% to 14.26%. Minimum & maximum dose variation with first fraction dose of patients ranged from -22.33% to +26.71% and the mean doses were -6.42% to +19.76%. Differences of TPS dose and microMOSFET measured first fraction dose, intra-fraction variation, ranged from -12.36% to +5.05%. The SD of inter-fraction variation for 8 STS patients was from 2.81% to 14.43%. Minimum and maximum doses vary from -38.72% to +25.74% and mean dose varies from -21.5% to +12.53%. Differences of point doses of TPS and measured, intra-fraction variation, were from -5.86% to 4.88%. Conclusions: MicroMOSFET has the potential to minimize the gross errors during multi-fractionated Interstitial Brachytherapy. Edema, applicator displacements and placement of microMOSFET are the main influencing factors for inter-fraction uncertainty in dose delivery. Re-planning with re-simulated images should be considered whenever the microMOSFET readings vary more than ±10% of the planned dose inside the CTV measured in two successive fractions.
文摘The study was intended to highlight functional outcome and survival advantage when High Dose Rate (HDR) interstitial implant was used for anterior 2/3rd tongue, either as a primary or as boost depending upon stage of disease. Materials and Methods: Fifty-one patients with squamous cell carcinoma of anterior 2/3rd tongue received interstitial brachytherapy either as primary or as boost with Iridium 192 remote after loading high dose rate (Microselectron or Gamma MediX) machines from November 2008 to September 2013. Age group ranged from 32 to 73 years, mean 52.1. Of these 51, 37 were males and 14 were females. 8 patients belonged to Stage I, 18 from Stage II and 28 patients were Stage III. Stage I patients received primary brachytherapy alone of dose 38.50 Gy to 40 Gy and fraction dose ranged from 250 cGy to 350 cGy. Stage II and Stage III patients received external beam radiation of dose 44 Gy/200cGy per fraction for 22 fractions followed by spinal cord sparing for 6 Gy/200cGy per fraction for 3 fractions. Brachytherapy boost of dose 21 Gy was delivered after external beam radiation. Stage III patients received concurrent chemotherapy with Injection Cisplatin along with external beam radiotherapy 44 Gy/200cGy per fraction for 22 fractions followed by spinal cord sparing for 6 Gy/200cGy per fraction for 3 fractions. Brachytherapy boost of dose 21 Gy was delivered after external beam radiation. 55% of patients were habituated to tobacco and alcohol in one form or the other or both. Surprisingly 45% of patients were nonsmokers and non-alcoholic. Results: Follow-up period ranged from eight months to sixty months. 42 patients had complete response. 9 patients had residual disease. 2 patients died due to non-cancerous cause though they had excellent local control, one with pulmonary tuberculosis and the other with massive Myocardial Infarction. 2 patients died due to disease progression. Overall complete response rate was 82.35%. Those patients who had good coverage index and conformal index had good response compared to those patients with lesser these values. Conclusion: It is surprising to observe from the study that oral cavity cancers are not uncommon in non-smokers and non-alcoholics. Overall complete response of 82% is comparable to any other study quoted in literature. Surgery offers same cure rate but at the rate of organ loss and functional impairment. Organ preservation with good functional outcome is possible in radiotherapy unlike surgery. This study proves brachytherapy can be considered as a surrogate to surgery in early stage tongue cancers with good functional outcome and with lesser morbidity.
文摘Background: Patient setup errors in External Beam Radiotherapy (EBRT) are minimized to a great extent, due to recent technological developments but in contrary brachytherapy received least attention in inter-fraction catheter movement and its impact in dose delivery. This article deals with inter-fraction interstitial catheter movement and its impact in dose delivery to the target. An attempt is made to study the dosimetric impact of this variation. Objectives: The objective of the study is to evaluate the inter-fraction variation in the position of implanted interstitial applicators and to assess the dosimetric impact in interstitial High Dose Rate (HDR) brachytherapy. Materials and Methods: 55 patients treated for carcinoma tongue, breast, buccal mucosa, cervix, floor of mouth and soft tissue sarcoma over a period of 2 years (December 2011-May 2013) were considered. All the patients underwent CT scan on the next day of the implant and 3D planning was done either by Eclipse or Oncentra Master plan Treatment Planning System (TPS). Patients were treated by HDR brachytherapy remote after-loading units, either by Gamma Med iX plus or Microselectron. At the end of the last fraction, CT scan was repeated and re-planning done. The variation in position of the implanted applicators/catheters and its impact on dosimetric parameters were evaluated and analyzed. Results: The range of positional displacement of the interstitial catheters ranges from 4.5 mm to 6.8 mm. The maximum variation in prescribed dose to D90 of Clinical Target Volume was 10.88%. Conclusions: If the total duration of interstitial implant of HDR brachytherapy extends for more than a week from the day of imaging, it is recommended to do CT imaging and re-plan again. It is mandatory to suture the buttons of the implant to the skin. Edema and movement of organs (e.g., tongue) are the main cause for the positional variation of the catheters.
文摘Objective:The aim of our study was to explore the influence of interstitial brachytherapy with 125I seeds on Caspase-3 and Egr-1 expressions of Lewis lung carcinoma in C57BL mice.Methods:Model mice of C57BL were planted with Lewis lung cells (LLC) and divided into the treatment group (n=18) and the control group (n=17).In each mouse of the treatment group,two BT-125-1 Model 125I seeds with apparent activity of 9.25 MBq were implanted into the tumor;whereas in each mouse of the control group two dummy seeds were implanted.The mice survival rates of both groups were recorded after 21 days.The tumor weights and dimensions of survived mice were measured,and the tumor volume inhibition rate was calculated.T-test was performed to compare differences of tumor weights and volumes between these two groups.Routine pathological slides of tumor tissue were observed under light microscope.The expression of Caspase-3 was detected by immunohistochemical method and the expression of Egr-1 was detected by RT-PCR method.Results:The survival rates were 88.88% in the treatment group and 70.59% in the control group,the difference had no statistical significance (P > 0.05).The tumor volume inhibition rate was 71.12%.Pathological examination showed degeneration and necrosis of cancer cells at the site nearby the seed in the treated group,but the tumor cells alive were still presented nearby the seed in the control group.The expressions of Caspase-3 and Egr-1 in the treated group were higher than those in the control group (t=12.825,P < 0.01;t=7.039,P < 0.01;respectively).Conclusion:The interstitial brachytherapy with 125I seeds could significantly inhibit the growth of Lewis lung carcinoma of mice.The possible mechanism may be that 125I interstitial brachytherapy can enhance the expressions of Egr-1 and Caspase-3,which could induce tumor cellular apoptosis.
文摘Background: Treatment of Cervical cancer includes a combination of external beam radiotherapy (EBRT) with intracavitary brachytherapy (ICBT). ICBT helps to boost radiation dose to primary disease. Organs like rectum, bladder, sigmoid and small bowel lie close to the cervix region and these organs receive dose from EBRT as well as ICBT and we want to know the dose to these organ at risk (OAR). Materials & Methods: Dosimetric details of 174 ICBT applications done in 58 patients were retrospectively analysed. All patients received EBRT dose of 50.4 Gy in 28 fractions. All patients had ICBT, three sessions with 7 Gy prescribed to point A. Dosimetric data including dose to right and left point A and dose to OARs were recorded from Oncentra Planning System. Results: Mean dose to point A on right side was 6.89 Gy and left side was 6.91 Gy. Mean D2cc dose to rectum, bladder, sigmoid and small bowel was 3.5 Gy, 5.25 Gy, 4.75 Gy and 4.2 Gy respectively. Mean EQD2 dose combining EBRT and ICBT in point A was 78.7 Gy on right side and 79 Gy on left side. Mean EQD2 doses to D2cc of rectum, bladder, sigmoid and small bowel was 62 Gy, 74.4 Gy, 70.5 Gy and 66.5 Gy respectively. Conclusion: From the results of this dosimetric study it is evident that OARs like rectum, sigmoid, bladder & bowel are receiving only acceptable doses of radiation using point A prescribed CT based ICBT planning. Hence with regards to OAR doses, CT based ICBT planning with dose prescribed to point A is a feasible option.
文摘Purpose: Curative radiation therapy is an established treatment option for non-surgical patients with early-stage endometrial carcinoma. Dosimetric analyses were performed using a single tandem, double tandem, Heyman capsules, and an inflatable intrauterine balloon to assess the dose homogeneity and conformality in the definitive treatment of inoperable endometrial cancer. Methods and Materials: Patients’ informed-consent was obtained. Dosimetric analyses were performed using four different after-loading applicators to assess the dose homogeneity and conformality of isodose to the three-dimensional (3-D) shape of the target volume (uterus) based on CT data in four patients (n = 4). The single tandem and double tandems were standard Fletcher-type (Nucletron Corporation, Columbia, MD). Heyman capsules were the disposable after-loading type (Radiation Products Design, Inc., Albertville, MN). The inflatable balloon with a central bi-lumen catheter was the Mammo Site Radiation Therapy System (Proxima Therapeutics, Alpharetta, GA) that is currently used for local breast brachytherapy. Treatment planning and dosimetric analyses for all four techniques were done with HDR PLATO Brachytherapy (v14.2.3) Software (Nucletron Corporation). Results: The average dose gradient within the target (uterine wall) is highest with the tandem methods, followed by Heyman capsules. The intrauterine balloon method showed the least dose gradient across the uterine wall. The corresponding average homogeneity indices were 3.81, 3.83, 2.97, 2.50 for single tandem, double tandem, Heyman capsules, and intrauterine balloon respectively. Conclusions: The intra-uterine inflatable balloon appears to have the best overall dosimetric advantages for the treatment of the uterine wall. Furthermore, the potential ease of use, shorter time of applicator placement, and better patient comfort warrant further investigation and subsequent clinical implementation.
文摘Objective:To observe the effects of Methyl Carboprost and Diclofenac Sodium on opening orifice of uterus and pain controlling in patients with uterine cervix cancer (UCC) when receiving intracavitary brachytherapy. Methods: Sixty patients with UCC of stage IIA-IIIB were divided into three groups randomly before receiving the intracavitary brachytherapy: the patients in group A received Methyl Carboprost in the hind fornix of the vagina, group B received Diclofenac Sodium in the anus, while group C was the control group. Results: The painlessness rates in groups A, B and C were 89.9%, 91.3% and 36.4%, respectively. The incidences of patients with relaxed uterus cervix in groups A, B and C were 91.7%, 85.9% and 48.9%, respectively. Conclusion: Methyl Carboprost and Diclofenac Sodium are useful in relaxing uterus cervix and pain controlling in patients with UCC when receiving intracavitary brachytherapy.
文摘Objective: The aim of our study was to evaluate the outcome and complications of cervical cancer patients undergoing conventional intracavitary brachytherapy (ICBT) treated with 3D-conformal radiotherapy (3DCRT). Methods: Sixty cervical cancer patients were divided randomly into the conformal group and the conventional group. Thirty patients treated with 3D-conformal radiotherapy in the 3DCRT group, when the whole pelvic received DT 40 Gy, a planning CT scan of each patient was obtained and the second 3DCRT therapy plan was taken. Then, continued to irradiate to 50 Gy. At last, 3DCRT was boosted at local involved volumes to the total dose of 60 Gy. When 3DCRT was combined with intracavitary brachytherapy, the dose of brachytherapy to point A was 30 Gy/5 fractions. In the conventional group, after a total tumor dose of 40 Gy was delivered by the whole pelvic irradiation, the four-field technique was used to irradiate the total pelvic and regional nodes (median dose of 10 Gy), and the involved volumes were boosted to 60 Gy and the dose of brachytherapy to point A was 30 Gy-36 Gy/5-6 fractions. Moreover, both groups were combined with intracavitary brachytherapy respectively. Results: The 1, 2, 3-year survival rates for the 3DCRT group and the conventional group were 96.7%, 93.3%, 90.0% and 86.6%, 76.7%, 70% respectively (P = 0.04, P = 0.02 and P = 0.02). There was a statistically significant difference between the two groups. Compared to the two groups each other in toxic effects, except for the I-II grade rectal and bladder reaction and pelvic fibrosis which was lower in the 3DCRT group (P = 0. 007, P = 0. 006 and P = 0. 015), the side effects were similar and well tolerated in two groups. Conclusion: The all-course 3DCRT combined with intracavitary brachytherapy can be considered as an effective and feasible approach to cervical cancer and may significantly improve the survival rate and reduce the late toxicity. This new role for 3DCRT merits need further evaluation with large patient numbers and longer follows up.
文摘OBJECTIVE To evaluate the results and complications associated with nasopharyngeal carcinoma (NPC) treated with combined external-beam radiotherapy (EBR) and intracavitary brachytherapy (IB) using a new-type applicator. METHODS Eighty patients with untreated NPC were divided into two groups based on therapy methods. An experimental group was treated with EBR plus IB and a control group was treated only with EBR. IB was given to the patients of the experimental group when the external radiotherapy dose amounted to more than 60~65 Gy. The total dose of IB was 6~20 Gy and the total dose of EBR of the control group was 70~75 Gy. RESULTS Follow-up was conducted for 97.5% of the patients with re- suits as follows: the overall response rates (ORR) for the experimental and the control groups were 92.5% and 75.3% respectively (P〈0.05); the 3 and 5-year survival rates for the experimental group were 87.5% and 74.2% and for the control group, 65.0% and 55.6% (P〈0.05); for the experimental group, the 3 and 5-year disease-free survival rates were 72.5% and 64.5% and for the control group, 60.0% and 52.8% (P〉0.05).Some complications following radiotherapy showed a significant difference. CONCLUSION External irradiation plus intracavitary brachytherapy using a new-type applicator may improve the ORR and survival rates, reduce radiation complications and increase the quality of life.
文摘Brachytherapy forms an integral part of the radiation therapy in cancer cervix. The dose prescription for intracavitary brachytherapy(ICBT) in cancer cervix is based on Tod and Meredith's point A and has been in practice since 1938. This was proposed at a time when accessibility to imaging technology and dose computation facilities was limited. The concept has been in practice worldwide for more than half a century and has been the fulcrum of all ICBT treatments, strategies and outcome measures. The method is simple and can be adapted by all centres practicing ICBT in cancer cervix. However, with the widespread availability of imaging techniques, clinical use of different dose-rates, availability of a host of applicators fabricated with image compatible materials, radiobiological implications of dose equivalence and its impact on tumour and organs at risk; more and more weight is being laid down on individualised image based brachytherapy. Thus, computed tomography, magnetic-resonance imaging and even positron emission computerized tomographyalong with brachytherapy treatment planning system are being increasingly adopted with promising outcomes. The present article reviews the evolution of dose prescription concepts in ICBT in cancer cervix and brings forward the need for image based brachytherapy to evaluate clinical outcomes. As is evident, a gradual transition from "point" based brachytherapy to "profile" based image guided brachytherapy is gaining widespread acceptance for dose prescription, reporting and outcome evaluation in the clinical practice of ICBT in cancer cervix.