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
Early stage cancers of tongue are treated traditionally with a wide local excision or hemiglossectomy, but the preservation of normal speech and swallowing are hampered. Most of the patients are treated with external ...Early stage cancers of tongue are treated traditionally with a wide local excision or hemiglossectomy, but the preservation of normal speech and swallowing are hampered. Most of the patients are treated with external beam irradiation to achieve the best locoregional control as only a limited number of tongue cancers can be excised. Underdeveloped nations with finite resources are still dependent on cobalt based external beam radiotherapy and sometimes a Linear Accelerator with two dimensional planning. This treatment has many limitations, as the large radiation fields irradiate not only the tumor but also normal tissue. The sequalae include mucositis, dry mouth, teeth and gum injury, spinal cord damage and rarely mandibular necrosis. Intensity modulated radiotherapy, which can abrogate these side effects, is not available to these patients. Irradiation using implanted solid radioactive sources into the tumor tissue is a viable option in this context. This kind of treatment is termed as brachytherapy and if the implant is introduced into the tissue then it is interstitial brachytherapy. This report details our experience in interstitial implantation, planning, dosimetry and treatment. Diagnosed cancers of anterior 2/3rd of lateral border of tongue with T1 N0M0 or T2 N0M0 stages were subjected to Iridium implantation under general anesthesia. Orthogonal films were taken and planning done with brachyvision treatment planning system. High dose rate radiotherapy was delivered as per the prescription. Excellent local control of the tumor was achieved with no undue morbidity to the adjacent structures. The patients were asked to undergo regular follow up. Surgical salvage was advised in cases of nodal recurrence. Interstitial implantation is a treatment that can be safely administered in early stage cancers of the tongue. This has remarkable efficacy and is also a patient friendly procedure.展开更多
目的探讨CT引导放射性125I植入治疗纵隔淋巴结转移瘤的方法、安全性和临床疗效。方法对11例纵隔淋巴结转移瘤患者行CT引导下放射性125I粒子植入治疗,术前采用近距离治疗计划系统(TPS)制定计划,选择粒子活度:(1.11~2.96)×107Bq(0.3~...目的探讨CT引导放射性125I植入治疗纵隔淋巴结转移瘤的方法、安全性和临床疗效。方法对11例纵隔淋巴结转移瘤患者行CT引导下放射性125I粒子植入治疗,术前采用近距离治疗计划系统(TPS)制定计划,选择粒子活度:(1.11~2.96)×107Bq(0.3~0.8 m Ci),术后观察并发症发生情况,术后1、3、6、12个月评价肿瘤局部控制率、疼痛缓解有效率。结果术后出现气胸3例,气管瘘1例,肺部感染1例。随访1、3、6、12个月,患者局部控制率为81.8%、90.9%、72.7%、72.7%;疼痛缓解有效率,1周100%、1个月90.9%、3个月90.9%、6个月81.8%、12个月72.7%。结论 CT引导放射性125I粒子植入治疗纵隔转移瘤创伤小、并发症少、局部病灶控制率确切,是一种较为安全的治疗方法。展开更多
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Early stage cancers of tongue are treated traditionally with a wide local excision or hemiglossectomy, but the preservation of normal speech and swallowing are hampered. Most of the patients are treated with external beam irradiation to achieve the best locoregional control as only a limited number of tongue cancers can be excised. Underdeveloped nations with finite resources are still dependent on cobalt based external beam radiotherapy and sometimes a Linear Accelerator with two dimensional planning. This treatment has many limitations, as the large radiation fields irradiate not only the tumor but also normal tissue. The sequalae include mucositis, dry mouth, teeth and gum injury, spinal cord damage and rarely mandibular necrosis. Intensity modulated radiotherapy, which can abrogate these side effects, is not available to these patients. Irradiation using implanted solid radioactive sources into the tumor tissue is a viable option in this context. This kind of treatment is termed as brachytherapy and if the implant is introduced into the tissue then it is interstitial brachytherapy. This report details our experience in interstitial implantation, planning, dosimetry and treatment. Diagnosed cancers of anterior 2/3rd of lateral border of tongue with T1 N0M0 or T2 N0M0 stages were subjected to Iridium implantation under general anesthesia. Orthogonal films were taken and planning done with brachyvision treatment planning system. High dose rate radiotherapy was delivered as per the prescription. Excellent local control of the tumor was achieved with no undue morbidity to the adjacent structures. The patients were asked to undergo regular follow up. Surgical salvage was advised in cases of nodal recurrence. Interstitial implantation is a treatment that can be safely administered in early stage cancers of the tongue. This has remarkable efficacy and is also a patient friendly procedure.
文摘目的探讨CT引导放射性125I植入治疗纵隔淋巴结转移瘤的方法、安全性和临床疗效。方法对11例纵隔淋巴结转移瘤患者行CT引导下放射性125I粒子植入治疗,术前采用近距离治疗计划系统(TPS)制定计划,选择粒子活度:(1.11~2.96)×107Bq(0.3~0.8 m Ci),术后观察并发症发生情况,术后1、3、6、12个月评价肿瘤局部控制率、疼痛缓解有效率。结果术后出现气胸3例,气管瘘1例,肺部感染1例。随访1、3、6、12个月,患者局部控制率为81.8%、90.9%、72.7%、72.7%;疼痛缓解有效率,1周100%、1个月90.9%、3个月90.9%、6个月81.8%、12个月72.7%。结论 CT引导放射性125I粒子植入治疗纵隔转移瘤创伤小、并发症少、局部病灶控制率确切,是一种较为安全的治疗方法。
