Introduction: Radiation therapy after breast surgery is an integral part of the treatment of early breast cancer. The goal of radiation therapy is to achieve the best possible coverage of the planning target volume (P...Introduction: Radiation therapy after breast surgery is an integral part of the treatment of early breast cancer. The goal of radiation therapy is to achieve the best possible coverage of the planning target volume (PTV), while reducing the dose to organs at risk (OARs) which are normal tissues whose sensitivity to irradiation could cause damage that can lead to modification of the treatment plan. In the last decade, radiation oncologist started to use the Intensity Modulated Radiotherapy (IMRT) and Volumetric Modulated Arc Therapy (VMAT) for irradiating the breast, in order to achieve better dose distribution and target dose to the PTV and OAR. The aim of this study is to compare 2 external radiotherapy techniques (VMAT vs 3D) for patients with node-positive left breast cancer. Patients and Methods: We randomly selected 10 cases of postoperative radiotherapy for breast cancer in our hospital. The patients are all female, the average age was 45.4 years old, and the primary lesions are left breast. The ANOVA test was used to compare the mean difference between subgroups, and the p value Results: Dose volume histogram (DVH) was used to analyze each evaluation dose of clinical target volume (CTV) and organs at risk (OARs). Compared to 3DCRT plans, VMAT provided more uniform coverage to the breast and regional lymph nodes. The max point dose for tVMAT was lower on average (106.4% for VMAT versus 109% for 3DCRT). OAR sparing was improved with tVMAT, with a lower average V17Gy for the left lung (27.91% for VMAT versus 30.04% for 3DCRT, p and lower for V28Gy (13.75% for VMAT versus 22.34% for 3DCRT, p = 0.01). We also found a lower V35Gy for the heart on VMAT plan (p = 0.02). On the contrary, dose of contralateral breast was lower in 3DCRT than VMAT (0.59 Gy vs 3.65 Gy, p = 0.00). Conclusion: The both types of plans can meet the clinical dosimetry demands of postoperative radiotherapy for left breast cancer. The VMAT plan has a better conformity, but 3CDRT can provide a lower dose to the contralateral organs (breast and lung) to avoid the risk of secondary cancers.展开更多
Background: Radiation therapy should not only be directed to improve the local control, which has a survival benefit, but also should be directed to minimize the risk of complications, which may develop in critical or...Background: Radiation therapy should not only be directed to improve the local control, which has a survival benefit, but also should be directed to minimize the risk of complications, which may develop in critical organs. Several studies have reported that field-in-field (FiF) radiotherapy technique improves the dose homogeneity, decreases doses to lungs, heart and contralateral breast compared with conventional wedged technique. Purpose: compare the dosimetry for the left breast cancer radiotherapy using three different radiotherapy techniques, tangential wedged fields (TW), segmented field (FiF) and inverse planning IMRT (IP-IMRT). Material and Methods: Twenty patients have undergone left breast-conservative surgery and received a prescribed dose of 50 Gy/25 fractions. Results: The mean PTV receiving >105% (V105) dose was1.75% for IP-IMRT, 2.03% for FiF, and 4.82% for TW. The mean V95% was 92.1% for TW, 96% for FiF, and 95.1% for IP-IMRT;these differences regarding V105% and V95% are statistically significant through paired comparison between FiF vs TW and IP-IMRT vs TW, with no statistically significant difference between FiF and IP-IMRT. Better conformity and homogeneity indices for FiF and IMRT compared to TW with statistical significant difference. Regarding organs at risk, left lung and heart have higher values of V5, V10, and V20 for IP-IMRT compared to TW and FiF;the differences are statistically significant, lower coronary artery regionV30 vules for IPIMRT compared to TW and FiF but no difference in the Dmean between IPIMRT and FIF. FiF and TW decrease the contralateral breast dose significantly compared to IP IMRT. Conclusion: FiF technique is an efficient and reliable method for achieving a uniform dose throughout the whole breast resulting in improved coverage, sparing of organs at risk and reduction of acute and late toxicities.展开更多
Background: Cardiac toxicity is currently defined as a symptomatic decrease in Left Ventricular Ejection Fraction (LVEF) of more than 5% or an asymptomatic decrease of at least 10% to a value of under 50% in repeated ...Background: Cardiac toxicity is currently defined as a symptomatic decrease in Left Ventricular Ejection Fraction (LVEF) of more than 5% or an asymptomatic decrease of at least 10% to a value of under 50% in repeated evaluations on conventional transthoracic echocardiogram (TTE), as well as a Global Longitudinal Strain (GLS) value Aims: To highlight using GLS rather than modified Simpson 2D-LVEF for the evaluation of long-term cardiotoxicity. Case Presentation: The case concerns a 73-year-old female patient with a history of breast cancer chemotherapy and anthracyclines-based therapy who presented symptoms of late cardiac toxicity related to the chemotherapeutic treatment. In the following years, the patient remained asymptomatic with a 2D-LVEF of 48%, dilation of the left atrium was found, and the reservoir phase strain was severely decreased. Conclusion: The preferred method for evaluating cardiovascular complications associated with chemotherapy is the TTE, which is performed prior to the start of treatment, during therapy, and in the follow-up. Myocardial deformation as a predictor of cardiotoxicity allows the identification of subclinical heart failure.展开更多
目的:探讨体质量指数(body mass index,BMI)对乳腺癌患者治疗中位移误差的影响,为乳腺癌放射治疗中计划靶区外放边界提供数据支持。方法:回顾性分析本中心乳腺癌治疗的患者153例,利用CBCT获取摆位误差,并对数据进行挖掘,计算出两组因BM...目的:探讨体质量指数(body mass index,BMI)对乳腺癌患者治疗中位移误差的影响,为乳腺癌放射治疗中计划靶区外放边界提供数据支持。方法:回顾性分析本中心乳腺癌治疗的患者153例,利用CBCT获取摆位误差,并对数据进行挖掘,计算出两组因BMI的不同而导致的误差和PTV外放的差别。结果:从左乳和右乳的摆位误差分析计算得出:在考虑BMI情况下,左乳在腹背Z方向的摆位误差随BMI的增大而略有增大。右乳在Rx方向的摆位误差随BMI的增大而增大。左乳中,腹背Z方向外扩边界随BMI增大而逐渐增大。右乳中,头脚Y方向外扩边界随BMI增大而增大。结论:医师可根据乳腺癌的左右位置和BMI的大小来判断Mptv的扩大或者缩小,从而为患者提供更个性化精准化治疗。展开更多
文摘Introduction: Radiation therapy after breast surgery is an integral part of the treatment of early breast cancer. The goal of radiation therapy is to achieve the best possible coverage of the planning target volume (PTV), while reducing the dose to organs at risk (OARs) which are normal tissues whose sensitivity to irradiation could cause damage that can lead to modification of the treatment plan. In the last decade, radiation oncologist started to use the Intensity Modulated Radiotherapy (IMRT) and Volumetric Modulated Arc Therapy (VMAT) for irradiating the breast, in order to achieve better dose distribution and target dose to the PTV and OAR. The aim of this study is to compare 2 external radiotherapy techniques (VMAT vs 3D) for patients with node-positive left breast cancer. Patients and Methods: We randomly selected 10 cases of postoperative radiotherapy for breast cancer in our hospital. The patients are all female, the average age was 45.4 years old, and the primary lesions are left breast. The ANOVA test was used to compare the mean difference between subgroups, and the p value Results: Dose volume histogram (DVH) was used to analyze each evaluation dose of clinical target volume (CTV) and organs at risk (OARs). Compared to 3DCRT plans, VMAT provided more uniform coverage to the breast and regional lymph nodes. The max point dose for tVMAT was lower on average (106.4% for VMAT versus 109% for 3DCRT). OAR sparing was improved with tVMAT, with a lower average V17Gy for the left lung (27.91% for VMAT versus 30.04% for 3DCRT, p and lower for V28Gy (13.75% for VMAT versus 22.34% for 3DCRT, p = 0.01). We also found a lower V35Gy for the heart on VMAT plan (p = 0.02). On the contrary, dose of contralateral breast was lower in 3DCRT than VMAT (0.59 Gy vs 3.65 Gy, p = 0.00). Conclusion: The both types of plans can meet the clinical dosimetry demands of postoperative radiotherapy for left breast cancer. The VMAT plan has a better conformity, but 3CDRT can provide a lower dose to the contralateral organs (breast and lung) to avoid the risk of secondary cancers.
文摘Background: Radiation therapy should not only be directed to improve the local control, which has a survival benefit, but also should be directed to minimize the risk of complications, which may develop in critical organs. Several studies have reported that field-in-field (FiF) radiotherapy technique improves the dose homogeneity, decreases doses to lungs, heart and contralateral breast compared with conventional wedged technique. Purpose: compare the dosimetry for the left breast cancer radiotherapy using three different radiotherapy techniques, tangential wedged fields (TW), segmented field (FiF) and inverse planning IMRT (IP-IMRT). Material and Methods: Twenty patients have undergone left breast-conservative surgery and received a prescribed dose of 50 Gy/25 fractions. Results: The mean PTV receiving >105% (V105) dose was1.75% for IP-IMRT, 2.03% for FiF, and 4.82% for TW. The mean V95% was 92.1% for TW, 96% for FiF, and 95.1% for IP-IMRT;these differences regarding V105% and V95% are statistically significant through paired comparison between FiF vs TW and IP-IMRT vs TW, with no statistically significant difference between FiF and IP-IMRT. Better conformity and homogeneity indices for FiF and IMRT compared to TW with statistical significant difference. Regarding organs at risk, left lung and heart have higher values of V5, V10, and V20 for IP-IMRT compared to TW and FiF;the differences are statistically significant, lower coronary artery regionV30 vules for IPIMRT compared to TW and FiF but no difference in the Dmean between IPIMRT and FIF. FiF and TW decrease the contralateral breast dose significantly compared to IP IMRT. Conclusion: FiF technique is an efficient and reliable method for achieving a uniform dose throughout the whole breast resulting in improved coverage, sparing of organs at risk and reduction of acute and late toxicities.
文摘Background: Cardiac toxicity is currently defined as a symptomatic decrease in Left Ventricular Ejection Fraction (LVEF) of more than 5% or an asymptomatic decrease of at least 10% to a value of under 50% in repeated evaluations on conventional transthoracic echocardiogram (TTE), as well as a Global Longitudinal Strain (GLS) value Aims: To highlight using GLS rather than modified Simpson 2D-LVEF for the evaluation of long-term cardiotoxicity. Case Presentation: The case concerns a 73-year-old female patient with a history of breast cancer chemotherapy and anthracyclines-based therapy who presented symptoms of late cardiac toxicity related to the chemotherapeutic treatment. In the following years, the patient remained asymptomatic with a 2D-LVEF of 48%, dilation of the left atrium was found, and the reservoir phase strain was severely decreased. Conclusion: The preferred method for evaluating cardiovascular complications associated with chemotherapy is the TTE, which is performed prior to the start of treatment, during therapy, and in the follow-up. Myocardial deformation as a predictor of cardiotoxicity allows the identification of subclinical heart failure.
文摘目的:探究左侧乳腺癌保乳术后基于内缘切线拉弧的容积调强放疗(volumetric modulated arc therapy,VMAT)与常规切线拉弧的VMAT的剂量学差异,挖掘VMAT技术在乳腺癌保乳术后更大的获益,为乳腺癌保乳术后VMAT计划设计提供更多的参考和数据支持。方法:回顾性选取30例左侧乳腺癌保乳术后行调强放疗的患者,为每位患者分别设计常规切线拉弧(conventional tangential arc,CTA)和内缘切线拉弧(inner edge tangentialarc,IETA)两组VMAT计划。统计两组计划的靶区适形度指数(conformity index,CI)、均匀性指数(homogeneity index,HI)、机器跳数、危及器官受照剂量等数据,并进行数据分析。结果:靶区适形性指数(CI)CTA组和IETA组分别为0.86±0.02和0.87±0.02(P<0.05),D_(98)、D_(50)、D_(2)、均匀性指数(HI)和机器跳数均无明显差异(P>0.05);IETA组危及器官左肺V_(5)、V_(10)、V_(20)、V_(30)、V_(40)、D_(mean),右肺V_(5)、D_(mean),心脏V_(5)、V_(10)、V_(20)、D_(mean)均低于CTA组(P<0.05),其中左肺V_(5)和V_(20)CTA组和IETA组分别为37.18±7.18 vs 34.32±6.43、11.00±2.40 vs 9.65±2.17;右肺D_(mean)和心脏D_(mean)CTA组和IETA组分别为302.26±42.78 vs 273.50±26.62,479.30±60.08 vs 442.39±140.92,IETA组均低于CTA组;两组右侧乳腺D_(mean)相差甚微(P>0.05)。结论:两种计划均能满足临床要求,但IETA的VMAT靶区适形度明显提高,同时还显著降低了左肺、右肺、心脏和脊髓的受量。因此,左侧乳腺癌保乳术后基于内缘切线拉弧VMAT可实现靶区和危及器官更大的获益,值得推荐。
文摘目的:探讨体质量指数(body mass index,BMI)对乳腺癌患者治疗中位移误差的影响,为乳腺癌放射治疗中计划靶区外放边界提供数据支持。方法:回顾性分析本中心乳腺癌治疗的患者153例,利用CBCT获取摆位误差,并对数据进行挖掘,计算出两组因BMI的不同而导致的误差和PTV外放的差别。结果:从左乳和右乳的摆位误差分析计算得出:在考虑BMI情况下,左乳在腹背Z方向的摆位误差随BMI的增大而略有增大。右乳在Rx方向的摆位误差随BMI的增大而增大。左乳中,腹背Z方向外扩边界随BMI增大而逐渐增大。右乳中,头脚Y方向外扩边界随BMI增大而增大。结论:医师可根据乳腺癌的左右位置和BMI的大小来判断Mptv的扩大或者缩小,从而为患者提供更个性化精准化治疗。
