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Cardiotoxicity caused by postoperative radiotherapy can increase the risk of cardiovascular adverse events in patients with breast cancer, especially those with left breast cancer, which is proportional to the dose of radiation to the heart. It has been proved that deep inspiration breath-hold (DIBH) technique can significantly reduce the cardiac dose in patients with left breast cancer, but the benefits of this technique vary greatly among different patients, and its implementation requires additional equipment, time, manpower and other resources. Hence, it is necessary to select patients who are suitable for this technique in advance. In addition to comprehensive analysis of general factors before simulation positioning that affect DIBH selection, this review also systematically summarized relevant indicators of CT simulation positioning images. These anatomical indicators included the measurement of the cardiac contact distances in parasagittal (CCD ps) plane, the lateral heart-to-chest distance (HCD), the product of maximum heart width (HW max) and the maximum heart depth (HD max) during CT simulation positioning, and the maximum heart distance, heart volume in the irradiation field (HVIF), the difference of lung volume and heart volume between free breathing (FB) and DIBH measured after CT localization. All of them showed some instructive significance for evaluating whether DIBH should be applied in tangent field based radiotherapy planning. The automatic planning (rapid plan) function in the treatment planning system could quickly predict the benefit of DIBH for breast cancer patients. The purpose of this article is to help clinicians select patients who are suitable for DIBH technique, guaranteeing that DIBH technique resources can be used reasonably.
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Surface guided radiation therapy (SGRT) is a method of radiation therapy with non-invasive and non-radiation image guidance technology, which uses continuous real-time imaging to monitor the whole course of treatment. This paper summarizes the characteristics, representative products, application in clinical research and treatment, and quality control of SGRT. This emerging technology plays an increasingly important role in delivering more precise, safe, and comfortable radiotherapy to patients.
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PURPOSE: To observe the effectiveness of the practical instruction sheet and the educational video for left-sided breast treatment in a patient receiving deep inspiration breath hold (DIBH) technique. Two parameters, simulation time and patient satisfaction, were assessed through the questionnaire. METHODS: Two different approaches, which were the instruction sheet and educational video, were combinedly used to assist patients during DIBH procedures. The guideline was assigned at least 1 week before the simulation date. On the simulation day, patients would fill the questionnaire regarding their satisfaction with the DIBH instruction. The questionnaire was categorized into five levels: extremely satisfied to dissatisfied, sequentially. The patients were divided into four groups: not DIBH technique, DIBH without instruction materials, the DIBH with instruction sheet or educational video, and DIBH with both of instruction sheet and educational video. RESULTS: Total number of 112 cases of left-sided breast cancer were analyzed. The simulation time during DIBH procedure significantly reduced when patients followed the instruction. There was no significant difference in simulation time on the DIBH procedures between patient compliance via instruction sheet or educational video or even following both of them. The excellent level was found at 4.6 ± 0.1 and 4.5 ± 0.1, for patients coaching via instruction sheet as well as on the educational video, respectively. CONCLUSION: Patient coaching before simulation could potentially reduce the lengthy time in the simulation process for DIBH technique. Practicing the DIBH technique before treatment is strongly advised.
Subject(s)
Humans , Breast Neoplasms , Breast , Cardiotoxicity , Patient Compliance , Patient Satisfaction , Unilateral Breast NeoplasmsABSTRACT
In radiotherapy for thoracic and abdominal tumors, the negative effect of respiratory movement on radiotherapy persist throughout the whole process of radiotherapy. Deep inspiration breath-hold technique (DIBH) is a method of respiratory movement management in radiotherapy, which can reduce the negative effect of respiratory movement upon radiotherapy in the whole process of radiotherapy. Meantime, DIBH technique has its own characteristics and operation requirements compared with other respiratory movement management measures (such as 4D CT, gated technology and tracking, etc.). The aim of this review was to introduce the advantages, disadvantages and the application status of DIBH technique.
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PURPOSE: Deep inspiration breath hold (DIBH) is a well-established technique that enables efficient cardiac sparing in patients with left-sided breast cancer. The aim of the current study was to determine if DIBH is effective for reducing radiation exposure of of liver and other organs at risk in right breast radiotherapy (RT).MATERIALS AND METHODS: Twenty patients with right-sided breast cancer were enrolled in this study. Three-dimensional conformal RT plans were generated for each patient, with two different computed tomography scans of free breathing (FB) and DIBH. Nodes were contoured according to the Radiation Therapy Oncology Group contouring guidelines. Dose-volume histograms for the target volume coverage and organs at risk were evaluated and analyzed.RESULTS: DIBH plans showed significant reduction in mean liver dose (5.59 ± 2.07 Gy vs. 2.54 ± 1.40 Gy; p = 0.0003), V(20Gy) (148.38 ± 73.05 vs. 64.19 ± 51.07 mL; p = 0.0003) and V(10Gy) (195.34 ± 93.57 vs. 89.81 ± 57.28 mL; p = 0.0003) volumes compared with FB plans. Right lung doses were also significantly reduced in DIBH plans. Heart and left lung doses showed small but statistically significant improvement with application of the DIBH technique.CONCLUSION: We report that the use of DIBH for right-sided breast cancer significantly reduces the radiation doses to the liver, lungs, and heart.
Subject(s)
Humans , Breast Neoplasms , Breast , Heart , Liver , Lung , Organs at Risk , Radiation Exposure , Radiotherapy , Respiration , Unilateral Breast NeoplasmsABSTRACT
Objective To analyze the correlation between treatment time and radiotherapy plan of deep inspiration breath-hold (DIBH) technique for the whole breast irradiation (WBI) in the left breast cancer after breast-conserving surgery,verify the inter-fractional reproducibility of radiotherapy,observe the heart location and dosimetric changes and calculate the effect of DIBH upon the WBI setup error after the surgery.Methods We prospectively enrolled 15 patients with left breast cancer undergoing WBI after breast-conserving surgery,who met the requirement of D1BH.Treatment time was recorded,its correlation with the number of field and monitor unit was analyzed.Inter-fractional setup errors and PTV delineation were calculated using cone beam CT (CBCT).The accuracy of the position and dose of the heart during radiotherapy was verified by the imaging fusion of CBCT and CT images.The variables among groups were analyzed by non-parametric Firedman test.Results The average treatment time of DIBH radiotherapy was 4.6 minutes.The treatment time was correlated with the maximal and total number of sub-fields and total monitor units.During DIBH treatment,the mean cardiac displacement volume was 19.1 cm3(3.8％).The mean cardiac dose difference between CBCT and planning CT was 5.1 cGy,and there was no significant difference in the heart V5-V30.The mean inter-fractional system setup error (∑) and random setup error (σ) in the left-right (x),superior-inferior (y) and anterior-posterior (z) direction were ∑x 1.9 mm,∑y 2.1 mm,∑z 2.0 mm,σx 1.3 mm,σy 1.3 mm,σz 1.4 mm,respectively.The corresponding minimal margins for setup error were 5.7 mm,6.2 mm and 6.0 mm,respectively.Conclusion DIBH for WBI after breast-conserving surgery does not significantly prolong the treatment time.Treatment time is related to treatment plan.DIBH yields high inter-fractional reproducibility and protects the heart.
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Objective To study the effect of deep inspiration breath-hold(DIBH)technique on the heart dose in whole breast irradiation(WBI)for left breast cancer after breast-conserving surgery, and to investigate the anatomical factors for heart dose. Methods Fifteen patients with left breast cancer who received WBI after breast-conserving surgery and met breathing control requirements were prospectively enrolled as subjects. Simulated CT scans were performed during free breathing(FB)and DIBH. The WBI plans were optimized based on DIBH images.The position,volume,and radiation doses to the heart and lung were compared between the status of FB and DIBH. Correlation of heart dose with various anatomical factors was analyzed in FB status. Between-group comparison of categorical data was made by nonparametric Wilcoxon rank test.A two-variable correlation analysis was made by the Pearson method.Results There was no significant difference in heart volume between the status of FB and DIBH(P=0.773).The volume of both lungs was significantly larger in DIBH status than in FB status(P=0.001). The mean and maximum doses and V5-V40for the heart,left anterior descending coronary artery,left ventricle,right ventricle,and left lung were significantly lower in DIBH status than in FB status(all P<0.05). The greater DIBH increased the lung volume,the greater the mean heart dose decreased. In FB status,the left breast volume,heart-to-lung volume ratio,distance between the inferior margins of breast and heart,and maximum heart margin distance showed a linear correlation with heart dose. Particularly, the heart-to-lung volume ratio and maximum heart margin distance were independently correlated with heart dose. Conclusions DIBH technique in WBI for left breast cancer after breast-conserving surgery significantly reduces heart and lung doses compared with FB. Changes in lung volume are the basis for improving the relative anatomical location of the heart. The heart-to-lung volume ratio and maximum heart margin distance may provide a reference for DIBH technique.
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Objective Objective To evaluate the effect of deep inspiration breath-hold technique (DIBH) on the dosimetry of target volume and organs at risk (OARs) in mediastinal lymphoma irradiation.Methods This was a prospectively study and five patients with stage Ⅰ and Ⅱ mediastinal lymphomas were included continuously.The absolute target volume,the absolute OAR doses,and the relative doses to volume were compared between DIBH and free-breathing (FB) scans,based on the principles of the affected site irradiation and the butterfly field.The differences were analyzed using paired t test.Results The median age of these five patients was 30 years.Compared with FB scan,DIBH scan led to significant decreases in the gross tumor volume (GTV)(Δ=29.4 cm3,P=0.006) and the planning target volume (PTV)(Δ=322 cm3,P=0.005) before chemotherapy,while no significant difference in clinical target volume (CTV) was found.Meanwhile,the lung volume of DIBH scan was significantly increased (mean Δ=1456 cm3,P=0.001),while the heart width of DIBH scan was significantly reduced (Δ=1.3 cm,P=0.012),as compared with those of FB scan.The mean doses to the lung and heart were significantly lower in DIBH scan than in FB scan (heart:8.5±4.7 Gy vs.11.6±4.7 Gy,P=0.022;lung:7.6±1.1 Gy vs.11.6±1.4 Gy,P=0.000).The absolute target volume of the heart was significantly reduced at V15 and above in DIBH scan than in FB scan (all P<0.05).Relative doses to volume of the lung and heart were significantly reduced at each dose level (from V5 to V35) in DIBH scan than in FB scan (all P<0.05).Conclusions DIBH technique can significantly reduce PTV,enlarge lung volume,and reduce the mean dose and relative doses to volume of the lung and heart at each level (from V5 to V35) compared with FB scan in mediastinal lymphoma radiation.
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Objective To compare the exposure to heart and other organs of the application of DIBH (deep inspiration breath-hold)and FB(free breath)in the left breast cancer radiotherapy,and the relationship between CCD(cardiac contact distance)and heart dose was analyzed.Methods Thirty patients with left breast cancer were examined with CT scans using DIBH and FB respectively,and then the dose was calculated by TPS(treatment planning system).The dose of heart,left anterior descending branch and left ventricle were analyzed by DVH(dose volume histogram).FB-CCDax(Axial cardiac chest wall contact distance)and FB-CCDps(sagittal heart chest wall contact distance)in CT images were measured based on FB.Results The parameters showed that,in radiotherapy with the application of DBIH technology,the irradiated volume of heart, left anterior descending branch(LAD),left ventricle(LV)of were significantly lower than that in the organs in the FB,the mean dose(Dmean)of heart of the former was 0.8 Gy,compared with 2.7 Gy in the latter one(P<0.005).The Dmean of LAD was 4.0Gy,compared with 12.7Gy in the latter one(P<0.001); The Dmean of LV was 1.2Gy,compared with 3.6Gy in the latter one(P<0.005).In the DIBH and FB radiotherapy,the Dmean of the heart,left anterior descending branch and left ventricle was correlated with FB-CCDps,but not with FB-CCDax.Conclusion DIBH is a simple treatment technique that can effectively reduce the cardiac radiation dose without loss of target dose.FB-CCDps is a potential predictor of cardiac exposure,and the longer the FB-CCDps distance is,the higher the cardiac dose is.The study found that at least 70% of patients with left breast cancer would benefit from DIBH and reduce the radiation exposure to normal cardiac structures,so DIBH should be used as a routine clinical application.
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Objective To investigate the dosimetric differences among three types of breath hold mode ( free breath:FB, thoracic deep inspiration breath hold: T-DIBH, abdomen deep inspiration breath hold:A-DIBH) and to explore the optimal breath hold method in the postoperative radiotherapy of left-side breast cancer patients with minimum dose to normal tissues and organs at risk. Methods A total of eighteen patients with left-side breast cancer patients who underwent postoperative radiotherapy were enrolled in this study. Three CT simulation scans with three different breath hold method ( FB, T-DIBH, and A-DIBH ) were performed for each patient. Dosimetric differences were compared among plans generated on these three different CT image sets. Results There was no significant difference in the volume, mean dose, and homogeneity of planning target volume ( PTV) among plans generated from three different image sets (P>0. 05). The mean heart dose, mean LAD dose and mean ipsilateral lung dose in plans generated from CT image sets with FB, T-DIBH and A-DIBH were (3. 21 ± 1. 02), (1. 74 ± 0. 51), (1. 31 ±0. 41) Gy (W =171, P <0. 05), (34. 61 ± 13. 51), (14. 38 ±10. 20), (9. 21 ± 6. 53) Gy (W=171, P<0. 05), and (8. 31 ±2. 75), (7. 46 ±1. 96), (6. 89 ±1. 79) Gy (W=171, P<0. 05), respectively. Conclusions Compared with plans with FB, plans with DIBH ( T-DIBH and A-DIBH ) achieved lower cardiac, LAD and pulmonary doses. A-DIBH achieved a better normal dose reduction than T-DIBH.
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PURPOSE: We explored whether the deep inspiration breath hold (DIBH) technique using Abches during left-sided breast irradiation was effective for minimizing the amount of radiation to the heart and lung compared to free breathing (FB). MATERIALS AND METHODS: Between February and July 2012, a total of 25 patients with left-sided breast cancer underwent two computed tomography scans each with the DIBH using Abches and using FB after breast-conserving surgery. The scans were retrospectively replanned using standardized criteria for the purpose of this study. The DIBH plans for each patient were compared with FB plans using dosimetric parameters. RESULTS: All patients were successfully treated with the DIBH technique using Abches. Significant differences were found between the DIBH and FB plans for mean heart dose (2.52 vs. 4.53 Gy), heart V30 (16.48 vs. 45.13 cm3), V20 (21.35 vs. 54.55 cm3), mean left anterior descending coronary artery (LAD) dose (16.01 vs. 26.26 Gy, all p < 0.001), and maximal dose to 0.2 cm3 of the LAD (41.65 vs. 47.27 Gy, p = 0.017). The mean left lung dose (7.53 vs. 8.03 Gy, p = 0.073) and lung V20 (14.63% vs. 15.72%, p = 0.060) of DIBH using Abches were not different significantly compared with FB. CONCLUSION: We report that the use of a DIBH technique using Abches in breathing adapted radiotherapy for left-sided breast cancer is easily feasible in daily practice and significantly reduces the radiation doses to the heart and LAD, therefore potentially reducing cardiac risk.