Anterior Myocardial Territory May Replace the Heart as Organ at Risk in Intensity-Modulated Radiotherapy for Left-Sided Breast Cancer

Tan, Wenyong; Dong, Liang; Xue, Chenbin; Xu, Jinghua; Li, Beihui; Chen, Zhengwang; Hu, Desheng; Wang, Xionghong

doi:10.1016/j.ijrobp.2011.03.009

Cited by 30 publications

(15 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…We have previously reported detailed definitions of the heart, AMT, and left ventricle 9,10. Briefly, the heart includes all visible myocardium and excludes large vessels (Figure 1A and B).…”

Section: Methodsmentioning

confidence: 99%

“…The interventricular septum was also included in the left ventricle (Figure 1A and B). The AMT9,10 comprised the myocardium from the anterior surface of the heart up to 1.0 cm posteriorly and the main branches of the coronary arteries at the anterior portion of the heart, such as the left anterior descending artery, left circumflex artery, and right marginal artery as well as the left and right main coronary arteries (Figure 1A–C). The left and right main coronary arteries were defined from their origin in the aortic sinus to the first branches (Figure 1A and C).…”

Section: Methodsmentioning

confidence: 99%

“…Clinically however, the heart is generally considered a whole organ at risk during thoracic RT,4 whereby possible heterogeneity in the radiobiological response of various substructures is not taken into consideration. In previous studies,9,10 we specifically defined the anterior part of the heart as the anterior myocardial territory (AMT). We have shown that the AMT can replace the heart as an independent cardiac substructure, with the aim of decreasing the cardiac radiation dose during breast intensity-modulated RT.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Estimation of the displacement of cardiac substructures and the motion of the coronary arteries using electrocardiographic gating

Tan¹,

Xu²,

Wang³

et al. 2013

OTT

Self Cite

View full text Add to dashboard Cite

PurposeThe aim of this study was to quantify the displacement of cardiac substructures, including the anterior myocardial territory (AMT), left ventricle, and coronary arteries during a normal cardiac cycle.Materials and methodsComputed tomography (CT) images with retrospective electrocardiographic gating of 17 eligible patients were obtained. All images were reconstructed automatically for the end-diastolic and end-systolic phases. CT scanning without contrast at a random phase and a selected vertebral body were used as references to measure three-dimensionaldisplacements of the cardiac substructures.ResultsThe displacement between the end-diastolic and end-systolic phases (Dd-s) was greater than that between the end-systolic and random phases and between the end-diastolic and random cardiac phases. The largest displacements for the heart were in the left, posterior, and inferior directions with an average Dd-s of approximately 4–6 mm. The average Dd-s for the AMT and left ventricle was 1.2–2.7 mm in the anterior and right directions, 4.3–7.8 mm in left and posterior directions, and 4.9–6.3 mm in superior and inferior directions. For the coronary arteries, the average Dd-s was 2.8–5.9 mm in the anterior-posterior direction, 3.5–6.6 mm in left-right direction, and 3.8–5.3 mm in the superior-inferior direction. Inter-observer agreement was excellent for the heart, AMT, and left ventricle (kappa coefficient, >0.75 for all) and good for most coronary arteries in three dimensions (kappa coefficient, 0.511–0.687). The Dd-s did not differ significantly between men and women.ConclusionMost average displacements of the cardiac substructures and coronary arteries were 3–8 mm in three dimensions. These findings will be useful to accurately estimate the radiation dose to cardiac substructures during thoracic radiation and to evaluate the risk of radiation-related heart disease.

show abstract

Section: Methodsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Estimation of the displacement of cardiac substructures and the motion of the coronary arteries using electrocardiographic gating

Tan¹,

Xu²,

Wang³

et al. 2013

OTT

Self Cite

View full text Add to dashboard Cite

show abstract

“…Nonetheless, maximum doses to small but presumably relevant parts of the anterior part of the LV (“anterior myocardial territory,” AMT; based on Tan et al. [43]) were up to 47.2 Gy. The mean and maximum doses to the LAD were 9.2 (2.1–46.2) Gy and 24.6 (2.8–49.6) Gy, respectively.…”

Section: Value Of Mean Heart Dosementioning

confidence: 99%

Heart toxicity from breast cancer radiotherapy

et al. 2018

View full text Add to dashboard Cite

BackgroundLate cardiac toxicities caused by (particularly left-sided) breast radiotherapy (RT) are now recognized as rare but relevant sequelae, which has prompted research on risk structure identification and definition of threshold doses to heart subvolumes. The aim of the present review was to critically discuss the clinical evidence on late cardiac reactions based on dose-dependent outcome reports for mean heart doses as well as doses to cardiac substructures.MethodsA literature review was performed to examine clinical evidence on radiation-induced heart toxicities. Mean heart doses and doses to cardiac substructures were focused upon based on dose-dependent outcome reports. Furthermore, an overview of radiation techniques for heart protection is given and non-radiotherapeutic aspects of cardiotoxicity in the multimodal setting of breast cancer treatment are discussed.ResultsBased on available findings, the DEGRO breast cancer expert panel recommends the following constraints: mean heart dose <2.5 Gy; DmeanLV (mean dose left ventricle) < 3 Gy; V5LV (volume of LV receiving ≥5 Gy) < 17%; V23LV (volume of LV receiving ≥23 Gy) < 5%; DmeanLAD (mean dose left descending artery) < 10 Gy; V30LAD (volume of LAD receiving ≥30 Gy) < 2%; V40LAD (volume of LAD receiving ≥40 Gy) < 1%.ConclusionIn addition to mean heart dose, breast cancer RT treatment planning should also include constraints for cardiac subvolumes such as LV and LAD. The given constraints serve as a clinicians’ aid for ensuring adequate heart protection. The individual decision between sufficient protection of cardiac structures versus optimal target volume coverage remains in the physician’s hand. The risk of breast cancer-specific mortality and a patient’s cardiac risk factors must be individually weighed up against the risk of radiation-induced cardiotoxicity.

show abstract

“…Coronary arteries were schematically delineated as an area of the anterior wall of the heart (Fig. 3) [12]. A single isocentric VMAT plan was prepared by a medical physicist using the Eclipse treatment planning system (version 10).…”

Section: Imaging and Treatment Planningmentioning

confidence: 99%

Volumetric Modulated Arc Therapy followed by bilateral mastectomy for treating synchronous cancer and sarcoma — a rare case report

Gałecki¹,

Bęczkowska²,

Mężeński³

2017

Nowotwory. Journal of Oncology

View full text Add to dashboard Cite

Purpose. Bilateral postmastectomy irradiation (BPMI) poses a challenge to radiotherapists. The difficulty lies whenever targets are large, irregular and lying at different depths. When breathing movements occur it is very hard to obtain homogenous dosing on such targets and also to not exceed those doses acceptable for at-risk organs, particularly the lungs and heart. The presented study is an example of using a single isocenter Volumetric Modulated Arc Therapy (VMAT) technique for a BPMI case. Materials and methods. We report the case of a 66-year-old woman with simultaneous malignant sarcoma of the right breast and an invasive ductal carcinoma of the left breast. After modified radical mastectomy of the left breast and simple mastectomy of the right breast, the patient underwent adjuvant irradiation of the bilateral chest wall and left axillary and supraclavicular nodes region. Planning Target Volumes (PTV) and organs at risk (OAR) were delineated on CT scans. A single isocenter VMAT plan was created. The radiotherapy consisted of 50 Gy delivered in 2 Gy per fraction to the left side and 56.5 Gy delivered in 2.25 Gy per fraction to the right side in 25 fractions, five times a week over 5 weeks. Results. The left and right CTV (Clinical Target Volume) received 90% of the prescribed dose in 100% of the CTV volume. The mean heart dose was 14.4 Gy and V25 for the heart was 8.9%. The mean lung dose was 16.6 Gy and the V20 for both lungs was 28.3%. The dose to the anterior wall area of the heart was exceeded according to established constraints, but was accepted. One session of irradiation lasted about four minutes during which the patient received 595 monitor units. The treatment was carried out without interruption and complications. The early and late skin reaction was assessed as being second grade. After one year of follow-up, the patient did not present any serious side effects or recurrence. Conclusions. Synchronous irradiation of both sides of the chest wall after bilateral mastectomy with a single isocenter VMAT technique is possible and well tolerated. NOWOTWORY J Oncol 2017; 67, 1: 48-53

show abstract

Anterior Myocardial Territory May Replace the Heart as Organ at Risk in Intensity-Modulated Radiotherapy for Left-Sided Breast Cancer

Cited by 30 publications

References 45 publications

Estimation of the displacement of cardiac substructures and the motion of the coronary arteries using electrocardiographic gating

Estimation of the displacement of cardiac substructures and the motion of the coronary arteries using electrocardiographic gating

Heart toxicity from breast cancer radiotherapy

Volumetric Modulated Arc Therapy followed by bilateral mastectomy for treating synchronous cancer and sarcoma — a rare case report

Contact Info

Product

Resources

About