Development and Validation of a Heart Atlas to Study Cardiac Exposure to Radiation Following Treatment for Breast Cancer

• Published in: International journal of radiation oncology, biology, physics Vol. 79; no. 1; pp. 10 - 18
• Main Authors: Feng, Mary, M.D, Moran, Jean M., Ph.D, Koelling, Todd, M.D, Chughtai, Aamer, M.D, Chan, June L., M.D, Freedman, Laura, M.D, Hayman, James A., M.D, Jagsi, Reshma, M.D., D. Phil, Jolly, Shruti, M.D, Larouere, Janice, M.D, Soriano, Julie, M.D, Marsh, Robin, C.M.D, Pierce, Lori J., M.D
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01.01.2011; Elsevier
• Subjects: ARTERIES; Biological and medical sciences; BLOOD VESSELS; BODY; Breast cancer; Breast Neoplasms - radiotherapy; Cardiac atlas; Cardiac dysfunction; CARDIOVASCULAR SYSTEM; Clinical trials; Computed tomography; COMPUTERIZED TOMOGRAPHY; Contrast Media; CORONARIES; Coronary Angiography - methods; coronary artery; DIAGNOSTIC TECHNIQUES; DISEASES; DOSES; Female; GLANDS; Gynecology. Andrology. Obstetrics; HEART; Heart - diagnostic imaging; Heart - radiation effects; Hematology, Oncology and Palliative Medicine; Humans; Mammary gland diseases; MAMMARY GLANDS; Medical Illustration; Medical sciences; MEDICINE; NEOPLASMS; Normal-tissue sparing; NUCLEAR MEDICINE; Observer Variation; Oncology; ORGANS; Radiation; RADIATION DOSES; Radiation Injuries - prevention & control; RADIOLOGY; RADIOLOGY AND NUCLEAR MEDICINE; RADIOTHERAPY; TESTING; THERAPY; Thoracic radiotherapy; TOMOGRAPHY; Tomography, X-Ray Computed; TOXICITY; Tumors; VALIDATION; Cardiac atlas; Breast cancer; Thoracic radiotherapy; Cardiac dysfunction; Normal-tissue sparing; Heart; Breast disease; Thorax; Malignant tumor; Radiotherapy; Mammary gland diseases; Treatment; Circulatory system; Atlas (bone); Cancer
• ISSN: 0360-3016; 1879-355X
• DOI: 10.1016/j.ijrobp.2009.10.058

Purpose Cardiac toxicity is an important sequela of breast radiotherapy. However, the relationship between dose to cardiac structures and subsequent toxicity has not been well defined, partially due to variations in substructure delineation, which can lead to inconsistent dose reporting and the failure to detect potential correlations. Here we have developed a heart atlas and evaluated its effect on contour accuracy and concordance. Methods and Materials A detailed cardiac computed tomography scan atlas was developed jointly by cardiology, cardiac radiology, and radiation oncology. Seven radiation oncologists were recruited to delineate the whole heart, left main and left anterior descending interventricular branches, and right coronary arteries on four cases before and after studying the atlas. Contour accuracy was assessed by percent overlap with gold standard atlas volumes. The concordance index was also calculated. Standard radiation fields were applied. Doses to observer-contoured cardiac structures were calculated and compared with gold standard contour doses. Pre- and post-atlas values were analyzed using a paired t test. Results The cardiac atlas significantly improved contour accuracy and concordance. Percent overlap and concordance index of observer-contoured cardiac and gold standard volumes were 2.3-fold improved for all structures ( p < 0.002). After application of the atlas, reported mean doses to the whole heart, left main artery, left anterior descending interventricular branch, and right coronary artery were within 0.1, 0.9, 2.6, and 0.6 Gy, respectively, of gold standard doses. Conclusions This validated University of Michigan cardiac atlas may serve as a useful tool in future studies assessing cardiac toxicity and in clinical trials which include dose volume constraints to the heart.