A heart atlas for breast radiation therapy and the influence of delination education on both intra and interobserver variability
JAPANESE JOURNAL OF RADIOLOGY, vol.37, no.5, pp.420-430, 2019 (SCI-Expanded, Scopus)
- Publication Type: Article / Article
- Volume: 37 Issue: 5
- Publication Date: 2019
- Doi Number: 10.1007/s11604-019-00819-1
- Journal Name: JAPANESE JOURNAL OF RADIOLOGY
- Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
- Page Numbers: pp.420-430
- Keywords: Breast radiotherapy, Heart atlas, Cardiac subunit delineation
- Dokuz Eylül University Affiliated: Yes
Abstract
PurposeWe developed a heart atlas for breast radiation therapy and evaluated the influence of education on intra and inter-observer similarity, and cardiac dose reporting.Materials and methodsThe data of 16 left breast cancer patients were analyzed. Eight observers delineated heart and cardiac subunits [left (LCA) and right (RCA) coronary arteries, left anterior descending artery (LAD), bilateral atrium and ventricles] before the education. A radiologist and radiation oncologist developed the atlas and delineated the gold standard (GS) volumes. Observers repeated the delineation after education. RT plans were made for pre/post-atlas contours. The similarity was assessed by Dice (DSC) and Jaccard (JSC) similarity coefficient indices. The absolute difference rate was calculated for the dose analysis.ResultsThe inter-observer similarity increased in heart and all subunits. The intra-observer similarity showed a heterogeneous distribution. The absolute difference rate in dose reporting was statistically significant for the bilateral atrium, right ventricle, LAD, LCA+LAD, RCA's maximum doses (p<0.05). The maximum dosereporting differences from the GS decreased from 16.9 to 8.9% for LAD (p=0.011); from 14.8 to 9.3% for LCA+LAD (p=0.010).ConclusionThe cardiac atlas reduces the intra-interobserver differences and improves dosereporting consistency. The first intra-observer similarity analysis was made in our study and revealed the need for repeated education to increase the consistency.