University of Agriculture Faisalabad, Pakistan
Meltem Kirli has completed her medical school at the age of 24years from Hacettepe University and radiation oncology residency from Dokuz Eylul University School of Medicine. Until February 2019, she worked in Erzurum Regional Training and Research Hospital, Department of Radiation Oncology as the head of the department. In 2018, she made observations on brachytherapy and stereotactic radiation therapy at Leiden University Medical Center. She continues her work at Kocaeli State Hospital
Purpose: We developed a heart atlas for breast radiation therapy and evaluated the influence of education on intra and interobserver similarity and cardiac dose reporting.
Materials and Methods: The 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.
Results: The 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 dose reporting 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).
Conclusion: The cardiac atlas reduces the intra interobserver differences and improves dose reporting consistency. The first intra-observer similarity analysis was made in our study and revealed the need for repeated education to increase consistency.