ESTRO 2022 - Abstract Book

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Abstract book

ESTRO 2022

group 2 only delineated the heart for patients receiving non-standard RT. Instead, group 2 prioritised dose constraints to delineation of left anterior descending coronary artery above CTV IMN coverage until E2. Figure 1 shows the median V90% CTV IMN coverage and the average delineated volume for IMN each year for 3479 patients. After E2, 98% of all LSP had IMN delineated with a median CTV V90% of 93% (IQR 79% - 98%). Over the whole period, 98% of the right sided patients had IMN delineated with a median CTV V90% of 95% (IQR 76% -100%). After E3, the mean volume of IMN converged to an average of 7.4mL (SD=3.4). Figure 2 shows the mean heart dose (MHD) and volume of the heart for centres in group 1 over time. The volume of the heart stabilised after E1 and a small increase in MHD after E2 was detected associated with the increase in CTV IMN V90% for LSP.

Conclusion