ESTRO 2024 - Abstract Book

S3605

Physics - Dose prediction, optimisation and applications of photon and electron planning

ESTRO 2024

and H arc3 (0,64±0,07 and 0,09±0,01 respectively) compared to CONV (0,40±0,09 and 0,11±0,02 respectively). Beam on time and total MUs were lowest for H arc2 (0,939±0,84 min; 602,7±42,00 MUs respectively) and comparable to CONV (1,005±0,12 min; 562,2±82,82 MUs respectively).

Conclusion:

Dosimetric differences were observed in the hybrid plans based on the arc geometries. H arc2 plans resulted in decreased high-dose level to the heart and ipsilateral lung, better CI and HI for the targets, comparable V 5Gy and V 10Gy for the heart and contralateral OARs, total MUs and beam-on time compared to CONV. Thus, in scenarios where CONV technique leads to unsatisfactory results, hybrid planning with H arc2 arc geometry may benefit patients where volume of ipsilateral OARs in the field is high (e.g., in free breathing treatment) or in scenarios where fat in the upper flank area challenges conformity and homogeneity.

Keywords: Left Breast, hybrid planning,arc geometry

References:

1) Das Majumdar SK, Amritt A, Dhar SS, Barik S, Beura SS, Mishra T, et al. A Dosimetric Study Comparing 3D-CRT vs. IMRT vs. VMAT in Left-Sided Breast Cancer Patients After Mastectomy at a Tertiary Care Centre in Eastern India.