Dose-volume characteristics of a 50-kV electronic brachytherapy source for intracavitary accelerated partial breast irradiation.
OBJECTIVE
To describe dose-volume data from a 50-kV electronic brachytherapy source in intracavitary accelerated partial breast irradiation.


METHODS
Three spherical balloon applicators were imaged on a CT scanner in a water phantom and inflated throughout their suggested fill volume range. The planning target volume (PTV) was defined as a 1-cm margin around the balloon surface. Plans were created achieving 80%, 85%, and 90% coverage of the PTV, with a prescription dose of 34Gy in 10 fractions. The PTV, V(90), V(100), V(150), V(200), and V(300) were recorded for each plan.


RESULTS
For 80% target coverage, the V(200) varies from 11 to 14 cm(3) and the V(150) from 26 to 49 cm(3) over all the balloon applicators and fill volumes. For 85% coverage, the V(200) varies from 14 to 18 cm(3) and the V(150) from 27 to 53 cm(3). For 90% coverage, the V(200) varies from 16 to 22 cm(3) and the V(150)cm(3) from 30 to 61 cm(3).


CONCLUSIONS
Fifty-kilovolt electronic brachytherapy can provide PTV coverage similar to (192)Ir in the setting of intracavitary accelerated partial breast irradiation.
Department of Radiation Oncology, Stanford University, 875 Blake Wilbur Drive, Stanford, CA 94305, USA. melanies94028@yahoo.com
Melanie C
MC
Smitt
Rob
R
Kirby
D001918:Brachytherapy / Q000295:instrumentation*; D001940:Breast; D001943:Breast Neoplasms / Q000532:radiotherapy*; D002404:Catheterization / Q000295:instrumentation*; D004307:Dose-Response Relationship, Radiation; D004867:Equipment Design; D005260:Female; D006801:Humans; D011880:Radiotherapy Planning, Computer-Assisted / Q000295:instrumentation*; D016896:Treatment Outcome