Investigation of variability in image acquisition and contouring during 3D ultrasound guidance for partial breast irradiation.

Background: Three-dimensional ultrasound (3DUS) at simulation compared to 3DUS at treatment is an image guidance option for partial breast irradiation (PBI). This study assessed if user dependence in acquiring and contouring 3DUS (operator variability) contributed to variation in seroma shifts calculated for breast IGRT.

Methods: Eligible patients met breast criteria for current randomized PBI studies.

3D ultrasound can contribute to planning CT to define the target for partial breast radiotherapy.

Purpose: The role of three-dimensional breast ultrasound (3D US) in planning partial breast radiotherapy (PBRT) is unknown. This study evaluated the accuracy of coregistration of 3D US to planning computerized tomography (CT) images, the seroma contouring consistency of radiation oncologists using the two imaging modalities and the clinical situations in which US was associated with improved contouring consistency compared to CT.

Materials And Methods: Twenty consecutive women with early-stage breast cancer were enrolled prospectively after breast-conserving surgery.