Comparison of Wedge versus Segmented Techniques in Whole Breast Irradiation

Abstract

Partial volume segments can replace wedges for improved dose coverage and homogeneity in the PTV. The ST causes significantly less scattered dose to extra-target organs. This may have implications for long-term risks after exposure to low radiation doses.

Effect of Breathing Motion in Radiotherapy of Breast Cancer

“…The segment-based techniques offered the possibility of patient-specific intensity modulation in craniocaudal direction improving dose homogeneity with reduced volumes of hot spots, which is in good agreement with previous studies [3,18,23]. The optimization of dose was performed with forward planned segments delivered in step-and-shoot technique [27,36].…”

“…The second technique was based on beam arrangements with the same gantry angles but segments were used to improve target dose homogeneity. The segment shape was created in the beam's eye view using a method described previously [6,15,18]. Beam segments were designed by selecting sets of isodose levels and fitting multileaf collimator leaves to a best approximation of their shape thus eliminating a physical wedge.…”

“…After breast-conserving tumorectomy, adjuvant whole-breast irradiation is the standard treatment for early breast cancer [26]. Depending on the shape of the planning target volume (PTV), two basic beam arrangements can be applied: the tangential [6,9,18,27,36] or multibeam technique [2]. For tangential fields, the beam fluence is modified by wedges or multiple segments to improve dose homogeneity in the target [6,18,27,30].…”

Procedure for creating a three-dimensional (3D) model for superficial hyperthermia treatment planning

“…Since HT is almost always used in combination with RT, it would be beneficial to integrate the RT CT scan in both planning techniques [1,12,17,18,19,27,32]. However, this is not possible for SHT and deep HT treatments, since the positioning for RT differs from that for HT.…”

Radiobiological Comparison of Hypofractionated Accelerated Partial-Breast Irradiation (APBI) and Single-Dose Intraoperative Radiotherapy (IORT) with 50-kV X-Rays

“…Although the rationale varies between different studies [16], it is generally assumed that recurrences after breast-conserving surgery occur near the site of a tumor and that part of the patients may not need adjuvant radiotherapy to the whole breast [6,15]. APBI may be applied by interstitial brachytherapy, brachytherapy applicators, and intensity-modulated external-beam radiotherapy [19,21,25,32,36].…”