| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 2161087 | Radiotherapy and Oncology | 2007 | 5 Pages |
PurposeStatic multileaf collimated field-in-field forward-planned intensity-modulated radiation treatment (FiF-IMRT) has been shown to improve dose homogeneity compared to conventional wedged fields. However, a direct comparison of the scattered dose to the contralateral breast resulting from wedged and FiF-IMRT plans remains to be documented.MethodsThe contralateral scattered breast dose was measured in a custom-designed anthropomorphic breast phantom in which 108 thermoluminescent dosimeters (TLDs) were volumetrically placed every 1–2 cm. The target phantom breast was treated to a dose of 50 Gy using three dose compensation techniques: No medial wedge and a 30-degree lateral wedge (M0-L30), 15-degree lateral and medial wedges (M15-L15), and FiF-IMRT. TLD measurements were compared using analysis of variance.ResultsFor FiF-IMRT, the mean doses to the medial and lateral quadrants of the contralateral breast were 112 cGy (range 65–226 cGy) and 40 cGy (range 18–91 cGy), respectively. The contralateral breast doses with FiF-IMRT were on average 65% and 82% of the doses obtained with the M15-L15 and M0-L30 techniques, respectively (p < 0.001). Compared to the M15-L15 technique, the maximum dose reduction obtained with FiF-IMRT was 115 cGy (range 13–115 cGy).ConclusionsThe dose to the contralateral breast is significantly reduced with FiF-IMRT compared to wedge-compensated techniques. Although long-term follow-up is needed to establish the clinical relevance of this finding, these results, along with the previously reported improvement in ipsilateral dose homogeneity, support the use of FiF-IMRT if resources permit.
