Background and purpose: This study aims at evaluating the effectnof deep-inspiration breath hold (DIBH) on target coverage and dosento organs at risk in a large series of breast cancer patients.
Materials and methods: Clinical dose plans for 319 breast cancernpatients were evaluated: 144 left-sided patients treated with DIBHnand 175 free-breathing (FB) patients (83 left-sided and 92nright-sided). All patients received whole breast irradiation withntangential fields, based on a forward-planned intensity-modulatednradiation therapy (IMRT) technique. Dose to heart, ipsi-lateralnlung and ipsi-lateral breast were assessed and median valuesncompared between patient groups.
Results: Comparing group median values, DIBH plans show largenreductions of dose to the heart compared with left-sided FB plans;nV20Gy (relative volume receiving ≥ 20 Gy) for the heartnis reduced from 7.8% to 2.3% (-70%, p < 0.0001),nV40Gy from 3.4% to 0.3% (-91%, p < 0.0001) and meanndose from 5.2 to 2.7 Gy (-48%, p < 0.0001). Lung dose also showsna small reduction in V20Gy (p < 0.04), while medianntarget coverage is slightly improved (p = 0.0002).
Conclusions: In a large series of clinical patients we find thatnimplementation of DIBH in daily clinical practice results innreduced irradiation of heart and lung, without compromising targetncoverage.
Henrik D. Nissen, Ane L. Appelt