Should breathing adapted radiotherapy also be applied for right-sided breast irradiation?

Figures & data

Figure 1. Mean (total) lung dose for the fourteen patients planned locally, locoregionally without IMN, and locoregionally with IMN, both in FB and in vmDIBH.

Figure 2. Volume of total lung receiving more than 20 Gy (V20Gy) for the fourteen patients planned locally, locoregionally without IMN, and locoregionally with IMN, both in FB and in vmDIBH.

Table 1. Comparison of average dose parameters of 14 right sided breast cancer patients locally irradiated (breast), locoregionally irradiated (Breast + perivlav) and locoregionally irradiated with IMN involved (Breast + periclav + IMN), both in free breathing (FB) and breath-hold (vmDIBH) for the heart, the ipsilateral and total lung and contralateral breast.

	Breast		Breast + periclav		Breast + periclav + IMN
	FB	vmDIBH	FB	vmDIBH	FB	vmDIBH
PTV
V95%(%)	94.3 ± 2.4	94.6 ± 2.3	96.4 ± 2.5	96.7 ± 2.7	96.3 ± 2.0	96.2 ± 1.9
D2% (%)	105.8 ± 1.7	106.8 ± 1.2	106.4 ± 2.6	107.7 ± 2.7	111.6 ± 3.3	111.6 ± 2.7
Heart
V5Gy (%)	0.1 ± 0.1	0.0 ± 0.0	0.1 ± 0.1	0.0 ± 0.0	7.3 ± 6.9	4.5 ± 4.1
MHD (Gy)	0.40 ± 0.14	0.39 ± 0.12	0.44 ± 0.14	0.42 ± 0.12	1.57 ± 1.08	1.18 ± 0.52
Ipsilateral lung
V20Gy (%)	15.3 ± 6.5	14.1 ± 5.7	24.5 ± 7.1	20.1 ± 6.2*	42.6 ± 8.2	35.1 ± 6.3*
MLD (Gy)	7.43 ± 2.49	6.84 ± 2.20	11.24 ± 2.57	9.58 ± 2.11*	18.51 ± 3.22	16.00 ± 2.82*
Lung
V20Gy (%)*	8.8 ± 3.7	7.5 ± 3.1	14.0 ± 3.3	11.0 ± 3.4*	24.4 ± 5.3	19.6 ± 4.2*
MLD (Gy)*	4.25 ± 1.41	3.80 ± 1.20	6.47 ± 1.57	5.34 ± 1.15*	10.69 ± 2.07	9.00 ± 1.73*
Contralateral breast MBD (Gy)	0.20 ± 0.08	0.21 ± 0.09	0.23 ± 0.09	0.23 ± 0.10	0.77 ± 0.45	0.85 ± 0.64

Abbreviations: FB = free breathing, vmDIBH = voluntary moderately deep inspiration breath-hold, IMN = internal mammary lymph nodes, Periclav = periclavicular lymph nodes, VxGy = the fractional volume of the organ receiving x Gy, MHD = mean heart dose, MLD = mean lung dose, D_2%(%) is the maximum dose in the PTV given to 2% of the volume, in percentages of the prescribed dose. Data are shown as mean values with one standard deviation. *Comparison FB and vmDIBH with Wilcoxon test p < 0.005: statistically significant difference between vmDIBH and FB.