Table 2.

Mean differences between internal target volume concept (ITV) and optimization of the surrounding isodose (OSI)

	P105	P125	P150
Δ DMin in %	3.6 ± 0.7	17.8 ± 4.0	37.1 ± 8.9
Δ Margin in mm	3.3 ± 1.6	3.6 ± 2.3	4.3 ± 3.0
Δ DMean Surr in %	7.8 ± 3.0	6.4 ± 4.3	4.9 ± 3.1

Abbreviations: absolute increase in minimum target dose Δ D_Min, absolute increase in margin size Δ Margin, absolute increase in mean dose to surrounding region Δ D_{Mean Surr}