Table 3. Dose–volume histogram parameters (Gy) for treatments with daily imaging and for a simulated option with imaging for four fractions followed by the patient positioned on for fractions 5 to n. A comparison of cases with isotropic 10 mm and adapted (anisotropic) PTV margins.

Patient	Structure	Parameter	10 mm 3D PTV margins		Adapted 3D PTV margins
			Planning dose	Simulation dose	Planning dose	Simulation dose
A	GTV	D99%	72.2	71.5	72.0	71.1
	PTV70	D99%	69.5	57.9	69.1	58.1
	Bladder	D15%	61.5	64.7	58.5	60.6
		D7cc	72.1	72.1	69.4	66.8
		D30cc	63.7	51.2	59.5	58.1
	Rectum	D15%	68.5	66.7	62.6	63.4
		D15cc	60.3	59.0	56.9	56.9
B	GTV	D99%	74.0	73.97	72.8	72.6
	PTV	D99%	69.4	62.2	71.1	58.4
	Bladder	D15%	72.3	74.1	66.1	70.2
		D7cc	74.5	75.5	73.7	74.8
		D30cc	68.3	71.4	61.4	65.6
	Rectum	D15%	70.3	64.9	64.9	60.8
		D15cc	52.3	52.1	50.6	50.9

PTV, planning target volume; 3D, three-dimensional; GTV, gross tumour volume.