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Table 3 Plan evaluation parameters and dose statistics

From: Multicriteria optimization enables less experienced planners to efficiently produce high quality treatment plans in head and neck cancer radiotherapy

Parameters Conventional IMRT MCO IMRT Difference p -value
Dose-volume values (Gy)     
PTV (boost) D98% 66.4 ± 2.1 66.9 ± 1.1 −0.5 ± 0.5 0.03
PTV (boost) 70.2 ± 0.5 70.1 ± 0.3 0.2 ± 0.1 0.33
PTV (boost) D2% 73 ± 1.2 72.4 ± 0.7 0.6 ± 0.3 0.04
PTV (prophylactic) D98% 52 ± 0.7 52.5 ± 1.2 −0.4 ± 0.3 0.07
PTV (prophylactic) 54.6 ± 0.5 54.8 ± 1.0 −0.2 ± 0.2 0.53
Integral dose 13.9 ± 4.5 12.9 ± 4.0 0.9 ± 1.4 <0.001
Ring 1 cm around PTV 46.2 ± 2.6 45.0 ± 2.2 1.1 ± 0.8 0.008
Ring 6 cm around PTV 16.9 ± 3.2 15.0 ± 2.5 1.9 ± 0.9 <0.001
Spinal cord (D1%) 45.3 ± 3.9 44.1 ± 4.4 1.2 ± 1.3 0.17
Brain D1% 27.8 ± 14.5 27.5 ± 16.1 0.2 ± 4.8 0.31
Parotid gland (contra) 28.1 ± 11.8 23.0 ± 11.2 5.1 ± 8.1 <0.002
Parotid gland (ipsi) 39.1 ± 11.7 36.0 ± 11.1 3.0 ± 11.9 0.02
Superior PCM 58.8 ± 9.5 58.9 ± 10.2 −0.1 ± 3.1 0.91
Middle PCM 55.3 ± 14.0 56.3 ± 12.1 −1.0 ± 4.1 0.79
Inferior PCM 51.2 ± 16.8 52.2 ± 15.9 −1.0 ± 5.2 0.46
Supraglottic larynx 55.5 ± 15.3 57.3 ± 13.7 −1.9 ± 4.6 0.02
Esophagus inlet muscle 44.8 ± 12.2 44.1 ± 11.0 0.7 ± 3.7 0.28
Cricopharyngeus 48.6 ± 13.8 48.5 ± 13.6 0.1 ± 4.3 0.73
NTCP values (%)     
Xerostomia [contra] 27.1 ± 20.9 18.7 ± 19.2 8.4 ± 7.4 <0.003
Xerostomia [ipsi] 48.2 ± 25.8 41.8 ± 24.0 6.4 ± 14.3 0.03
Dysphagia 35.4 ± 14.7 36.9 ± 14.7 −1.5 ± 4.7 0.11
Plan evaluation     
CI 95% (PTV boost) 1.30 ± 0.12 1.28 ± 0.07 0.02 ± 0.03 0.98
CI 95% (PTV prophylactic) 1.54 ± 0.15 1.55 ± 0.13 −0.02 0.04 0.65
Monitor Units (#) 590 ± 135 672 ± 157 −82 ± 46 0.02
Total planning time (min) 205 43 ± 12 162 -
  1. Abbreviations: PTV planning target volume, PCM pharyngeal constrictor muscle, NTCP normal tissue complication probability, CI 95% conformity index of 95% isodose with PTV. Items with statistically significant differences (structure related: p < 0.003 else: p < 0.05) in bold.