Whole-brain irradiation with hippocampal sparing and dose escalation on metastases: neurocognitive testing and biological imaging (HIPPORAD) – a phase II prospective randomized multicenter trial (NOA-14, ARO 2015–3, DKTK-ROG)

Table 4 Organs at risk (OAR)

Parameter	Per Protocol	Minor Deviation	Major Deviation
Hippocampus in Treatment Arm A (HA-WBRT+SIB)	D_98% ≤ 9Gy D_2% ≤ 17Gy	9 Gy < D_98% ≤ 10Gy 17Gy < D_2% ≤ 18Gy	D_98% > 10Gy D_2% > 18Gy
Hippocampus in Treatment Arm B (WBRT+SIB)	D_98% ≥ 25Gy	24Gy ≤ D_98% < 25Gy	D_98% < 24Gy
Optical nerves Chiasm	D_2% ≤ 33Gy	33Gy < D_2% ≤ 35Gy (36Gy^a)	D_2% > 35Gy (36Gy^a)
Optical nerve, one-sided	D_2% ≤ 35Gy	35Gy < D_2% ≤ 37Gy	D_2% > 37Gy
Retina, one-sided	D_2% ≤ 33Gy	33Gy < D_2% ≤ 35Gy (49Gy^a)	D_2% > 35Gy (49Gy^a)
Lenses	D_2% ≤ 7Gy	7Gy < D_2% ≤ 10Gy	D_2% > 10Gy
Inner ear (in case of bilateral involvement)	D_2% ≤ 33Gy	33Gy < D_2% ≤ 35Gy (36Gy^a)	D_2% > 35Gy (36Gy^a)
Eyes	D_2% ≤ 33Gy	33Gy < D_2% ≤ 35Gy	D_2% > 35Gy
Brain stem (if metastasis inside the brainstem: brain stem-PTV_met)	D_2% ≤ 33Gy	33Gy < D_2% ≤ 35Gy (51Gy^a)	D_2% > 35Gy (51Gy^a)

ISSN: 1471-2407