Table 2.

QUANTEC recommendations for the threshold values of the dose-volume metrics for the organs at risk and the corresponding clinical endpoints.

Organ	Volume segmented	Endpoint	Dose-volume metric	Rate (%)
Liver	Whole liver, GTV	Classic RILD	Dmean <15 Gy (3 fx SRS)	<5
			Dmean <20 Gy (6 fx SRS)
	>700 cm3 of normal liver	Classic RILD	VD<15 >700 cm3	<5
Right kidney	Bilateral whole kidney	Clinically relevant renal dysfunction	Dmean <28 Gy	<50
Lungs	Whole organ	Symptomatic pneumonitis	Dmean <13 Gy	10
Spinal cord	Partial organ	Myelopathy	Dmax <20 Gy (3 fx SRS)	1
Esophagus	Whole organ	Grade ≥2 acute esophagitis	V35 <50%	<30
		Grade ≥3 acute esophagitis	Dmean <34 Gy	5–20

Abbreviations: QUANTEC, Quantitative Analyses of Normal Tissue Effects in the Clinic; GTV, gross tumor volume; RILD, radiation-induced liver disease; fx, fraction; SRS, stereotactic radiosurgery.

Note: Data from Marks LB et al. Use of normal tissue complication probability models in the clinic. Int J Radiat Oncol Biol Phys. 2010;76:S10-9.