NCCN guidelines
Version 3.2016:
Gastric cancer
Liver:
60% < 30 Gy; mean dose < 25 Gy
Kidneys:
2/3 of one Kidney < 20 Gy
Spinal cord:
< 45 Gy
Heart:
1/3 heart < 40 Gy; left ventricle ALARA
Lungs