How do you approach treatment planning for preoperative radiation therapy in gastric cancer?  

If considering that it is not gastroesophageal junction, what margin do you place on the clipped GTV to formulate CTV? Is there any role for SIB to PET-avid lymph nodes? Do you do 4DCT, treat patient NPO?

Any details on how preoperative chemoradiation is done would be appreciated. There do not seem to be any publicly available radiation therapy planning guidelines from TOPGEAR or CRITICS-II.