Target Volume Determination 2015

CTV1: the tumor + margin

GTV + corresponding mesorectum

Microscopic tumor deposits in the Mesorectum: 38% Outer Region of the Mesorectum: 25% Distal tumor deposits in the mesorectal fat 3 cm from the cancer: 6.5%

Wang et al. Int J Colorectal dis 2005

Myerson et al IJROBP 2009