Gynae BT_Lucknow_2018

Dose volume effect for acute bowel, impact of V40 and V15

Fiorino IJROBP, 2009

153 rectal cancer patients 3-field EBRT with concomitant chemotherapy 21 % acute G3 diarrhea

175 prostate cancer patients 3D CRT or IMRT 12% acute Gr 2-3 bowel toxicity

Robertson IJROBP, 201

Impact of V15 on diarrhea seemed strongest V15 should however be seen as a geometrical surrogate for the high dose volumes and not used alone for optimizing IMRT dose distribution

Incidence of toxicity drops from 21% to 3% when:

V40 < 170 cc V45 < 100 cc V50 < 33 cc