Lower GI 2016

IMRT (vs 3DCRT)

- Differently from rectal ca.: larger volumes, more caudal border, (generally) higher doses, (always) concomitant to CHT, more complex shape, more concavity of PTV - 3DCRT: very large incidence of severe acute tox (mainly skin, GI, hematological) and treatment breaks - In the early 2000, several planning studies demonstrated a large gain of (sub-optimal*) IMRT vs 3DCRT (Moran 2004, Chen 2005, Milano 2005, Menkarios 2007) - Largest sparing for genitals and bowel

Milano 2005

* Few segments, manual optimization, few fields, not stressing modulation….