Particle Therapy 2017

Normal tissues

Arrangement of FSUs

parallel organization

serial organization

Spinal cord Intestine Esophagus

volume eff c : high !

functional subunit [FSU]*

FSU

volume effect: weak !

FSU

Lung Liver Kidney

FSU

FSU

* FSU = largest unit of cells that can be regenerated from a single surviving stem cell (Withers 1988)

FSU © Pearson Education, Inc. 2004

renal tubuli

inactivation of one FSU can lead to loss of organ function risk of complication strongly influenced by „hot spots“ !

functional damage: if critical number of FSU is inactivated

total dose more important than „hot spots“ !