Basic Treatment Planning

Volumes in ICRU50 - 1993

Clinical Target Volume (CTV) The CTV is a tissue volume that contains a demonstrable GTV and/or subclinical, microscopical malignant disease. Suspected lymph nodes Suspected disease around GTV CTV = GTV (if there) + subclinical disease

Cannot be detected - “subclinical”. Based on clinical experience.

CTV I - GTV with margin, and CTV II – lymph nodes