Target Volume Determination 2015

How do we define the CTV?

The clinical target volume (CTV)

“Delineating the CTV is more an art than a science because current imaging techniques are not capable of detecting subclinical tumor involvement directly”. Perez & Brady, 2008 Defining the CTV: 1. Probability of microscopic tumor extension: 5-10%. 2. Methods: • Volumetric (isotropic) expansion using margins. • Anatomic/compartmental: including anatomic compartments bounded by anatomic barriers.

Perez & Brady. In: Principles and practice of radiation oncology. Lippincott Williams & Wilkins. 2008:228. ICRU report 83 . 2010;10:44-45.