Figure 6.

Example of 56 year-old woman with T4N2M0 oropharyngeal squamous cell carcinoma. A therapeutic response assessment by PET/CT was performed 3 months after chemo-radiotherapy, showing persistent disease. PET_A (images on the top) and PET_R (images on the bottom) were scanned in treatment position (TP) and coregistered with RR method (left) and ER method (right). A₄₀ subvolume is represented as a yellow line, R₄₀ subvolume as a blue line and A₄₀∩R₄₀ in red area. The OF (A₄₀, R₄₀) index was calculated, respectively at 0.50 and 0.51 for RR and ER registration methods.