Fig. 1.

Representative oxygen partial pressure, pO₂, maps at the three different time points (before treatment: pO₂ map 1, at week 2: pO₂ map 2, and at week 5: pO₂ map 3) derived from ¹⁸FMISO PET scans are shown for a patient with non-recurrent tumour (patient 13, upper panel) and for a patient developing recurrence (patient 12, lower panel). Hypoxic target volumes (HTV, corresponding to a 10 mmHg threshold) and total Gross Tumour Volume (GTV_all, given by the union of the primary GTV and the GTV of the lymph nodes) are contoured in the images.