Pattern of occult nodal relapse diagnosed with 18F-fluoro-choline PET/CT in prostate cancer patients with biochemical failure after prostate-only radiotherapy

3D mapping of nodal relapses evaluated with FCH PET/CT suggests that with IMRT the upper field limit of pelvic radiotherapy could be extended to L2-L3 safely to cover 95% of nodal stations at risk of an occult relapse.