Influence of (11)C-choline PET/CT on radiotherapy planning in prostate cancer.

Aim: To evaluate the influence of C-11-choline PET/CT on radiotherapy planning in prostate cancer patients. Background: Precise information on the extension of prostate cancer is crucial for the choice of an appropriate therapeutic strategy. C-11-choline positron emission tomography (C-11-choline PET/CT) has two roles in radiation oncology (RT): (1) patient selection for treatment and (2) target volume selection and delineation. In conjunction with high-accuracy techniques, it might offer an opportunity of dose escalation and better tumour control while sparing healthy tissues. Materials and methods: We carried out a retrospective study in order to analyse RT planning modification based on C-11-choline PET/CT in 16 prostate cancer patients. Patients were treated with hypofractionated step-and-shoot Intensity Modulated Radiotherapy (IMRT), or Volumetric Modulated Arc Therapy (VMAT), and a daily cone-beam CT for Image Guided Radiation Therapy (IGRT). All patients underwent a C-11-choline-PET/CT scan prior to radiotherapy. Results: In 37.5% of cases, a re-delineation and new dose prescription occurred. Data show good preliminary clinical results in terms of biochemical control and toxicity. No gastrointestinal (GI)/genitourinary (GU) grade III toxicities were observed after a median follow-up of 9.5 months. Conclusions: In our experience, concerning the treatment of prostate cancer (PCa), C-11 choline PET/CT may be helpful in radiotherapy planning, either for dose escalation or exclusion of selected sites. (C) 2014 Greater Poland Cancer Centre. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.