Related Experiment Video
Updated: Jun 8, 2026
MR Molecular Imaging of Prostate Cancer with a Small Molecular CLT1 Peptide Targeted Contrast Agent
Published on: September 3, 2013
Intensity-modulated radiotherapy for prostate cancer implementing molecular imaging with 18F-choline PET-CT to define
Michael Pinkawa1, Richard Holy, Marc D Piroth
1Department of Radiotherapy, RWTH Aachen, Aachen, Germany. mpinkawa@ukaachen.de
Purpose:
To report the own experience with 66 patients who received 18F-choline PET-CT (positron emission tomography-computed tomography) for treatment planning.
Patients And Methods:
Image acquisition followed 1 h after injection of 178-355 MBq (18)F-choline. An intraprostatic lesion (GTV(PET) [gross tumor volume]) was defined by a tumor-to-background SUV (standard uptake value) ratio > 2. A dose of 76 Gy was prescribed to the prostate in 2-Gy fractions, with a simultaneous integrated boost up to 80 Gy.
Results:
A boost volume could not be defined for a single patient. One, two and three or more lesions were found for 36 (55%), 22 (33%) and seven patients (11%). The lobe(s) with a positive biopsy correlated with a GTV(PET) in the same lobe in 63 cases (97%). GTV(PET) was additionally defined in 33 of 41 prostate lobes (80%) with only negative biopsies. GTV(PET), SUV(mean) and SUV(max) were found to be dependent on well-known prognostic risk factors, particularly T-stage and Gleason Score. In multivariate analysis, Gleason Score > 7 resulted as an independent factor for GTV(PET) > 8 cm(3) (hazard ratio 5.5; p = 0.02) and SUV(max) > 5 (hazard ratio 4.4; p = 0.04). Neoadjuvant hormonal treatment (NHT) did not affect SUV levels. The mean EUDs (equivalent uniform doses) to the rectum and bladder (55.9 Gy and 54.8 Gy) were comparable to patients (n = 18) who were treated in the same period without a boost (54.3 Gy and 55.6 Gy).
Conclusion:
Treatment planning with (18)F-choline PET-CT allows the definition of an integrated boost in nearly all prostate cancer patients - including patients after NHT - without considerably affecting EUDs for the organs at risk. GTV(PET) and SUV levels were found to be dependent on prognostic risk factors, particularly Gleason Score.
