Positron emission tomography (PET) is an imaging procedure that is unique by virtue of its ability to image biochemical reactions and physiological functions. This is accomplished by measuring concentrations of radioactive chemicals that are partially metabolized in the body region of interest.
PET with fluorodeoxyglucose (FDG) has been quite successful in the imaging evaluation of a large number of tumor types. Prostate cancer, however, has variable accumulation of FDG, which is probably a reflection of the heterogeneous nature of the disease. Early studies of FDG-PET in prostate cancer have shown that FDG accumulation in the primary prostate cancer may be low and overlap with the uptake in benign prostatic hyperplasia, in normal gland, and in postoperative scar or local recurrence. Therefore other radiopharamceutical have been tested. Among them is choline. The utility of 11C-choline and multimodality fusion imaging with integrated PET and contrast-enhanced CT (PET/CT) has been extensively investigated.
A 2009 study of 190 patients found that whole body PET/CT imaging with choline is significantly better than conventional imaging technologies in detecting prostate cancer in patients with biochemical relapse after radical prostatectomy. Researchers also found a strong association between PET/CT detection of recurrent cancer, PSA levels, and PSA kinetics. The authors suggest that based on the results, only patients with a high probability of having a positive scan based on PSA levels and kinetics should undergo choline PET/CT scans. A recent guideline (Jaffri et al) says that the technique requires more study. A 2010 study says that: “Further studies will be needed to decipher the full prognostic utility of the dynamic pattern of osseous metastatic disease from prostate cancer.” Greco in 2008 wrote: “role of PET imaging in prostate cancer is gradually evolving but still remains within the experimental realm. Well-conducted studies comparing the merits of different tracers are needed.” However, a 2013 Europaen review concluded that . In staging of patients with proven but untreated, high-risk PCa, there is limited but promising evidence warranting further studies. However, the current evidence shows crucial limitations in terms of its applicability in common clinical scenarios.
More recently, voices to defend the use of FDG PET have been raised, see Hussein et al referenced below.
Hussein Jadvar et al, FDG PET in Prostate cancer, PET Clin. 2009 April 1; 4(2): 155–161.
Morris NJ, Akhurst T, Osman I, et al. Fluorinated deoxyglucose positron emission tomography imaging in progressive metastatic prostate cancer. Urology. 2002;59:913-918. A
P. Castellucci, C. Fuccio, C. Nanni, I. Santi, A. Rizzello, F. Lodi, A. Franceshelli, G. Martorana, F. Manferrari, and S. Fanti, S. Sharp, B. Shulkin, M. Gelfand, S. Salisbury, W. Furman, Nuclear Medicine Unit, Hematology-Oncology and Laboratory Medicine Department, and Urology Unit, Specialist Surgery and Anaesthesiology Department, Azienda Ospedaliero-Universitaria di Bologna Policlinico S. Orsola-Malpghi, University of Bologna, Italy; “Influence of Trigger PSA and PSA Kenetics on 11C-Choline PET/CT Detection Rate in Patients with Biochemical Relapse After Radical Prostatectomy,” The Journal of Nuclear Medicine, September 2009.
Beheshti M, Vali R, Waldenberger P, et al The Use of F-18 Choline PET in the Assessment of Bone Metastases in Prostate Cancer: Correlation With Morphological Changes on CT
Mol Imaging Biol. 2009;11:446-454
Greco C, Cascini GL, Tamburrini O. Is there a role for positron emission tomography imaging in the early evaluation of prostate cancer relapse? Prostate Cancer Prostatic Dis. 2008;11(2):121-128.