Imaging evaluation of prostate cancer with 18F-fluorodeoxyglucose PET/CT: utility and limitations

Abstract

Prostate cancer poses a major public health problem in the developed countries. The remarkable biological and clinical heterogeneity of prostate cancer provides unique opportunities as well as challenges for the diagnostic imaging evaluation of this prevalent disease. The disease is characterized by a natural history that ranges from localized slowly-growing hormone-dependent tumor progressing to metastatic hormone-refractory disease. Positron emission tomography (PET) is an ideal imaging tool for noninvasive interrogation of the underlying tumor biology. Fluorine-18 fluorodeoxyglucose (FDG) is the most common PET radiotracer used for oncologic applications which is based upon elevated glucose metabolism in malignant tissue in comparison to normal tissue. FDG uptake in the prostate cancer depends on tumor differentiation with low accumulation in well-differentiated tumors and high uptake in aggressive poorly-differentiated tumors. Cumulative current evidence suggests that FDG PET may be useful in detection of disease in a small fraction of patients with biochemical recurrence, in the imaging evaluation of extent and treatment response in metastatic disease and in prediction of patient outcome.

Functional expression of sodium-glucose transporters in cancer

“…In prostate cancer, detection of neoplastic tissue in the prostate and in the pelvic lymph nodes by 2FDG-PET is hindered not only by the intrinsic low uptake of 2FDG by cancer cells but also by the imaging interference caused by the high excretion of 2FDG into the urinary bladder (15,16). Me4FDG, unlike 2FDG, is reabsorbed by the kidney, and so is not excreted into the urinary bladder (Figs.…”

“…However, 2FDG-PET does not reliably detect pancreatic and prostate cancers, and its use for diagnosis and staging is not currently recommended in clinical practice (13)(14)(15)(16). This led us to hypothesize that another class of glucose importers not detected by 2FDG, the sodium-dependent glucose transporters (SGLTs), could contribute to glucose utilization by these cancers.…”

PSMA Ligands for PET Imaging of Prostate Cancer

“…18 F-FDG is the most widely used radiotracer in oncologic PET/CT imaging; however, only a minority of PC (i.e., only aggressive, poorly differentiated, or undifferentiated PC) shows a high glycolytic rate, limiting the use of 18 F-FDG PET (7,8). In Europe, radiolabeled choline derivatives ( 18 F-fluorocholine or 11 C-choline) were among the most commonly used PET tracers for PC imaging.…”

Prostate cancer imaging

“…18 F-FDG PET/CT is limited in the detection of prostate cancer since many primary tumours are slow-growing and well differentiated, and because 18 F-FDG tumour uptake can overlap with that in normal tissue and benign prostatic hyperplasia (BPH). However, 18 F-FDG PET/CT may be useful in the detection of aggressive disease, in the evaluation of extent and treatment response in metastatic disease and in the prognostication of castrate-resistant clinical state [8].…”