Current Status of MRI and PET in the NCCN Guidelines for Prostate Cancer

Abstract

Prostate cancer (PCa) represents a significant source of morbidity and mortality for men in the United States, with approximately 1 in 9 being diagnosed with PCa in their lifetime. The role of imaging in the evaluation of men with PCa has evolved and currently plays a central role in diagnosis, treatment planning, and evaluation of recurrence. Appropriate use of multiparametric MRI (mpMRI) and MRI-guided transrectal ultrasound (MR-TRUS) biopsy increases the detection of clinically significant PCa while decreasing the detection of clinically insignificant PCa. This process may help patients with clinically insignificant PCa avoid the adverse effects of unnecessary therapy. In the setting of a known PCa, patients with low-grade disease can be observed using active surveillance, which often includes a combination of prostate-specific antigen (PSA) testing, serial mpMRI, and, if indicated, follow-up systematic and targeted TRUS-guided tissue sampling. mpMRI can provide important information in the posttreatment setting, but PET/CT is creating a paradigm shift in imaging standards for patients with locally recurrent and metastatic PCa. This article examines the strengths and limitations of mpMRI for initial PCa diagnosis, active surveillance, recurrent disease evaluation, and image-guided biopsies, and the use of PET/CT imaging in men with recurrent PCa. The goal of this review is to provide a rational basis for current NCCN Clinical Practice Guidelines in Oncology for PCa as they pertain to the use of these advanced imaging modalities.

Anatomy and Imaging of Rat Prostate: Practical Monitoring in Experimental Cancer-Induced Protocols

“…However, this common PET/CT radiotracer showed limitations in detection of primary prostate cancer, due to the low glucose metabolic rate and proximity of urinary excretion [37,39]. Some recent studies using specific radiotracers without glucose, as 11 C-choline, 18F-fluciclovine, prostate-specific membrane antigen (PSMA) and 18F-sodium fluoride, had promising results, distinguishing areas of prostatic cancer from normal tissue, as well as evaluating bone metastasis [34,40,41]. PET-CT evaluation results in more accurate assessment of patients with recurrent high PSA serum levels and overcome many limitations of other medical imaging modalities [42].…”

“…PET-CT evaluation results in more accurate assessment of patients with recurrent high PSA serum levels and overcome many limitations of other medical imaging modalities [42]. 11 C-choline targets cell membrane lipids biosynthesis enhanced in cancer cells [40]. 18F-fluciclovine is an amino acid analog with an enhanced uptake in cancer cells [40].…”

“…11 C-choline targets cell membrane lipids biosynthesis enhanced in cancer cells [40]. 18F-fluciclovine is an amino acid analog with an enhanced uptake in cancer cells [40]. PSMA is normally expressed in epithelial cells within the prostate and several PSMA ligands are commercially available as Gallium-68, Fluorine-18 and Copper-64 [43].…”

How else can we approach prostate cancer biomarker discovery?

“…It is used for multiple indications including stratification of patients into low, intermediate, and high-risk groups that guide treatment regimens from active surveillance to radical prostatectomy. Although an important step forward, inherent limitations with the use of MR in the detection of clinically significant cancer are still present and contribute to both false positives and false negatives [2]. Therefore, optimizing tissue biomarker discovery that can be used as 'ground truth' for further optimization of clinical imaging protocols represents a significant unmet need in the field.…”

In vivodeuterated water labeling allows tumor visualization via deuterium magnetic resonance spectroscopic imaging of cholesterol

“…Positron emission tomography and computer tomography (PET-CT) scans are commonly used in this setting. They provide clinically valuable information that can guide therapeutic decisions [1][2][3] . Radioactive tracers, such as 18 fluorodeoxyglucose (FDG), in combination with CT take advantage of unique features of cancer cells such as their highly proliferative and glycolytic nature, allowing identification of small tumors that are not detectable by anatomical imaging alone 4 .…”