Utility of FDG‐PET in clinical neuroendocrine prostate cancer

Abstract

BACKGROUND Fluorodeoxyglucose (FDG) positron emission tomography (PET) has well-characterized limitations in prostate adenocarcinoma (PCA). However, data assessing the utility of PET in neuroendocrine prostate cancer (NEPC) is limited to isolated case reports. Herein, we describe the first case series to assess the utility of FDG-PET in NEPC. METHODS Inclusion criteria consisted of clinically progressive metastatic PCA in the setting of a chromogranin-A levels >1.5x the upper limit of normal, and ≥1 FDG-PET scan after the diagnosis of NEPC, which yielded 23 patients. All metastatic lesions on CT, PET, and bone scan were read by two independent physicians. RESULTS Five hundred ninety two unique lesions were identified across all imaging modalities, 510 were bone metastases, and 82 were soft tissue metastases. Of bone lesions, 22.2%, 92.7%, and 77.6% were detected by PET, CT, and bone scan, respectively. Of soft tissue lesions, 95.1% and 97.5% were detected by PET and CT, respectively. Stratified by the median survival from NEPC diagnosis, patients who survived <2.2 versus ≥2.2 years had more PET avid bone (8 vs. 2, P=0.06) and soft tissue lesions (7 vs. 1, P=0.01), and higher average SUVmax of bone (5.49 vs. 3.40, P=0.04) and soft tissue lesions (8.02 vs. 3.90, P=0.0002). CONCLUSIONS In patients with clinical NEPC, we demonstrate that FDG-PET has clinical utility in the detection of metastatic disease. In addition to detection, PET allows for treatment response to determine tumor viability. With novel therapies on the horizon to treat NEPC, consideration to investigate the use of FDG-PET to monitor response is warranted.

Proteogenomic Characterization of Patient-Derived Xenografts Highlights the Role of REST in Neuroendocrine Differentiation of Castration-Resistant Prostate Cancer

“…This conclusion is supported by studies using fluorodeoxyglucose (FDG) positron emission tomography (PET) in patients with suspected neuroendocrine tumors. Visceral metastases, the preferred site for NEPCs, show higher uptake of FDG as when compared to bone metastases, the preferred site for AR-expressing castration-resistant adenocarcinomas (47).…”

Prostate cancer–specific PET radiotracers: A review on the clinical utility in recurrent disease

“…These include C-11 acetate and F-18 sodium fluoride. In addition, F-18 PET may be useful in imaging prostate cancer patients who have developed dedifferentiated neuroendocrine tumors of the prostate, 55 which conversely may not image well using these pcPET agents.…”

Imaging Somatostatin Receptor Activity in Neuroendocrine-differentiated Prostate Cancer

“…Imaging using 18-fluorodeoxyglucose positron emission tomography ( 18 F-FDG-PET) can help detect NEPC lesions ( 6 ). Prostate adenocarcinoma and prostatomegaly take up similar amounts of FDG.…”

“…By specifically targeting lesions with somatostatin receptors, SRS imaging using 111 In-pentetreotide might help to identify metastatic NEPC lesions. In fact, SRS using 111 In-pentetreotide can detect primary and metastatic lesions more effectively than FDG-PET ( 6 - 8 ).…”