18F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) is accurate for high-grade prostate cancer bone staging when compared to bone scintigraphy

Introduction: In this study, we compared F-18-fluorodeoxyglucose (F-18-FDG)-positron emission tomography/computed tomography (PET/CT) and bone scintigraphy accuracies for the detection of bone metastases for primary staging in high-grade prostate cancer (PCa) patients to determine if F-18-FDG-PET/CT could be used alone as a staging modality. Methods: Men with localized high-grade PCa (n=256, Gleason 8-10, International Society of Urological Pathology [ISUP] grades 4 or 5) were imaged with bone scintigraphy and F-18-FDG-PET/CT. We compared, on a per-patient basis, the accuracy of the two imaging modalities, taking inter-modality agreement as the standard of truth (SOT). Results: F-18-FDG-PET/CT detected at least one bone metastasis in 33 patients compared to only 26 with bone scan. Of the seven falsenegative bone scintigraphies, four (57.1%) were solitary metastases (monometastatic), three (42.9%) were oligometastatic (2-4 lesions), and none were plurimetastatic (>4 lesions). Compared to SOT, F-18-FDG-PET/CT showed higher sensitivity and accuracy than bone scintigraphy (100% vs. 78.8%, and 98.7% vs. 98.2%) for the detection of skeletal lesions. Conclusions: F-18-FDG-PET/CT appears similar or better than conventional bone scans to assess for bone metastases in patients newly diagnosed with high-grade PCa. Since intraprostatic FDG uptake is also a biomarker for failure of radical prostatectomy and that FDG-PET/CT has been shown to be accurate in detecting PCa lymph node metastasis, FDG-PET/CT has the potential to be used as the sole preoperative staging modality in high-grade PCa.

Automated summary

In this study, F-18-FDG-PET/CT was compared to bone scintigraphy for bone metastases detection in high-grade prostate cancer patients, showing higher sensitivity and accuracy. The results suggest that F-18-FDG-PET/CT could potentially be used alone as a staging modality in high-grade PCa patients.