Spine metastases in prostate cancer: comparison of technetium‐99m‐MDP whole‐body bone scintigraphy, [¹⁸F]choline positron emission tomography(PET)/computed tomography (CT) and [¹⁸F]NaF PET/CT

Abstract

ObjectiveTo compare the diagnostic accuracy of the following imaging techniques in the detection of spine metastases, using magnetic resonance imaging (MRI) as a reference: whole-body bone scintigraphy (WBS) with technetium-99m-MDP, [18F]-sodium fluoride (NaF) positron emission tomography (PET)/computed tomography (CT) and [ Patients and MethodsThe study entry criteria were biopsy-proven prostate cancer, a positive WBS consistent with bone metastases, and no history of androgen deprivation. Within 30 days of informed consent, trial scans were performed in random order. Scans were interpreted blindly for the purpose of a lesion-based analysis. The primary target variable was bone lesion (malignant/ benign) and the 'gold standard' was MRI. ResultsA total of 50 men were recruited between May 2009 and March 2012. Their mean age was 73 years, their median PSA level was 84 ng/mL, and the mean Gleason score of the tumours was 7.7. A total of 46 patients underwent all four scans, while four missed one PET/CT scan. A total of 526 bone lesions were found in the 50 men: 363 malignant and 163 non-malignant according to MRI. Sensitivity, specificity, positive and negative predictive values and accuracy were: WBS: 51, 82, 86, 43 and 61%; 54, 82, 78 and 81%; 91, 95, 75 and 87%, respectively. ConclusionsWe found that FCH-PET/CT and NaF-PET/CT were superior to WBS with regard to detection of prostate cancer bone metastases within the spine. The present results call into question the use of WBS as the method of choice in patients with hormone-naïve prostate cancer.

Evaluation of Prostate Cancer Bone Metastases with 18F-NaF and 18F-Fluorocholine PET/CT

“…Review of the correlated sensitivity and specificity of 18 F-NaF PET/CT in the medical literature shows varying results. Although Even-Sapir et al (35) calculated a sensitivity and specificity of 100%, Poulsen et al (36) reported a sensitivity of 93% and an unexpected specificity of 54%, most likely because of the high number of falsepositive lesions associated with degenerative or inflammatory changes in older patients, who made up the population of that study.…”

“…In a comparative study by EvenSapir et al (35), the calculated sensitivity and specificity for planar bone scintigraphy were 70% and 57%, respectively, compared with 100% and 100% for 18 F-NaF PET/CT. However, because of the mechanism of action and uptake, and because of nonspecific characteristics, increased uptake is seen in degenerative changes (36). Therefore, one of the key points in the interpretation of 18 FNaF PET/CT studies is to consider this issue, correlate the PET findings with morphologic changes on CT, and ascertain that the uptake is not associated with the end plates or joint surfaces.…”

Evaluation of Prostate Cancer with 11C- and 18F-Choline PET/CT: Diagnosis and Initial Staging

“…18 F-choline PET/CT changed the stage in 33.3% of the patients (36). In a prospective study on the accuracy of various imaging modalities for the detection of spine metastases, Poulsen et al reported that 18 F-choline PET/CT had a higher specificity than BS and 18 F-fluoride PET/CT (91% vs. 82% and 54%) and that the sensitivity of 18 F-choline PET/CT was higher than that of BS but lower than that of 18 F-fluoride PET/CT (85% vs. 51% and 93%) (45). In their recently published review, De Bari et al concluded that 11 C-or 18 F-choline PET had a better sensitivity during the early progression of bone metastases, when they were still located in the bone marrow (27).…”

Superioridade da PET/CT com FNa-F18 na Deteção de Metástases Ósseas quando Comparada com Outros Métodos de Diagnóstico por Imagem

“…16,17 Apresenta elevada especificidade porque a CT da PET/CT, ao caracterizar morfologicamente as alterações funcionais, contribui para a diferenciação entre lesões benignas e metástases ósseas. 10 Permite, assim, otimizar o estadiamento, selecionar a melhor estraté-gia terapêutica na altura mais adequada 18 e é mais eficaz na avaliação da resposta ao tratamento instituído, 19 tendo superior impacto na abordagem dos doentes oncológicos com metástases ósseas. 20,21 Na nossa experiência, a PET/CT com FNa-F18 também apresentou maior capacidade de deteção que a CO (em 49% dos casos) e fê-lo de um modo mais assertivo, necessitando de exames complementares para melhor esclarecimento num número muito menor de doentes (3,5% vs 45%).…”

“…As guidelines atuais continuam a incluir a CO como o método imagiológico a utilizar mas, cada vez mais, a literatura disponível enfatiza a superior capacidade de deteção da PET/CT com FNa-F18. 20,31 Com a difusão dos equipamentos de PET/CT e a otimização da logística de distribuição do FNa-F18, é previsível que este exame venha a substituir a CO, na prática clínica, não só nos doentes oncológicos 18 como, também, nas patologias esqueléticas benignas.…”