Prospective Comparison of 99mTc-MDP Scintigraphy, Combined 18F-NaF and 18F-FDG PET/CT, and Whole-Body MRI in Patients with Breast and Prostate Cancer.

UNLABELLED: We prospectively evaluated the use of combined (18)F-NaF/(18)F-FDG PET/CT in patients with breast and prostate cancer and compared the results with those for (99m)Tc-MDP bone scintigraphy and whole-body MRI. METHODS: Thirty patients (15 women with breast cancer and 15 men with prostate cancer) referred for standard-of-care bone scintigraphy were prospectively enrolled in this study. (18)F-NaF/(18)F-FDG PET/CT and whole-body MRI were performed after bone scintigraphy. The whole-body MRI protocol consisted of both unenhanced and contrast-enhanced sequences. Lesions detected with each test were tabulated, and the results were compared. RESULTS: For extraskeletal lesions, (18)F-NaF/(18)F-FDG PET/CT and whole-body MRI had no statistically significant differences in sensitivity (92.9% vs. 92.9%, P = 1.00), positive predictive value (81.3% vs. 86.7%, P = 0.68), or accuracy (76.5% vs. 82.4%, P = 0.56). However, (18)F-NaF/(18)F-FDG PET/CT showed significantly higher sensitivity and accuracy than whole-body MRI (96.2% vs. 81.4%, P < 0.001, 89.8% vs. 74.7%, P = 0.01) and bone scintigraphy (96.2% vs. 64.6%, P < 0.001, 89.8% vs. 65.9%, P < 0.001) for the detection of skeletal lesions. Overall, (18)F-NaF/(18)F-FDG PET/CT showed higher sensitivity and accuracy than whole-body MRI (95.7% vs. 83.3%, P < 0.002, 87.6% vs. 76.0%, P < 0.02) but not statistically significantly so when compared with a combination of whole-body MRI and bone scintigraphy (95.7% vs. 91.6%, P = 0.17, 87.6% vs. 83.0%, P = 0.53). (18)F-NaF/(18)F-FDG PET/CT showed no significant difference from a combination of (18)F-NaF/(18)F-FDG PET/CT and whole-body MRI. No statistically significant differences in positive predictive value were noted among the 3 examinations. CONCLUSION: (18)F-NaF/(18)F-FDG PET/CT is superior to whole-body MRI and (99m)Tc-MDP scintigraphy for evaluation of skeletal disease extent. Further, (18)F-NaF/(18)F-FDG PET/CT and whole-body MRI detected extraskeletal disease that may change the management of these patients. (18)F-NaF/(18)F-FDG PET/CT provides diagnostic ability similar to that of a combination of whole-body MRI and bone scintigraphy in patients with breast and prostate cancer. Larger cohorts are needed to confirm these preliminary findings, ideally using the newly introduced simultaneous PET/MRI scanners.

Detection of osseous metastasis by 18F-NaF/18F-FDG PET/CT versus CT alone.

PURPOSE: Sodium fluoride PET (18F-NaF) has recently reemerged as a valuable method for detection of osseous metastasis, with recent work highlighting the potential of coadministered 18F-NaF and 18F-FDG PET/CT in a single combined imaging examination. We further examined the potential of such combined examinations by comparing dual tracer 18F-NaF18/F-FDG PET/CT with CT alone for detection of osseous metastasis. PATIENTS AND METHODS: Seventy-five participants with biopsy-proven malignancy were consecutively enrolled from a single center and underwent combined 18F-NaF/18F-FDG PET/CT and diagnostic CT scans. PET/CT as well as CT only images were reviewed in blinded fashion and compared with the results of clinical, imaging, or histological follow-up as a truth standard. RESULTS: Sensitivity of the combined 18F-NaF/18F-FDG PET/CT was higher than that of CT alone (97.4% vs 66.7%). CT and 18F-NaF/18F-FDG PET/CT were concordant in 73% of studies. Of 20 discordant cases, 18F-NaF/18F-FDG PET/CT was correct in 19 (95%). Three cases were interpreted concordantly but incorrectly, and all 3 were false positives. A single case of osseous metastasis was detected by CT alone, but not by 18F-NaF/18F-FDG PET/CT. CONCLUSIONS: Combined 18F-NaF/18F-FDG PET/CT outperforms CT alone and is highly sensitive and specific for detection of osseous metastases. The concordantly interpreted false-positive cases demonstrate the difficulty of distinguishing degenerative from malignant disease, whereas the single case of metastasis seen on CT but not PET highlights the need for careful review of CT images in multimodality studies.

Semiquantitative Analysis of the Biodistribution of the Combined ¹8F-NaF and ¹8F-FDG Administration for PET/CT Imaging.

UNLABELLED: In this study, we evaluated the biodistribution of the (18)F(-)/(18)F-FDG administration, compared with separate (18)F-NaF and (18)F-FDG administrations. We also estimated the interaction of (18)F-NaF and (18)F-FDG in the (18)F(-)/(18)F-FDG administration by semiquantitative analysis. METHODS: We retrospectively analyzed the data of 49 patients (39 men, 10 women; mean age ± SD, 59.3 ± 15.2 y) who underwent separate (18)F-FDG PET/CT and (18)F-NaF PET/CT scans as well as (18)F(-)/(18)F-FDG PET/CT sequentially. The most common primary diagnosis was prostate cancer (n = 28), followed by sarcoma (n = 9) and breast cancer (n = 6). The mean standardized uptake values (SUVs) were recorded for 18 organs in all patients, and maximum SUV and mean SUV were recorded for all the identified malignant lesions. We also estimated the (18)F(-)/(18)F-FDG uptake as the sum of (18)F-FDG uptake and adjusted (18)F-NaF uptake based on the ratio of (18)F-NaF injected dose in (18)F(-)/(18)F-FDG PET/CT. Lastly, we compared the results to explore the interaction of (18)F-FDG and (18)F-NaF uptake in the (18)F(-)/(18)F-FDG scan. RESULTS: The (18)F(-)/(18)F-FDG uptake in the cerebral cortex, cerebellum, parotid grand, myocardium, and bowel mostly reflected the (18)F-FDG uptake, whereas the uptake in the other analyzed structures was influenced by both the (18)F-FDG and the (18)F-NaF uptake. The (18)F(-)/(18)F-FDG uptake in extraskeletal lesions showed no significant difference when compared with the uptake from the separate (18)F-FDG scan. The (18)F(-)/(18)F-FDG uptake in skeletal lesions reflected mostly the (18)F-NaF uptake. The tumor-to-background ratio of (18)F(-)/(18)F-FDG in extraskeletal lesions showed no significant difference when compared with that from (18)F-FDG alone (P = 0.73). For skeletal lesions, the tumor-to-background ratio of (18)F(-)/(18)F-FDG was lower than that from (18)F-NaF alone (P < 0.001); however, this difference did not result in missed skeletal lesions on the (18)F(-)/(18)F-FDG scan. CONCLUSION: The understanding of the biodistribution of radiopharmaceuticals and the lesion uptake of the (18)F(-)/(18)F-FDG scan as well as the variations compared with the uptake on the separate (18)F-FDG PET/CT and (18)F-NaF PET/CT are valuable for more in-depth evaluation of the combined scanning technique.

Combined 18F-NaF and 18F-FDG PET/CT in the Evaluation of Sarcoma Patients.

PURPOSE: The combined administration of F-NaF and F-FDG in a single PET/CT scan has the potential to improve patient convenience and cancer detection. Here we report the use of this approach for patients with sarcomas. PATIENTS AND METHODS: This is a retrospective review of 21 patients (12 men, 9 women; age, 19-66 years) with biopsy-proven sarcomas who had separate F-NaF PET/CT, F-FDG PET/CT, and combined F-NaF/F-FDG PET/CT scans for evaluation of malignancy. Two board-certified nuclear medicine physicians and 1 board-certified musculoskeletal radiologist were randomly assigned to review the scans. Results were analyzed for sensitivity and specificity, using linear regression and receiver operating characteristics. RESULTS: A total of 13 patients had metastatic disease on F-NaF PET/CT, F-FDG PET/CT, and combined F-NaF/F-FDG PET/CT. Skeletal disease was more extensive on the F-NaF PET/CT scan than on the F-FDG PET/CT in 3 patients, whereas in 1 patient, F-FDG PET/CT showed skeletal disease and the F-NaF PET/CT was negative. Extraskeletal lesions were detected on both F-FDG and combined F-NaF/F-FDG PET/CT in 20 patients, with 1 discordant finding in the lung. CONCLUSIONS: The combined F-NaF/F-FDG PET/CT scan allows for accurate evaluation of sarcoma patients. Further evaluation of this proposed imaging modality is warranted to identify the most suitable clinical scenarios, including initial treatment strategy and evaluation of response to therapy.

18F-sodium fluoride PET/CT in oncology: an atlas of SUVs.

PURPOSE: The purpose of this study was to analyze the distribution of 18F Sodium Fluoride (18F-NaF) uptake in the normal skeleton, benign and malignant bone lesions, and extraskeletal tissues, using semiquantitative SUV measurements. PATIENTS AND METHODS: We retrospectively analyzed data from 129 patients who had 18F-NaF PET/CT at our institution for an oncological diagnosis between 2007 and 2014. There were 99 men and 30 women, 19 to 90 years old (mean [SD], 61.5 [15.5]). The range, average, and SD of SUV were measured for normal bone and extraskeletal tissues uptake for the entire patient population. A separate statistical analysis was performed to compare group A, which corresponds to the population of patient with no 18F-NaF-avid metastatic lesions, and group B, which corresponds to the population of patient with 18F-NaF-avid metastatic lesions. We also measured SUV max and SUV mean for bony metastases and degenerative changes RESULTS: The PET/CT images were acquired at 30 to 169 minutes (mean [SD], 76.5 [22.8]) after injection of 3.9 to 13.6 mCi (mean [SD], 7.3 [2.4]) of 18F-NaF. The range and mean (SD) of SUV max for 18F-NaF-avid metastasis were 4.5 to 103.3 and 25.9 (16.6) and for 18F-NaF-avid degenerative changes were 3.3 to 52.1 and 16.5 (7.9), respectively. CONCLUSIONS: Various skeletal sites have different normal SUVs. Skeletal metastases have different SUVs when compared with benign findings such as degenerative changes.