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Our purpose was to establish whether noninvasive measurement of changes in 18 F-fluoride metabolic flux to bone mineral (K i ) by PET/CT can provide incremental value in response assessment of bone metastases in breast cancer compared with SUV max and SUV mean Methods: Twelve breast cancer patients starting endocrine treatment for de novo or progressive bone metastases were included. Static 18 F-fluoride PET/CT scans were acquired 60 min after injection, before and 8 wk after commencing treatment. Venous blood samples were taken at 55 and 85 min after injection to measure plasma 18 F-fluoride activity concentrations, and K i in individual bone metastases was calculated using a previously validated method. Percentage changes in K i , SUV max , and SUV mean were calculated from the same index lesions (≤5 lesions) from each patient. Clinical response up to 24 wk, assessed in consensus by 2 experienced oncologists masked to PET imaging findings, was used as a reference standard. Results: Of the 4 patients with clinically progressive disease (PD), mean K i significantly increased (>25%) in all, SUV max in 3, and SUV mean in 2. Of the 8 non-PD patients, K i decreased or remained stable in 7, SUV max in 5, and SUV mean in 6. A significant mean percentage increase from baseline for K i , compared with SUV max and SUV mean , occurred in the 4 patients with PD (89.7% vs. 41.8% and 43.5%, respectively; P < 0.001). Conclusion: After 8 wk of endocrine treatment for bone-predominant metastatic breast cancer, K i more reliably differentiated PD from non-PD than did SUV max and SUV mean , probably because measurement of SUV underestimates fluoride clearance by not considering changes in input function., (© 2019 by the Society of Nuclear Medicine and Molecular Imaging.)

Unlabelled: There is evidence in some solid tumors that textural features of tumoral uptake in (18)F-FDG PET images are associated with response to chemoradiotherapy and survival. We have investigated whether a similar relationship exists in non-small cell lung cancer (NSCLC)., Methods: Fifty-three patients (mean age, 65.8 y; 31 men, 22 women) with NSCLC treated with chemoradiotherapy underwent pretreatment (18)F-FDG PET/CT scans. Response was assessed by CT Response Evaluation Criteria in Solid Tumors (RECIST) at 12 wk. Overall survival (OS), progression-free survival (PFS), and local PFS (LPFS) were recorded. Primary tumor texture was measured by the parameters coarseness, contrast, busyness, and complexity. The following parameters were also derived from the PET data: primary tumor standardized uptake values (SUVs) (mean SUV, maximum SUV, and peak SUV), metabolic tumor volume, and total lesion glycolysis., Results: Compared with nonresponders, RECIST responders showed lower coarseness (mean, 0.012 vs. 0.027; P = 0.004) and higher contrast (mean, 0.11 vs. 0.044; P = 0.002) and busyness (mean, 0.76 vs. 0.37; P = 0.027). Neither complexity nor any of the SUV parameters predicted RECIST response. By Kaplan-Meier analysis, OS, PFS, and LPFS were lower in patients with high primary tumor coarseness (median, 21.1 mo vs. not reached, P = 0.003; 12.6 vs. 25.8 mo, P = 0.002; and 12.9 vs. 20.5 mo, P = 0.016, respectively). Tumor coarseness was an independent predictor of OS on multivariable analysis. Contrast and busyness did not show significant associations with OS (P = 0.075 and 0.059, respectively), but PFS and LPFS were longer in patients with high levels of each (for contrast: median of 20.5 vs. 12.6 mo, P = 0.015, and median not reached vs. 24 mo, P = 0.02; and for busyness: median of 20.5 vs. 12.6 mo, P = 0.01, and median not reached vs. 24 mo, P = 0.006). Neither complexity nor any of the SUV parameters showed significant associations with the survival parameters., Conclusion: In NSCLC, baseline (18)F-FDG PET scan uptake showing abnormal texture as measured by coarseness, contrast, and busyness is associated with nonresponse to chemoradiotherapy by RECIST and with poorer prognosis. Measurement of tumor metabolic heterogeneity with these parameters may provide indices that can be used to stratify patients in clinical trials for lung cancer chemoradiotherapy.