Getting the Most out of 18F-FDG PET Scans: The Predictive Value of 18F-FDG PET-Derived Blood Flow Estimates for Breast Cancer.

Abstract

1667 Objectives The need for serological biomarkers to identify vulnerable patients with active atherosclerosis is increasingly emphasized. Autoantibodies against MYC-associated zinc finger protein (MAZI) have recently been identified in patients with acute myocardial infarction. In this study, we assessed the utility of anti-MAZI antibodies for identifying atherosclerosis in terms of calcified plaque burden and plaque inflammation as determined by 18F-FDG PET/CT. Methods One hundred patients (57 women, 43 men; mean age±SD, 47.6±13.1 y; range, 15.7±65.0 y) undergoing 18F-FDG PET/CT for non-cardiovascular indications were prospectively enrolled. Blood samples were taken at the time of PET/CT to identify anti-MAZI antibodies by enzyme-linked immunosorbent assay (ELISA). Clinical risk factors were recorded. FDG uptake in various arterial segments was analyzed by measuring blood-pool-corrected standardized uptake values (target-to-background ratio, TBR), and compared with calcified plaque burden. Results Focal arterial uptake of 18F-FDG was seen at 1623 sites in 100% of patients. Calcified atherosclerotic lesions were detected at 4141 sites in 65.0% of patients. Significant anti-MAZI antibody titers were observed in 24% of patients. The presence of anti-MAZI antibodies was significantly associated with a history of prior myocardial infarction (n=5, p=0.01). The extent of atherosclerosis as determined by CT was significantly higher in patients with positive anti-MAZI antibodies, i.e. calcified plaque burden (p=0.03) and maximum diameter of calcified plaques (p=0.01) were more frequently found. Compared to the rest of the study population, PET-based inflammatory activity of plaque, i.e. number of arterial uptake foci and TBR (p>0.05), was not significantly higher in patients with positive anti-MAZI antibodies. Conclusions Anti-MAZI antibodies are significantly more frequent in patients with a history of myocardial infarction. While anti-MAZI antibodies are not associated with PET-derived inflammatory activity of plaque, they may be linked to calcified, more advanced stages of atherosclerotic disease. $$graphic_011348B8-6541-4E2C-A023-419B4C1686CD$$