Shared molecular processes in comorbid atherosclerosis and cancer assessed by FDG- and NaF-PET/CT

Objectives: 1. Discuss shared features of pathophysiology such as inflammation, increased proliferation, angiogenesis, and oxidative stress in the progression of cancer and atherosclerosis. 2. Evaluate the role of FDG- and NaF-PET/CT in the evaluation of disease processes. 3. Present images of patients with comorbid atherosclerosis and prostate cancer and methods of quantifying atherosclerotic disease activity.

Methods: Tracer uptake in a vessel can be measured by manually defining a region of interest (ROI) around the vessel wall on axial PET/CT slices, and averaging the resulting SUVmean across all ROIs to determine disease activity. This process can be applied to coronary arteries, carotid arteries, thoracic aorta, and abdominal aorta using FDG to determine degree of inflammation and NaF to determine degree of calcification.

Results: In addition to assessing primary tumors and metastases, FDG- and NaF-PET/CT can detect and monitor comorbid atherosclerosis. Furthermore, varying levels of disease involvement between vessels can be observed.

Conclusions: As the relationship between cancer and atherosclerosis becomes clearer, their shared molecular characteristics can be used to assess both diseases with the same scan. FDG is often used to assess increased glycolysis by cancer cells, and NaF can portray bony changes due to skeletal metastasis. However, these tracer may play an important role in assessing comorbid atherosclerosis in these high-risk patients as techniques are further developed and validated.