18F-Sodium fluoride uptake associated with prostate cancer patient characteristics and treatments

1652 Introduction: Plaque microcalcification is associated with atherosclerosis. Microcalcification can increase the potential for the rupture that causes cardiovascular events, even in asymptomatic individuals. Numerous recent studies have shown that 18F-Sodium Fluoride (NaF) can be used to detect calcified micro-deposits within coronary plaque [1-6]. Studies using NaF to detect microcalcification have been shown to be repeatable and reproducible [7]. Cardiovascular disease can contribute to the progression of prostate cancer [8]. Studies also have shown prostate cancer increases incidences of heart disease, with heart disease being the most common cause of death for prostate cancer survivors [9]. The goal of this study was to examine the association between coronary microcalcification assessed by NaF PET/CT as a risk factor for cardiovascular events and clinical factors in prostate cancer patients. Methods: We conducted a retrospective study of existing clinical data from 112 male patients (ages 53-91 years, mean age 71.0 years, mean BMI 29.2 kg/m2) with a history of prostate cancer from our institution’s healthcare system. Demographic and cancer therapy information were obtained from electronic medical records. The patients had all undergone (18F) NaF-PET/CT scans. Image analysis was then conducted on each of these scans through the program FIJI (ImageJ). The analysis regions were selected on CT images by drawing regions of interest around the entire heart using a semi-automatic segmentation method [6]. These regions of interests were overlaid onto the registered PET images to calculate the mean and maximum standardized uptake values (SUVs). This method was reliable with an inter-operator reproducibility of 1.9% for the correlation of variation. SUVmean and SUVmax were then correlated against patient demographics including cardiovascular risk factors, as well as different cancer treatment methods. Results: Our data revealed correlations between radiation, history of atrial fibrillation, and systolic blood pressure with uptake value of NaF. Patients who had undergone radiation had a significantly lower SUVmax than those who had not (p= 0.0107). When stratified by whether a patient had received chemotherapy in addition to radiation, those who had received both treatments had a an even more significant decrease in SUVmax (p= 0.0027), while those who had not received chemotherapy as well did not have a significant difference in SUVmax. Additionally, patients with a history of atrial fibrillation had a significantly higher SUVmean (p= 0.0153). Systolic blood pressure correlated with SUVmax (p= 0.0190). Conclusions: Our data further contributed to the body of research showing NaF uptake as a reliable indicator of increased risk for atrial fibrillation. Additionally, our data showed those with radiation had a significantly decreased SUVmax, particularly those with radiation and chemotherapy. While prior studies have raised concern over the potential for radiation and hormone therapies to increase prevalence of heart disease in patients with other types of cancer, our study shows that these methods of treatment were associated with a decrease NaF PET/CT detected coronary microcalcification in prostate cancer patients. Figure 1: Patients with a history of atrial fibrillation have a significantly higher SUVmean (p = 0.0153). Figure 2: Patients who were treated with radiation have a significantly decreased SUVmax (p= 0.0083). Image 1: Image showing NaF uptake in the heart of a patient.