Suppression of effects of androgens with male sex hormones, androgen suppression treatment (AST), has been known to reduce deaths and prolong life in advanced prostate cancer. There have, however, been concerns raised in previous studies that androgen suppression may be associated with increased rate of heart attacks, particularly in older men. This study looks at prostate cancer patients in The Ottawa Hospital Cancer Clinic to see if treating these patients with androgen suppression is associated with a decrease in blood flow to the heart muscles by using Positron Emission Tomography (PET) and brachial artery ultrasound.

Treatment group: Prior to the initiation of AST, subjects will have a baseline N-13-ammonia PET scan and a brachial artery ultrasound at the University of Ottawa Heart Institute. Blood glucose and a lipid profile will be obtained. These tests will be repeated 6 - 9 months after starting AST.

Cancer control group: The same testing and intervals will be performed. Normals control group: Baseline testing will be done to establish a normal.

Inclusion Criteria:

Cancer Population:

1. Diagnosis of prostate cancer
2. Treatment group: Scheduled to start AST, at Ottawa Hospital under the care of Radiation Oncology, Urology or Medical Oncology.

Control group: no AST scheduled as a treatment option for prostate cancer.

Non-Cancer Control Group

1. Male with low pre-test likelihood of coronary artery disease
2. No previous history of cancer.

Exclusion Criteria:

1. Known coronary disease including any of previous revascularization, history of myocardial infarction, coronary disease with >= 50% stenosis in a major coronary vessel on previous angiography, evidence of previous myocardial infarction on 12-lead electrocardiogram, positive myocardial perfusion scan, previous cardiac PET scan, stress echocardiogram or exercise stress test.
2. Subjects with a Summed Stress Score of >4 attributed to coronary disease on baseline PET images
3. Patients previously treated with AST
4. Patients with a life expectancy of less than 1 year.