Brief Summary: RATIONALE: Gathering information about genetic and environmental factors may help doctors learn more about a person's risk for developing prostate cancer. PURPOSE: This research project is studying genes, environment, and prostate cancer risk in patients with or without prostate cancer.

Detailed Description: OBJECTIVES: * To determine the association between variation in genes involved in ROS detoxification, oxidative stress response, and prostate cancer risk. * To determine the association between fatty acid levels and prostate cancer risk. OUTLINE: Probands undergo blood and saliva sample collection for fatty acid, DNA, and polymorphism analyses. Archived blood and tissue samples from probands who previously participated in Dr. Shannon's Diet and Prostate Cancer Risk study are also analyzed. Medical records of probands are reviewed for demographics, history and course of disease, and clinical laboratory test results. All probands completed the "Genetic Risk Easy Assessment Tool Family History of Cancer" and "Diet History and Environmental Risk Factor" questionnaires at baseline. If a proband previously participated on our Diet and Prostate Cancer Risk study, he was asked to complete the "Changes in Diet, Prescriptions, Supplementals and Herbal Remedies" questionnaire in addition to the "Genetic Risk Easy Assessment Tool Family History of Cancer" questionnaire at baseline for this study. PROJECTED ACCRUAL: A total of 750 participants will be accrued for this study.