RATIONALE: Obesity and overweight are associated with the risk of aggressive disease, and energy balance may play a major role in prostate cancer progression.

PURPOSE: Randomized phase II trial to study the effectiveness of weight loss, via a healthy energy-restricted diet and exercise, in slowing or preventing disease progression in patients who have newly diagnosed prostate cancer.

This is a 2-arm randomized controlled feasibility trial among 40 overweight or obese men newly diagnosed with prostate cancer who are scheduled for prostatectomy. This study will use the presurgical period to explore the potential impact of weight loss via a healthy energy-restricted diet and increased physical activity on circulating hormones, cytokines, and growth factors, as well as effects on tumor biology and other clinical outcomes. Consenting patients will be block randomized to 1-of-2 study arms: 1) a healthful diet + exercise intervention to promote a weight loss of up to 2 pounds/week; or 2) a wait-list control who will receive the intervention once the study period is complete. Both groups will receive nutritional counseling during the study period to correct nutritional deficiencies with food sources. This study will explore and contrast changes in body mass index (BMI) observed over the study period (minimum of 3.5 weeks) in the intervention vs. wait-list control arms, and also monitor changes in body composition, energy intake and physical activity; these changes will be studied in relation to the following endpoints: a) changes in select circulating biomarkers and gene expression related to cancer progression, hormonal status, inflammation and other energy-related factors; b) rates of tumor proliferation and apoptosis; c) tumor immunohistochemical markers of insulin receptor, vascular endothelial growth factor (VEGF), AKT, and nuclear factor kappa-light-chain-enhancer of activated B cells (NFkB); and d) functional and health-related outcomes, i.e., side-effects and medical outcomes, quality of life (QoL), and functional status.

Inclusion Criteria:

• Histopathologically confirmed prostate cancer
• Elects prostatectomy as first line treatment (i.e., no androgen ablation, radiation therapy, etc)
• Has at least 3.5 weeks lag-time until scheduled prostatectomy (must be able to participate in the diet and exercise program a full 3.5 weeks).
• Body mass index (BMI) 25 - 49.9
• Mentally competent
• Able to speak and write English
• Has telephone access
• Agrees to be randomized to either study arm (immediate or delayed diet and exercise program)

Exclusion Criteria:

• Another active malignancy (not including non-melanoma skin cancer)
• Medical conditions that affect weight (e.g., untreated thyroid disturbances
• Currently on a weight loss regimen
• Preexisting medical condition(s) that preclude adherence to unsupervised exercise, e.g., severe orthopedic conditions, scheduled for a hip or knee replacement, bone metastases, paralysis, dementia, untreated stage 3 hypertension, or unstable angina, heart attack, congestive heart failure or conditions that dictated hospitalization or oxygen within 6-mths, etc.