Inclusion Criteria:

group 1

1. Patient must have a diagnosis of prostate cancer confirmed by pathology.

2. Patient must be scheduled to undergo radical prostatectomy no sooner than 6 weeks
from date of enrollment (to allow for a minimum of 4 weeks on the low protein diet).

3. Patient must have adequate baseline protein intake (screening 4-day food record shows
protein > 1.0 g/kg FFM)

4. Patient must be able to understand the English-language instructions.

5. Patient must be able to comply with the low protein diet (as evaluated by the
dietitian and other study team members).

6. Patient must be able to understand and willing to sign an IRB-approved written
informed consent document.

5.2.2 Inclusion Criteria - Group 2

1. Patient must have a diagnosis of prostate cancer.

2. Patient must have previously undergone a radical prostatectomy for treatment of
prostate cancer.

3. Patient must have a detectable PSA (defined as PSA ≥ 0.1) in at least two consecutive
measurements, taken at least one month apart, with no therapy between the PSA
measurements. If the patient has had additional therapy after the radical
prostatectomy, there must be evidence of a rising PSA (i.e., two consecutive
measurements at least one month apart) after the patient has completed the
intervening therapy (meaning that the patient must have failed treatment).

4. Patient must have adequate baseline protein intake (screening 4-day food record shows
protein > 1.0 g/kg FFM).

5. Patient must have adequate baseline caloric intake (screening 4-day food record shows
caloric intake of > 1500 kcal/day).

6. Patient must be able to understand the English-language instructions.

7. Patient must be able to comply with the low protein diet (as evaluated by the
dietitian and other study team members).

8. Patient must be able to understand and willing to sign an IRB-approved written
informed consent document.

Exclusion Criteria:

1. Patient must not currently be receiving any therapy for prostate cancer.

2. Patient must not have any serious chronic illness such as unstable angina, any
uncontrolled metabolic disorder, or any immunologic disorder.

3. Patient must not have a history of any previous malignancy (with the exception of
squamous or basal cell carcinoma of the skin) in the 5 years prior to enrollment (for
Group 1) or 12 months prior to enrollment (for Group 2).

4. Patient must not have a previous history of a stroke.

5. Patient must not be taking any medications that might confound the study results
(anabolic agents (such as androgen, androgen precursor, rhGH) in the 6 months prior
to enrollment; corticosteroids (other than nasal) in the 6 months prior to
enrollment; or finasteride or dutasteride).

6. Patient must not have dementia or any other cognitive impairment.

7. Patient must not have a lifestyle or fixed diet pattern that would interfere with
participation in or interpretation of the results of this study

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