The MEAL study aims to study the ability of diet to alter the natural history of clinically localized, low risk prostate cancer. This study targets men diagnosed with clinically localized, low risk prostate cancer and who have already decided to be managed by active surveillance. The participants will be randomized into two groups. Each group has 232 patients. Both groups will have their prostate cancer and diet monitored the same way. The two groups will differ only in that Group A will receive 22 telephone counseling sessions to assist them with dietary change whereas Group B will not. Group B will be asked to adhere to the USDA dietary recommendations but Group A will be helped to change their diet more rigorously; they will try to increase the daily intake of vegetables, fruits, whole grain and legumes. The target daily intake of the above mentioned food groups (for Group A only) is: 7 servings of vegetables (3 cruciferous, 2 tomatoes/tomato products, 2 other vegetables), 2 servings per day of whole grain, 2 servings per day of fruit, 1 serving per day of bean or other legumes.
The principal strategy to promote dietary change in the intervention arm will be a telephone counseling protocol with individualized, one-on-one assistance tailored to each participant. The intervention will last 24 months. Intervention participants will engage in a series of telephone-based diet counseling sessions throughout the study. The first phase of sessions will guide initial diet-change attempts, the second will help participants complete their diet changes, and the third and fourth phases will enable participants to maintain and monitor their diet changes. This highly structured, computer-assisted telephone counseling protocol will facilitate standardization of the intervention.
Group A participants will receive an initial orientation phone call to describe the dietary goals of the study, it's scientific background and to introduce the "Participant Notebook". This notebook provides written material to describe the counseling program, information about dietary goals, study strategies and reference tools to estimate serving sizes. They will also receive 8 regularly scheduled newsletters by mail. The non-intervention arm (group B) patients will be given the United States Department of Agriculture "USDA" dietary guide for Americans. These patients will also receive an orientation phone call (5-10 min long) at the beginning of the study and 8 regularly scheduled newsletters by mail. Throughout the study, the patients in the two groups will be followed up regularly by clinic visitsat 3 mo, PSA blood test at 3 mo, digital rectal exam (at the urologist's discretion)at 12 mo, prostate biopsy at 12and 24 months, fasting blood samples at 12and 24 mo, phone questionnaires about health, food intake, food preparation, eating habits, function, anxiety and quality of liver every 6 months. These patients will receive 24 hour dietary recalls at 12and 24 months, over the phone. Each of these recalls is composed of a set of three separate phone calls, the participant will be asked to recall what he has eaten or drunk over the preceding 24 hour period.