White Button Mushroom Extract in Preventing the Recurrence of Breast Cancer in Postmenopausal Breast Cancer Survivors

You may be eligible if

• DISEASE CHARACTERISTICS:
• Meets 1 of the following criteria:
• * Prior diagnosis of infiltrating carcinoma of the breast ≥ 5 years prior to study entry
• * Prior diagnosis of ductal carcinoma in situ
• No evidence of disease
• Completed all cancer therapy, with the exception of reconstructive surgery, at least 6 months prior to study entry
• Meets one of the following criteria:
• * Normal mammogram within 1 year of study entry
• * Underwent bilateral mastectomy and has been in remission for 5 years, as documented by an oncologist
• Hormone receptor status not specified
• PATIENT CHARACTERISTICS:
• ECOG performance status 0-1
• WBC ≥ 3,500/mm³
• ANC ≥ 1,500/mm³
• Platelet count ≥ 100,000/mm³
• Hemoglobin ≥ 9.0 g/dL
• Postmenopausal, defined as any of the following:
• * Continuous absence of menstruation for 12+ months
• * Status post bilateral oophorectomy
• * Status post hysterectomy with follicle-stimulating hormone in menopausal range
• Creatinine ≤ 1.5 times upper limit of normal (ULN) or less
• Total bilirubin ≤ 1.5 times ULN
• AST and ALT \< 2 times ULN
• No allergy to mushrooms
• No personal history of any invasive cancer, other than breast cancer, or squamous cell or basal cell skin cancer
• No osteoporosis, defined as a bone-mineral density T-score of \< -2.5 on dual-energy x-ray absorptiometry scan
• No major systemic infections or other major medical illnesses of the cardiovascular, respiratory, or digestive system
• PRIOR CONCURRENT THERAPY:
• See Disease Characteristics
• More than 3 months since prior and no concurrent hormone-modifying medications, including any of the following:
• * Oral contraceptives
• * Hormone replacement
• * Selective estrogen receptor modifiers
• * Other aromatase inhibitors
• * Gonadotropic-releasing hormone modifiers
• At least 1 month since prior and no other concurrent mushroom extracts or DHEA as a dietary supplement
• No concurrent therapy, except continued medications for unrelated illness that are not excluded, and necessary medications for unrelated acute illnesses that may occur during the study (e.g., cold, flu, or infection)
• No more than 3 concurrent servings per week of the following foods:
• * Flaxseeds and flaxseed meal
• * High-energy bars or diet bars containing soy or soy protein
• * Liquid-nutrition drinks containing soy or soy protein (e.g., Odwalla Future Shake or Ensure Plus)
• * Miso soup
• * Natto
• * Packaged mixed dishes with soy or tofu (e.g., lasagna, burritos, or stir-fry)
• * Cooked soybeans or edamame (i.e., green soybeans)
• * Roasted soy nuts
• * Soymilk, regular or low-fat, plain or flavored
• * Soy cheese, such as cheddar, mozzarella, cram cheese, or parmesan (includes all foods made with soy cheese)
• * Soy protein powders (e.g., performance or body-builder powders)
• * Soy yogurt, all types
• * Soy sauce, tamari, teriyaki sauce, Szechuan sauce, or hoisin sauce
• * Soy ice cream, tofutti, or other soy desserts
• * Tempeh, all types
• * Tofu, all types, including low-fat, flavored, marinated, and smoked
• * Tofu or soy breakfast sausage, bacon, or other breakfast meat
• * Tofu or soy cold cuts, hot dogs, or other deli meat substitutes
• * Veggie soy or tofu burger, ground meat substitute (texturized vegetable protein), or soy or tofu, chicken, or turkey
• Concurrent supplemental calcium and/or vitamin D and bisphosphonates allowed provided doses remain constant throughout the run-in and treatment portions of the trial