Aerobic Exercise Training in Lowering the Risk of Breast Cancer in Patients at High-Risk for Development of Breast Cancer

Inclusion Criteria

• Women at high-risk of breast cancer, as defined by one of the following: * Cytologically confirmed atypical hyperplasia * Cytologically confirmed lobular breast carcinoma in situ (LCIS) * Being a carrier for BRCA1 and/or BRCA2 * Predicted lifetime risk of breast cancer > 20% based on family history * Predicted 10-year risk of breast cancer of >= 2.31% * Predicted 5-year risk of breast cancer >= 1.67%
• If a female of child-bearing potential, must not be pregnant or planning to become pregnant during the study * Women < 50 years old who are of child-bearing potential must have a negative pregnancy test (urine human chorionic gonadotropin [HCG] or serum) within 14 days of enrollment
• Must have a negative mammogram or negative breast magnetic resonance imaging (MRI) within 1 year of protocol-required baseline core biopsy
• Clinical breast exam interpreted as benign (not suspicious for cancer) at Memorial Sloan Kettering (MSK)
• Performing less than or equal to 120 minutes of structured moderate-intensity or strenuous-intensity exercise per week
• Able to complete an acceptable baseline cardiopulmonary exercise testing (CPET) in the absence of high risk electrocardiography (ECG) findings or other inappropriate response to exercise as determined by the investigator
• Able to achieve an acceptable peak baseline CPET, as defined by any of the following criteria: * Achieving a plateau in oxygen consumption, concurrent with an increase in power output * A respiratory exchange ratio of >= 1.10 * Attainment of maximal predicted heart rate (HRmax) (i.e., within 10 beats per minute [bpm] of age-predicted HRmax) * Volitional exhaustion, as measured by a rating of perceived exertion (RPE) >= 18 on the BORG scale

Exclusion Criteria

• Use of any selective estrogen receptor modulator or aromatase inhibitor within 6 months of randomization, including, but not limited to: tamoxifen, raloxifene, arzoxifene, acolbifene, anastrozole, exemestane, and letrozole
• Enrollment on an interventional investigational study
• Bilateral breast implants
• Any newly identified breast abnormality requiring surgical excision
• History of any of the following: * Invasive breast cancer * Ductal breast carcinoma in situ (DCIS)
• Any current invasive cancer diagnosis
• Metastatic malignancy of any kind
• Any other condition or intercurrent illness that, in the opinion of the investigator, makes the subject a poor candidate for core biopsy or the trial
• Mental impairment leading to inability to cooperate
• Room air desaturation at rest =< 85%
• Any of the following absolute contraindications to cardiopulmonary exercise testing and/or aerobic training: * Acute myocardial Infarction (within 3-5 days of any planned study procedures) * Unstable angina * Uncontrolled arrhythmia causing symptoms or hemodynamic compromise * Recurrent syncope * Active endocarditis * Acute myocarditis or pericarditis * Symptomatic severe aortic stenosis * Uncontrolled heart failure * Acute pulmonary embolus or pulmonary infarction within 3 months of any planned study procedures * Thrombosis of lower extremities * Suspected dissecting aneurysm * Uncontrolled asthma * Pulmonary edema * Respiratory failure * Acute non-cardiopulmonary disorders that may affect exercise performance or be aggravated by exercise (i.e. infection, renal failure, thyrotoxicosis)