Group-Based Lifestyle Intervention in Measuring Biomarker Levels in Participants at High Risk for Breast Cancer

Inclusion Criteria:

Women will be considered at high risk for developing breast cancer if they fulfill one of the following criteria:

A Gail model risk of >= 1.7% over 5
Claus model lifetime risk of > 20%
Tyrer-Cuzick model lifetime risk > 20%
Personal history of breast biopsy showing atypical ductal hyperplasia (ADH), atypical lobular hyperplasia (ALH) or lobular carcinoma in situ (LCIS)
Ductal carcinoma in situ (DCIS) that has been previously treated; patients must be at least 2 months from completion of primary therapy not currently on hormonal therapy
Deleterious mutation in breast cancer (BRCA)1 or BRCA2 another gene known to increase the risk of developing breast cancer
Risk assessment of 20% chance or greater of carrying a BRCA1/2 gene mutation; the BRCAPRO model will be used to assess this risk

Body mass index (BMI)

For postmenopausal women: a BMI of > 28 and < 40
For premenopausal women: a BMI of > 25 and < 40
Willingness to provide informed consent
Physically able to undertake a moderate exercise program (assessed at the clinic visit)
Participant has the ability to attend weekly group counseling sessions and subsequent clinic visits
Participant has the ability to communicate in English
Participant agrees to be randomly assigned

Exclusion Criteria:

Women who are currently engaged in more than 90 min of moderate to vigorous exercise per week at the time of recruitment
Alcohol/drug abuse or significant mental illness, as assessed by study personnel
Previous diagnosis of invasive cancer within the past 5 years (in situ breast cancer and simple basal or squamous cell carcinoma not included)
Plans to leave the geographic area within six months
Contraindications for treadmill testing or entry into a training program
Pregnant women or women planning to be pregnant in the following year will not be admitted in to the study