Inclusion Criteria:

          -  Pre or postmenopausal women with first incidence of early stage (stages 0 - III)
             breast cancer who have completed all treatment and are cancer-free, which includes
             women at high risk for developing invasive cancer i.e. having a breast biopsy positive
             for atypical ductal or lobular hyperplasia or carcinoma in situ.

          -  Age ≤ 75 years

          -  44 patients will be accrued as follows: a) 22 evaluable patients will be premenopausal
             as defined as regular menses (24-38 days) b) 22 evaluable patients will be
             postmenopausal as defined by a history of amenorrhea for at least one year or hormone
             levels (estradiol/FSH) consistent with menopause if post-hysterectomy status, or
             history of surgical/medical castration.

          -  Normal serum calcium or albumin-adjusted serum calcium between 2.0 and 2.9 mmol/L
             (8.0-11.5mg/dL).

          -  Adequate vitamin D level (25-hydroxy vitamin D level > 20 ng/mL)

          -  Currently on no active treatment for breast cancer and at least 3 months post all the
             treatments, with the exception of aromatase inhibitors (exemestane, anastrozole,
             letrozole)

          -  No prior or current use of IV bisphosphonates

          -  No current use of oral bisphosphonates

          -  Patients must have an unaffected, non-irradiated contralateral breast

          -  Significant breast density as determined by mammography and defined by the descriptive
             terms scattered fibroglandular tissue/densities, heterogeneously dense, or mostly
             dense tissue in the mammography report.

          -  Adequate renal function defined as a serum creatinine < 1.5 x ULN or CrCl > 30mL/min

          -  A willingness and ability to follow the study protocol, as indicated by provision of
             informed consent to participate

          -  Willingness to being tested for current pregnancy and use of birth control while being
             treated with denosumab (pre-menopausal women only)

        Exclusion Criteria:

          -  Age > 75 years

          -  Subject has known sensitivity to any of the products to be administered during the
             study (e.g., mammalian derived products, denosumab, calcium, or vitamin D).

          -  Patients have prior history or current evidence of osteonecrosis or osteomyelitis of
             the jaw.

          -  Patients have active dental or jaw condition which requires oral surgery, including
             tooth extraction.

          -  Patients have non-healed dental or oral surgery, including tooth extraction.

          -  Patients with planned invasive dental procedures

          -  Subject is pregnant or breast feeding, or planning to become pregnant within 5 months
             after the end of the treatment

          -  Subject is of child bearing potential and is not willing to use, in combination with
             her partner, highly effective methods of contraception or abstinence during treatment
             and for 5 months after the end of treatment

          -  Active infection with Hepatitis B, Hepatitis C, or Human Immunodeficiency virus (HIV)

          -  Any condition or disorder that compromises the ability of the subject to provide
             written informed consent and/or comply with study procedures

          -  History of claustrophobia

          -  Have electrically, magnetically, or mechanically activated implants including cardiac
             pacemaker, cochlear implants, magnetic surgical clips or prostheses.