Pregnant TREATMENT: Pregnant Any patient who is pregnant or who may have plans to become pregnant Not pregnant Pregnant Subject is pregnant or trying to become pregnant. Non-pregnant. Currently pregnant Patient is known to be pregnant Patient is pregnant Patient is pregnant Subjects must not be pregnant Subjects who are pregnant or may become pregnant Are pregnant Patient is not pregnant Pregnant Patient who is pregnant Not pregnant Not pregnant Women who are pregnant, plan to become pregnant, and/or breastfeed during the study. Not pregnant. Must agree not to become pregnant until at least months after ceasing study treatment not be pregnant Pregnant Are not pregnant and do not plan to become pregnant during the clinical trial Subjects must not be pregnant Patient is pregnant Patient is a pregnant woman Are pregnant The donor is pregnant or lactating, or was pregnant in the previous months, or intends to get pregnant during the study or within days after the last dose of study drug Pregnant Pregnant Subjects who are pregnant or may become pregnant during metformin administration Subjects who are pregnant. Females: neither pregnant nor intending to become pregnant during the course of the study, defined as: Not pregnant PHASE II: Pregnant (per patient report); if participant becomes pregnant during the course of the study, she will be removed from further participation Patient is pregnant Pregnant Are pregnant Pregnant Pregnant Pregnant Pregnant Currently pregnant Pregnant or thinking about becoming pregnant during the study period Pregnant Currently pregnant pregnant Pregnant females are ineligible; all subjects of childbearing potential will be asked if they are pregnant or could be pregnant; the patient must respond no to continue with radiation and to participate in this clinical study Pregnant Pregnant Participants who are pregnant Are pregnant or intend to become pregnant during the study period Non-pregnant Plan to become pregnant in the next two years, as mammography is not typically performed for screening pregnant women PRELIMINARY TEST: Not currently pregnant or was not pregnant in the last months Not currently pregnant or was not pregnant in the last months Pregnant or possibly pregnant Currently pregnant They do not plan to become pregnant during the study; and Being pregnant Currently pregnant. However, participants enrolled who become pregnant after randomization can remain on the study. If female, must not be pregnant, plan to become pregnant, or nurse a child during the study and through days after completion of the study Pregnant Are pregnant Currently pregnant Women who are pregnant or plan to become pregnant in the study period Participants who are pregnant Pregnant Participants who are pregnant Patient is pregnant Are pregnant Not pregnant Patient is not pregnant The subject is pregnant Pregnant Currently pregnant Participants who are pregnant Pregnant Is pregnant; Pregnant Pregnant Women who are pregnant or trying to get pregnant Not pregnant Are pregnant Pregnant Pregnant Be pregnant Patient who is pregnant Are pregnant Participants who are currently pregnant Not pregnant Women who are pregnant or intending to become pregnant during the study Currently pregnant