Monitoring Symptoms to Help Young Women Take Hormone Therapy for Stage I-III Breast Cancer, ASPEN Study

Inclusion Criteria:

• Participants must be female and have Stage I, II, or III hormone receptor positivebreast cancer based on clinical or pathologic evaluation

• Participants must have been pre- or peri-menopausal at the time of breast cancerdiagnosis by satisfying one of the following:

• had a menstrual period (by self-report) within the 12 months before breastcancer diagnosis, or

• had a serum or plasma estradiol and/or follicle stimulating hormone (FSH)concentration consistent with premenopausal status (based on institutionalstandards) within the 12 months before breast cancer diagnosis or when checkedafter breast cancer diagnosis

• Participants must have started initial treatment with standard of care oralendocrine therapy (ET) (i.e., tamoxifen, anastrozole, exemestane, or letrozole;within 14 days prior to randomization or be planning to start initial treatment withstandard of care oral ET within 14 days after randomization

• Participants who currently have ovarian function (estradiol above the postmenopausalrange) must be planning to undergo ovarian suppression or ablation concomitantlywith oral ET medication, starting before or at the same time as oral ET initiation.Participants with chemotherapy-induced amenorrhea or ovarian failure at time ofregistration must be planning to start ovarian suppression or ablation if they haverecurrence of ovarian function during study participation (circulating estradiolconcentration in the premenopausal range or recurrence of menses)

• Participants must have completed surgery for treatment of breast cancer at least 14days prior to randomization NOTE: Concomitant radiotherapy at the time ofrandomization and/or during study participation is allowed

• Participants who received chemotherapy must have finished it at least 14 days priorto randomization NOTE: Concomitant maintenance targeted or biologic therapy (e.g.,human epidermal growth factor receptor 2 [anti-HER2] therapy, poly-ADP ribosepolymerase [PARP] inhibitor therapy, CDK4/6 inhibitor therapy, osteoclast inhibitortherapy) at the time of randomization and/or during study participation is allowed

• Participants must be >= 18 years of age

• Participants must have a complete medical history within 60 days prior torandomization

• Participants must be able to complete Patient-Reported Outcome (PRO) instruments inEnglish or Spanish

Participants must:

• agree to complete PROs at all scheduled assessments and

• complete the pre-registration (baseline) PRO forms within 14 days prior torandomization

• Participants must be able to complete symptom questions on a web browser (on asmartphone, tablet, or computer) or respond via voice on a telephone in Englishor Spanish. Participants must agree to complete symptom questions at allscheduled assessments NOTE: Participants who do not have access to the internetand who cannot receive telephone calls for interactive voice response system (IVRS) assessments are not eligible

• Participants must be offered the opportunity to participate in specimen bankingfor translational medicine. With participant consent, specimens must becollected and submitted via the Southwest Oncology Group (SWOG) specimentracking system

• Participants must be informed of the investigational nature of this study andmust sign and give informed consent in accordance with institutional andfederal guidelines

Exclusion Criteria:

• Participants must not have distant metastatic breast cancer

• Participants who have started or plan to start treatment with tamoxifen during studyparticipation must not have received prior tamoxifen for treatment or prevention ofbreast cancer

• Participants who have started or plan to start treatment with an aromatase inhibitorduring study participation must not have received prior aromatase inhibitor therapyfor treatment or prevention of breast cancer

• Participants must not be taking or planning to take oral estrogen-orprogesterone-containing treatments during study participation

NOTES:

• Participants who start or plan to start treatment with an aromatase inhibitor mayhave previously received tamoxifen for prevention of breast cancer or treatment of aprior cancer

• Participants may have received prior treatment with an aromatase inhibitor forinfertility treatment

• Participants must not be planning to become pregnant during the 80 weeks of studyparticipation

• Participants must not receive additional anti-cancer treatments (i.e.,experimental therapy, immunotherapy, biologics, etc.) as part of anotherclinical trial

• Participants must not have a non-breast malignancy for which they are currentlyreceiving treatment