PRIMARY OBJECTIVES:
I. To determine whether adjuvant hormonal therapy is not inferior to adjuvant chemohormonal in women whose tumors meet established clinical guidelines for adjuvant chemotherapy and fall in the "primary study group" category (Oncotype DX Recurrence Score 11-25).
II. To create a tissue and specimen bank for patients enrolled in this trial, including formalin fixed paraffin embedded tumor specimens, tissue microarrays, plasma, and deoxyribonucleic acid (DNA) obtained from peripheral blood.
SECONDARY OBJECTIVES:
I. To determine whether adjuvant hormonal therapy is sufficient treatment (i.e. 10 year distant disease-free survival of at least 95%) for women whose tumors meet established clinical guidelines for adjuvant chemotherapy and who fall into the "Secondary Study Group-1" category (Oncotype DX Recurrence Score =\< 10).
II. To compare the outcomes projected at 10 years by Adjuvant (with outcomes projected using classical pathologic information including tumor size, hormone receptor status, and histologic grade) with those made by the Genomic Health Oncotype DX test. Classical pathologic information and outcome results will also be used to create and refine models that would use classical information instead of or in combination with genomic tests.
III. To estimate failure rates as a function of recurrence score (RS) separately in the chemotherapy (arms C, D) and no chemotherapy (arms A, B) groups. The purpose of the analysis is to develop more precise estimates of the relationship between recurrence score and chemotherapy treatment effect, if any, at the upper range of the RS 11 - 25 group.
IV. To determine the prognostic significance of the Oncotype DX recurrence score and of the individual RS gene groups (proliferation gene group, human epidermal growth factor receptor \[HER\]2 gene group, estrogen receptor \[ER\] gene group, invasion gene group, and other genes).
TERTIARY OBJECTIVES:
I. To evaluate the effects of chemotherapy and hormonal therapy vs hormonal therapy alone on perceived cognitive impairment, fatigue, fear of recurrence among pre-menopausal patients, endocrine symptoms and sexual dysfunction, and overall health-related quality of life (HRQL).
II. To determine whether perceived cognitive impairment, fatigue, fear of recurrence, endocrine symptoms, and overall HRQL are similar for patients receiving chemotherapy plus hormonal therapy in secondary study group 2 as for those in the primary study group (arm D vs C).
III. To determine whether perceived cognitive impairment, fatigue, fear of recurrence, endocrine symptoms, and overall HRQL are similar for patients receiving hormonal therapy alone in secondary study group 1 as for those in the primary study group (arms A vs B).
IV. To determine whether age will be inversely associated with a fear of recurrence, independent of treatment assignment.
V. Among participants receiving hormonal treatment alone on arm A and arm B, to determine whether Oncotype DX Recurrence score will be inversely correlated with fear of recurrence.
VI. To create a biospecimen repository including plasma, serum and CellSearch cassettes containing circulating tumor cells (CTC) for evaluating determinants of late relapse, including candidate biomarkers reflecting occult tumor burden (e.g., CTCs and plasma tumor DNA) and host factors (e.g., estrogen, insulin growth factor-\[IGF\] axis, inflammation, etc).
VII. To create a biorepository of metastatic tumor samples in patients who have had a late relapse.
VIII. To determine body mass index (BMI) and comorbidity burden in patients with operable breast cancer five or more years after diagnosis.
IX. To determine whether there is a relationship between late relapse and BMI at diagnosis and at 5 years after diagnosis, and whether BMI-associated inflammatory and/or metabolic biomarkers are associated with early and late recurrence.
OUTLINE: This is a partially randomized study. Patients are assigned to 1 of 3 treatment groups.
GROUP 1 (SECONDARY STUDY GROUP 1; ONCOTYPE DX RECURRENCE SCORE \[ODRS\] =\< 10): Patients receive standard hormonal therapy (e.g., tamoxifen alone orally (PO), aromatase inhibitor \[e.g., anastrozole, letrozole, or exemestane\] alone PO, or tamoxifen PO followed by aromatase inhibitor PO) at the discretion of the treating physician for 5 or 10 years.
GROUP 2 (PRIMARY STUDY GROUP; ODRS 11-25): Patients are randomized to receive either hormonal therapy alone or combination chemotherapy and hormonal therapy.
ARM I (EXPERIMENTAL): Patients receive hormonal therapy as in Group 1 at the discretion of the treating physician.
ARM II (STANDARD): Patients receive standard combination chemotherapy at the discretion of the treating physician. Within 4 weeks after the last dose of chemotherapy, patients receive hormonal therapy as in Group 1 at the discretion of the treating physician.
GROUP 3 (SECONDARY STUDY GROUP 2; ODRS \>= 26): Patients receive combination chemotherapy as in Group 2, Arm II followed by hormonal therapy as in Group 1.
Patients in all groups who have had breast-conservation surgery are also treated with radiotherapy. Radiotherapy should begin within 4 weeks of registration for patients receiving hormonal therapy alone or within 8 weeks after completion of chemotherapy. Patients participating in National Surgical Adjuvant Breast and Bowel Project (NSABP) and/or Radiation Therapy Oncology Group (RTOG) partial irradiation trial(s) may receive partial breast radiation.
After completion of study treatment, patients are followed up every 3-6 months for 5 years and then annually for 15 years.
Inclusion Criteria:
* Patients with operable histologically confirmed adenocarcinoma of the female breast who have completed primary surgical treatment and meet the following criteria:
* ER and/or progesterone receptor (PR)-positive: Estrogen and/or progesterone receptor positive disease (as defined by local pathology laboratory)
* Negative axillary nodes: As assessed by a sentinel lymph node biopsy, an axillary dissection, or both, and as defined by the Sixth Edition of the American Joint Committee on Cancer (AJCC) staging criteria
* Tumor size 1.1-5.0 cm (or 5 mm-1.0 cm plus unfavorable histological features):
* Unfavorable features defined as intermediate or poor nuclear and/or histologic grade, or lymphovascular invasion
* NOTE: Definition of tumor size: The tumor size used for determination of eligibility is the pathologic tumor size, which is usually determined by the size of the tumor as measured by inspection of the gross specimen; if the tumor size is measured microscopically and the tumor includes ductal carcinoma in-situ, the measurement should include only the invasive component of the tumor
* The tumor must be human epidermal growth factor receptor 2 (Her2)/neu negative by either fluorescent in-situ hybridization (FISH) or immunohistochemistry (e.g. 0 or 1+ by DAKO Herceptest)
* The patient and physician must be agreeable to initiate standard chemotherapy and hormonal therapy as adjuvant therapy
* A tissue specimen from the primary breast cancer has been located and is ready to be shipped to the appropriate laboratory after consent is obtained and within 3 days following pre-registration; NOTE: For determination of the Oncotype Recurrence Score, tissue must be shipped to Genomic Health; if the Oncotype DX Recurrence Score was previously performed by Genomic Health (prior to pre-registration), tissue must be submitted to the Eastern Cooperative Oncology Group (ECOG)-American College of Radiology Imaging Network (ACRIN) Central Biorepository and Pathology Facility upon randomization
* Leukocyte count \>= 3500/mm\^3
* Platelets \>= 100,000/mm\^3
* Serum creatinine =\< 1.5 mg/dL
* Serum aspartate transaminase (AST) that is =\< 3-fold the upper institutional limits of normal
* Patients must be disease-free of prior invasive malignancies for \>= 5 years with the exception of curatively-treated basal cell or squamous cell carcinoma of the skin or carcinoma in situ of the cervix; patients with a previous ipsilateral or contralateral invasive breast cancer, or with bilateral synchronous cancers, are not eligible; patients with previous ipsilateral or contralateral ductal in situ carcinoma (DCIS) are not eligible
* Prior treatment
* Mandatory prior surgery criteria:
* Patient must pre-register within 84 days from the final surgical procedure required to adequately treat the primary tumor (please note that if margins are not clear and a resection has to be conducted after pre-registration but before randomization, the patient will be deemed to be within the 84 day window allowed by protocol and therefore eligible)
* All tumors should be removed by either a mastectomy or local excision plus an acceptable axillary procedure (i.e., sentinel lymph node biopsy, axillary dissection, or both); there must be adequate (at least 1 mm if margin width specified) tumor-free margins of resection (for invasive and ductal carcinoma in-situ) in order for the patients to be eligible; patients with lobular carcinoma in-situ involving the resection margins are eligible
* Criteria re: other prior treatments:
* No prior chemotherapy for this malignancy
* No prior radiation therapy for this malignancy; this includes no prior MammoSite Brachytherapy radiation therapy (RT)
* Hormonal therapy: Patients who develop breast cancer while receiving a selective estrogen-receptor modulator (SERM; e.g., tamoxifen, toremifene, raloxifene) or an aromatase inhibitor (e.g., anastrazole, letrozole, exemestane) for breast cancer prevention or a SERM for other indications (e.g., raloxifene for osteoporosis) are not eligible; however, patients may have received up to 8 weeks of a SERM or aromatase inhibitor for this malignancy and still be eligible for study entry
* Patients must have an anticipated life expectancy of at least 10 years
* Patients with the following medical conditions should not be enrolled on the study:
* Chronic obstructive pulmonary disease requiring treatment
* Chronic liver disease (e.g., cirrhosis, chronic active hepatitis)
* Previous history of a cerebrovascular accident
* History of congestive heart failure or other cardiac disease that would represent a contraindication to the use of an anthracycline (e.g., doxorubicin or epirubicin)
* Chronic psychiatric condition or other condition that would impair compliance with the treatment regimen
* Women must not be pregnant or breast-feeding; all females of childbearing potential must have a blood test or urine study within 2 weeks prior to pre-registration to rule out pregnancy
* Women of childbearing potential must be strongly advised to utilize an accepted and effective form of non-hormonal contraception (e.g. intrauterine device, condoms, diaphragm, abstinence)
* Patients must not have previously had the Oncotype DX Assay performed, with the exception of patients who have had the assay performed and have a recurrence score of 11-25
