Criteria

• Histologic documentation of women or men with node positive, HER2 negative, anatomic stage II or III breast carcinoma and tumor size > 2 cm) and free of recurrence; if neoadjuvant therapy was received, either initial clinical stage (determined by physical and or radiologic examination) or post-operative pathologic stage can be used for eligibility purposes, with the higher stage determining eligibility for ER/PR positive tumors; histologic documentation of node positivity is required; bilateral or synchronous breast cancers are allowed as long as both cancers are HER2 negative and at least one of the cancers meets eligibility.
• If ER and PR negative, tumor must be node positive or >2 cm and node negative. Patients must be registered within 18 months of diagnosis. pN1mic is eligible.
• If ER and/or PR positive, tumor must be node positive. Patients must be registered within 10 years of diagnosis. pN1mic is eligible.
• Prior adjuvant treatment with chemotherapy and/or endocrine therapy, as determined by the treating physician, is allowed; the last dose of chemotherapy or radiation therapy must be at least 30 days prior to study registration; concurrent hormonal therapy will be allowed.
• Regular nonsteroidal anti-inflammatory drug (NSAID)/aspirin use at any dose (including baby aspirin) (defined as >= 5 days per week) is allowed if aspirin and/or NSAIDs are stopped for 30 days prior to study entry and throughout the study period; participants are encouraged to use acetaminophen for minor pain and fever.
• Eastern Cooperative Oncology Group (ECOG) performance status 0-2.
• Patients with a prior history of gastric/duodenal ulcers documented on endoscopy can be enrolled as long as the ulcers did not cause bleeding requiring a blood transfusion/major intervention; for patients who are Helicobacter pylori positive, a course of Helicobacter pylori eradication treatment must have been completed.
• No history of gastrointestinal bleeding (GI) bleeding requiring a blood transfusion, endoscopic or operative intervention.
• No history of any prior stroke (hemorrhagic or ischemic).
• No concurrent anticoagulation with warfarin or heparin/heparin analogues, clopidogrel, direct thrombin inhibitors, or direct factor XA inhibitors.
• No history of atrial fibrillation or myocardial infarction.
• No history of grade 4 hypertension, defined as hypertension resulting in life-threatening consequences (e.g., malignant hypertension, transient or permanent neurologic deficit, hypertensive crisis).
• No chronic (duration > 30 days) daily use of oral steroids.  Inhaled or topical steroids are allowed.
• No known allergy to aspirin.
• No prior invasive malignancy of any type (including ductal breast carcinoma in situ within the past 5 years except for current diagnosis of breast cancer, and any prior diagnosis of basal or squamous cell carcinoma of the skin.  Prior history of in situ carcinoma is allowed.
• Patients with a prior history of any type of breast cancer greater than 5 years from study screening may participate in this study.
• Concurrent enrollment on a non-chemotherapy treatment trial will be allowed, as long as that trial allows concurrent daily aspirin use.