Inclusion Criteria:
* Participants must have histologically or cytologically confirmed breast cancer that is human epidermal growth factor receptor 2 negative (HER2-negative) per the most recent 2018 ASCO CAP guidelines94
* Estrogen Receptor and Progesterone immunohistochemistry (IHC) status must be known; any status is eligible, but this will define in which cohort a patient will enroll:
* Additional eligibility for cohort 1: Triple negative disease- defined as IHC staining of \<10% for ER and PR per local pathology review
* Additional eligibility for cohort 2: Hormone receptor-positive disease defined as IHC for ER or PR \>/= 10% per local pathology review
* Men and women are eligible
* Age 70 and older at the time of protocol registration
* Non-metastatic, invasive breast cancer (scans are not required to document non-metastatic disease- any staging work-up is up to the treating provider's discretion)
* Recommended to have either neoadjuvant chemotherapy or adjuvant chemotherapy per their treating provider.
* Any surgery, nodal assessment, radiation, hormonal therapy is left up to the treating provider but should not occur concurrently with study therapy. If any additional chemotherapy is planned by a treating provider, this must occur AFTER all study-related chemotherapy is completed.
* Any patient receiving pre-operative hormonal therapy and who is then recommended for adjuvant chemotherapy is eligible, though hormonal therapy should be held during study treatment administration
* All study-related chemotherapy must be given prior to surgery if neoadjuvant therapy is planned or adjuvantly if postoperative chemotherapy is planned. For example, giving 6 doses pre-operatively and 6 doses postoperatively is not allowed on study.
* There are no restrictions on life expectancy, ECOG Performance Status, or baseline blood values or organ function; Appropriateness of chemotherapy treatment is left up to the treating provider but providers should be ok with the full starting doses of each agent.
* Participants must be willing to fill out surveys over time or designate a proxy to answer on their behalf.
* Ability to understand and the willingness to sign a written informed consent document.
* Patients who do not speak or read English are eligible as long as adequate interpreter services are available or the surveys are available in the preferred language (i.e. PRO surveys are available in many languages)
Exclusion Criteria:
* Participants who have already received chemotherapy for the current cancer. Prior diagnoses of breast cancers are allowed, provided that the treating provider feels that the current cancer represents a new primary breast cancer and not recurrent disease.
* Participants who are receiving any other investigational or anti-cancer agents. Any additional radiation, hormonal therapy or chemotherapy planned should be administered once the study treatments have completed.
* History of allergic reactions attributed to compounds of similar chemical or biologic composition to cyclophosphamide, carboplatin, and paclitaxel.
* Prior chemotherapy receipt is allowed in the setting of treatment of other/prior cancers, but no prior carboplatin (cohort 1), cyclophosphamide (cohort 2), or paclitaxel (both cohorts) receipt in the last 2 years is allowed (given toxicity and possible efficacy concerns
