* For patients who underwent initial surgery and received adjuvant chemotherapy\r\n** Triple negative breast cancer (TNBC) patients must have been axillary node-positive (>= pN, any tumor size) or axillary node negative (pN) with invasive primary tumor pathological size > cm (>= pT)\r\n** Estrogen receptor (ER) and/or progesterone receptor (PgR) positive/human epidermal growth factor receptor (HER) negative patients must have had >= pathologically confirmed positive lymph nodes\r\n* For patients who underwent neoadjuvant chemotherapy followed by surgery\r\n** TNBC patients must have residual invasive breast cancer in the breast and/or resected lymph nodes (non-pathological complete response [pCR])\r\n** ER and/or PgR positive/HER negative patients must have residual invasive cancer in the breast and/or the resected lymph nodes (non-pCR) AND a clinical pathologic stage (CPS) & estrogen receptor status nuclear grade (EG) score >= Estrogen receptor positive (ER+) breast cancer patients must have received and progressed on fulvestrant and be post-menopausal Participant has a histologically and/or cytologically confirmed diagnosis of estrogen-receptor (ER) positive breast cancer by local laboratory. Invasive breast cancer between . cm and cm in size diagnosed by needle core biopsy, estrogen receptor positive (ER+) or estrogen receptor negative (ER-), Herneu positive or negative, tumor grade or Subjects must be estrogen receptor (ER) positive Estrogen receptor (ER)+ Her- breast cancer Estrogen receptor (ER)+ Her- breast cancer Estrogen receptor negative invasive breast carcinoma as defined as less than % stained cells Patients must have histologically or cytologically confirmed invasive breast cancer that is estrogen receptor positive (ER+) (> % staining) with radiographical or clinical evidence of metastatic disease \r\n* Measurable and/or non-measurable disease The invasive cancer must be estrogen receptor alpha (ER)-positive, defined as having ER staining by IHC in >= % of malignant tumor cells Estrogen receptor (ER) less than Allred score of or less than % positive staining cells in the invasive component of the tumor Patients who will participate in the endocrine therapy cohort must have invasive breast cancer that is estrogen receptor (ER)+ (? % ER staining by immunohistochemistry [IHC]) Documentation of histological or cytological confirmation of estrogen receptor positive (ER+) and HER negative adenocarcinoma of the breast must be available. Patients that are estrogen receptor positive (ER+) will take anti-estrogen therapy for treatment of their DCIS during vaccinations Estrogen receptor (ER)+ (ER- DCIS meeting other eligibility criteria are eligible) Patient must have histologically confirmed (by routine hematoxylin and eosin [H&E] staining) estrogen receptor (ER)-negative invasive adenocarcinoma of the breast Invasive carcinoma should be ER alpha receptor positive The invasive cancer must be estrogen receptor alpha (ER)-positive, with ER staining present in greater than % of invasive cancer cells by immunohistochemistry (IHC) Patients with estrogen receptor (ER)+ breast cancer must have received prior treatment with at least one hormone therapy Screen-detected, estrogen receptor (ER) positive DCIS of the breast proven on core needle biopsy, defined as % ER positive cells; the presence of a focus suspicious for microinvasion will be allowed; the size of the DCIS in the core biopsy sample must total mm (multiple cores can be summed) and must be estimated on the deepest step section (if step sections are taken) Have stage I-III estrogen receptor positive (ER+) breast cancer Stage I-III estrogen receptor positive breast cancer (positive for estrogen receptor [ER] with positivity defined as immunohistochemical staining in >= % of cells) on adjuvant hormonal therapy with aromatase inhibitors (anastrozole, letrozole or exemestane) The study will be conducted in women who have been diagnosed with a first primary invasive estrogen receptor (ER) positive (+) breast cancer (stages I-IIIa) who are within the first years post-treatment Documentation of histological or cytological confirmation of estrogen receptor positive (ER+) and HER negative adenocarcinoma of the breast must be available. Adult patients with a history of pathologically confirmed estrogen receptor positive (ER+) breast cancer Patients with histologic/immunochemical proof of estrogen receptor (ER)+ primary or metastatic malignancy (positive staining in >= % of cells by immunohistochemistry) PHASE I: Women with estrogen receptor (ER)+, HER-, lymph node (LN)-, breast cancers < cm who were diagnosed with a first primary breast cancer > months ago and < years ago Patients must have estrogen receptor (ER) positive, HER negative metastatic breast\n cancer (MBC) with at least one non-irradiated distant site of metastasis.