DNA in Predicting Response After Systemic Therapy in Women With Metastatic Breast Cancer

DISEASE CHARACTERISTICS:

* Meets 1 of the following criteria:

  * Histologically and/or cytologically confirmed stage IV adenocarcinoma of the breast (patient)
  * No diagnosis of an abnormal breast biopsy (including atypical ductal or lobular hyperplasia), or new diagnosis of breast cancer or breast cancer recurrence within the past five years (healthy participant)
* Evidence of disease progression AND initiating a new systemic treatment regimen with trastuzumab (Herceptin®), chemotherapy, endocrine therapy, or investigational agent(s) (patient)

  * Treatment may be given as a single agent or in combination
* Measurable or evaluable disease (patient)

  * Measurable disease is defined as ≥ 1 measurable lesion identified by RECIST criteria
  * Patients with evaluable disease only must have ≥ 1 tumor marker (e.g., carcinoembryonic antigen, CA 27-29, or CA 15-3) above normal level
* Treated brain metastases (surgery or radiation therapy) allowed provided patient has evidence of disease stability or presence of other site(s) of measurable or evaluable disease (patient)

  * No leptomeningeal disease
* Hormone receptor status not specified

PATIENT CHARACTERISTICS:

* Female
* Menopausal status not specified
* ECOG performance status 0-2
* No known cancer within the past 5 years other than basal cell or squamous cell carcinoma of the skin and/or adequately treated cervical cancer (healthy participant)
* Not pregnant or nursing

PRIOR CONCURRENT THERAPY:

* See Disease Characteristics
* Prior therapy in the preoperative, adjuvant, and/or metastatic setting allowed

  * Any number of prior regimens in any setting allowed
* No prior radiation therapy to the only site of disease unless there is evidence of post-radiation disease progression
* No selective estrogen receptor modulator or aromatase inhibitor for breast cancer prevention or therapy within the past 12 months (healthy participant)
* Prior or concurrent use of raloxifene for osteopenia or osteoporosis therapy allowed (healthy participant)
* Concurrent participation in another clinical trial, including one involving an investigational agent(s), allowed