RATIONALE: Studying samples of blood from patients with cancer in the laboratory may help doctors learn more about changes that occur and identify biomarkers related to cancer.

PURPOSE: This research study is looking at blood glycan biomarkers in women with stage IV breast cancer.

OBJECTIVES:

• To profile serum glycan biomarkers in women with metastatic stage IV breast cancer, healthy controls, and patients with noncancer medical illness.
• To determine whether serial serum glycan biomarkers correlate with response of metastatic disease to treatment.

OUTLINE: This is a multicenter study.

Blood is collected from patients with metastatic breast cancer, patients with noncancerous illness, and healthy volunteers. Samples are analyzed for serum glycan biomarkers by matrix-assisted laser desorption/ionization (MALDI) and Fourier transform ion-cyclotron resonance mass spectrometry (FT ICR MS) methods.

Blood samples are collected every 3 months for up to 18 months from patients with metastatic breast cancer. Patients without cancer have a single sample collected.

DISEASE CHARACTERISTICS:

• Patient or participant at the Women's Health Clinic, the Internal Medicine Clinic, or at the UC Davis Cancer Center, meeting 1 of the following criteria:

  • Diagnosis of stage IV metastatic breast cancer, receiving active treatment with chemotherapy, endocrine therapy, or targeted therapy

  • Patients/participants without cancer

    • Healthy control being seen for annual exams, meeting the following criteria:

      • No chronic disease
      • Not on regular prescribed medications

    • Patient without cancer being seen in the Internal Medicine Clinic

• Hormone receptor status not specified

PATIENT CHARACTERISTICS:

• Menopausal status not specified
• Not pregnant or breast feeding
• No other active cancer

PRIOR CONCURRENT THERAPY:

• See Disease Characteristics

Patients with metastatic breast cancer receiving active chemotherapy, endocrine therapy or targeted therapy Healthy age matched controls without chronic diseases and not on regular prescription medications Patients seen at Internal Medicine Clinic for any reason other than active, metastatic cancer