RATIONALE: Collecting and storing samples of blood from patients with cancer to study in the laboratory may help doctors learn more about changes that may occur in DNA and identify biomarkers related to cancer, and may help doctors learn how well patients will respond to treatment.

PURPOSE: This laboratory study is looking at biomarkers to predict the response to interferon therapy in patients with melanoma.

OBJECTIVES:

• Generate a comprehensive multiplexed array of melanoma-associated serological markers and validate it using serum samples from patients with melanoma and healthy control participants.
• Determine changes in the profile of serological markers induced by interferon-alfa 2b (IFN-α2b) therapy.
• Define panels of serological markers with prognostic and predictive power for IFN-α2b therapy responses in patients with melanoma.

OUTLINE: This is a multicenter study.

Serum samples are used for multiplex analyses. Biomarkers to be assessed include cytokines, chemokines, growth factors, angiogenic and antiangiogenic molecules, matrix metalloproteases (MMPs), tissue inhibitors of MMPs (TIMPs), melanoma-associated antigens, basic fibroblast growth factor, insulin-like growth factor I and II, thrombospondin, endostatin, angiostatin, vasostatin, and vascular endothelial growth factor inhibitor.

PROJECTED ACCRUAL: A total of 1,716 samples will be accrued for this study.

DISEASE CHARACTERISTICS:

• Diagnosis of melanoma OR healthy volunteer (control)

PATIENT CHARACTERISTICS:

• Not specified

PRIOR CONCURRENT THERAPY:

• Not specified

Samples submitted for research from patients participating in E1690 and E1694