RATIONALE: Studying samples of tumor tissue from patients with cancer in the laboratory may help doctors learn more about changes that occur in DNA and identify biomarkers related to cancer. It may also help doctors predict how patients will respond to treatment.

PURPOSE: This research study is looking at tumor tissue samples from patients with melanoma treated on clinical trial EST-1690.

OBJECTIVES:

• To validate the prognostic role of several biomarkers suggested by gene expression profiling and tissue microarray (TMA) studies (e.g., NCOA3, SPP1, and RGS1) on the outcome associated with melanoma in the EST-1690 cohort using IHC analysis.
• To examine the potential predictive role of such biomarkers in patients undergoing adjuvant interferon alfa therapy.
• To analyze the correlation between the intensity of biomarker expression and survival of this cohort both in the observation and in the interferon-treated groups.
• To examine the prognostic role of these biomarkers on the outcome associated with melanoma in the EST-1690 cohort using quantitative-PCR.
• To isolate RNA from the primary specimens from patients enrolled in the EST-1690 cohort to assess the expression of genes suggested by cDNA microarray and IHC analyses (e.g., NCOA3, SPP1, and RGS1) as prognostic or predictive markers.

OUTLINE: Samples from the EST-1690 cohort are obtained and analyzed for several biomarkers (i.e., NCOA3, SPP1, and RGS1) via immunohistochemistry and quantitative PCR. RNA is isolated from the specimens to assess gene expression via quantitative PCR.

DISEASE CHARACTERISTICS:

• Diagnosis of melanoma

  • No metastatic disease at diagnosis

• Treated on protocol EST-1690

• Primary tumor tissue specimens available

PATIENT CHARACTERISTICS:

• Not specified

PRIOR CONCURRENT THERAPY:

• See Disease Characteristics

Samples submitted for research from patients enrolled on E1690