RATIONALE: Studying the genes expressed in samples of tumor tissue from patients with cancer may help doctors identify biomarkers related to cancer.

PURPOSE: This research study is looking at tumor samples in patients undergoing treatment for gastrointestinal stromal tumors on clinical trial ACOSOG-Z9001.

OBJECTIVES:

Primary

• To examine polymorphisms in selected genes involved in the detoxifying/metabolizing and DNA repair pathways in relation to specific mutations and types of mutation in the c-kit gene in tumor tissue from patients with gastrointestinal tumors (GIST) undergoing treatment on clinical trial ACOSOG-Z9001.

Secondary

• To examine approximately 758 polymorphisms among candidate genes involved in detoxification/metabolism, cell cycle control, and DNA damage/repair in relation to specific mutations and types of mutation in the c-kit gene in tumor tissue from GIST patients for hypothesis generation. (exploratory)
• To conduct an exploratory analysis of the polymorphism distribution in these patients. (exploratory)
• To examine the association between the above polymorphisms and major toxicity (Grade 3/4) of adjuvant imatinib mesylate. (exploratory)

OUTLINE: Tumor samples are used for polymorphism and mutation analysis.

DISEASE CHARACTERISTICS:

• Tumor samples from patients with gastrointestinal stromal tumors enrolled on clinical trial ACOSOG-Z9001

Tumor samples from patients with gastrointestinal stromal tumors enrolled on clinical trial ACOSOG-Z9001