RATIONALE: Studying samples of tissue in the laboratory from patients who received cetuximab may help doctors understand and predict how well patients will respond to treatment. PURPOSE: This research study is studying biomarkers in predicting response to cetuximab in patients with advanced colorectal cancer.
Name: mutation analysis
Name: laboratory biomarker analysis
Case-Only
There is one SNP
DISEASE CHARACTERISTICS: - Participation in CALGB-C80405 - Have KRAS WT or KRAS mut tumor - Randomized to treatment with either bevacizumab or cetuximab alone - Patients randomized to the combination therapy are not eligible - Available specimens at the PCO for BRAF mutation detection - Patient consent for use of samples DISEASE CHARACTERISTICS: - Participation in CALGB-C80405 - Have KRAS WT or KRAS mut tumor - Randomized to treatment with either bevacizumab or cetuximab alone - Patients randomized to the combination therapy are not eligible - Available specimens at the PCO for BRAF mutation detection - Patient consent for use of samples Colorectal Cancer Colorectal Neoplasms OBJECTIVES: Primary - To determine, among patients with advanced CRC, whether the effect of treatment (cetuximab vs bevacizumab) on progression-free survival (PFS) depends on tumor BRAF V600E mutational status. --- V600E ---
Secondary - To study the relationships between tumor BRAF V600E mutational status, OS, and tumor response. --- V600E ---
Previously collected formalin-fixed and paraffin-embedded baseline tumor samples are analyzed for BRAF V600E mutation. --- V600E ---