Biomarkers in Tissue Samples From Older Women With Breast Cancer

PIK3CA Mutation Status as a Biomarker in Elderly Women With Breast Cancer

This research trial studies phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha (PIK3CA) mutation analysis in tissue samples from older patients with stage I breast cancer. Studying samples of tissue from patients with stage I breast cancer in the laboratory may help doctors learn more about changes that occur in deoxyribonucleic acid (DNA) and identify biomarkers related to cancer.

PRIMARY OBJECTIVES:

To assess the relapse free-survival difference between patients with PIK3CA mutated and wild-type (WT) tumors and therefore validate PIK3CA mutation status as an important biomarker in women 70 years or older diagnosed with breast cancer.

OUTLINE:

Previously collected tissue samples are analyzed via mutation analysis of PIK3CA.

• Participants with stage I breast cancer (T1N0M0) and estrogen-receptor status positive or unknown
• Patients underwent lumpectomy with negative margins and were clinically node-negative