PIK3CA testing: Definition, Uses, and Clinical Overview
PIK3CA testing is a laboratory test that looks for changes (mutations) in the **PIK3CA gene**. It is most often used in oncology to help **characterize a tumor’s biology** and guide treatment planning. The test is commonly performed on **tumor tissue** from a biopsy or surgery, and sometimes on blood as a “liquid biopsy.” Results are interpreted alongside other clinical and pathology information, not on their own.