Patient Outcomes and <em>PIK3CA</em> Mutations

Clinical Pearls

Sara Hurvitz, MD, medical oncologist, UCLA Medical Center, discusses patient outcomes associated with PIK3CA mutations.

• A number of studies have analyzed the outcomes of patients with a PIK3CA mutation.
• Preclinical data suggest the PIK3CA mutation may make tumors resistant to trastuzumab.
• Trastuzumab-na&iuml;ve patients with HER2 amplification and a PIK3CA mutation seem to do better than those who do not. Patients with a PIK3CA mutation who are treated with trastuzumab seem to do worse.
• Patients with a PIK3CA mutation have a lower chance of having a pathologic complete response.