Zardavas D, et al. - A pooled analysis of individual patient data was performed to assess the prognostic relevance of phosphatidylinositol-4, 5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) mutations in primary breast cancer. PIK3CA mutations were shown to be significantly related to a better invasive disease-free survival (IDFS), distant disease-free survival (DDFS), and overall survival (OS), but had a lesser prognostic ability after adjustment for other prognostic factors.