PIK3CA and neoplasm: PIK3CA somatic missense mutations were detected in 23/97 of TNBC (23.7%) and in 12/36 non-TNBC (33.3%), in detail, 6/15 Luminal-A-like (40%), 3/12 Luminal-B-like (25%) and 3/9 HER2-positive tumors (33.3%); among the TNBC, only one tumor harbored mutations in both exons 9 and 20.