E545K also related to the tumor recurrence in stage III cancer patients, all the three E545K mutations appeared only in relapse tumors (10.7% vs. 0.0%, P = 0.031), while E545K was rare in this cohort because of the small sample size, and which consisted a relative small proportion (23.1%, 3/13) in PIK3CA exon9 mutants, then precise conclusions on the prognostic value of E545K should be investigated more in the future. This evidence concerns the gene PIK3CA and cancer.