乳腺癌是东西方女性最常见的恶性肿瘤之一,其发病率及病死率随年上升。随着对其发生、发展过程中的分子生物学变化研究的不断深入,以肿瘤细胞信号转导通路为治疗位点的靶向治疗成为继化疗和内分泌治疗后的又一种有效的乳腺癌治疗手段。PIK3CA基因突变是在乳腺癌中除TP53抑癌基因外最常见的基因突变之一,可发生于 Breast cancer is one of the most common malignant tumors in eastern and western women. Its morbidity and mortality are increasing year by year. With the deepening of the research on the molecular biological changes in its occurrence and development, targeted therapy using tumor cell signal transduction pathway as the treatment site has become another effective treatment of breast cancer after chemotherapy and endocrine therapy means. PIK3CA gene mutation is one of the most common gene mutations in breast cancer except TP53 tumor suppressor gene, which may occur in