Abstract
OBJECTIVE: To explore the relationship between PIK3CA mutations and clinicopathological features and prognosis in breast cancer patients. METHODS: This retrospective cohort study included 283 patients with invasive breast cancer who underwent surgery from June 2017 to June 2022. PIK3CA exon 9 and 20 mutations were detected using PCR and sequencing. Patients were divided into recurrence (n = 47) and non-recurrence (n = 236) groups based on follow-up data to identify postoperative recurrence factors and build a prediction model. Kaplan-Meier analysis was used to evaluate recurrence rates. RESULTS: PIK3CA mutations were identified in 41% of patients, with exon 20 mutations being the most common (62.1%). Mutations correlated with tumor quadrant, histological subtype, clinical stage, perineural invasion, and high NLR (p < 0.05). Recurrence group patients showed higher BMI, multiple tumors, non-luminal types, advanced clinical stage, lymph node metastasis, and higher NLR (p < 0.05). Multivariate analysis identified high BMI, multiple tumors, lymph node metastasis, advanced clinical stage, and perineural invasion as independent recurrence risk factors (p < 0.05). Notably, no significant difference in disease-free survival was observed between PIK3CA mutant and wild-type patients (p > 0.05). CONCLUSION: PIK3CA mutations are associated with specific clinicopathological features but do not significantly impact prognosis in breast cancer patients.