Correlation of MR Imaging Features with PIK3CA Mutation Status in Patients with Invasive Breast Cancer: A Preliminary Study

PIK3CA mutation frequency ranges from 8% to 40% in breast cancer. PIK3CA mutations have been shown to be associated with favorable clinicopathologic features including estrogen receptor positive status. In this study, we investigated whether MRI features are correlated with PIK3CA mutation status in patients with invasive breast cancer. Of the 54 patients, 20 (37%) had a PIK3CA mutation. PIK3CA mutated tumors were significantly less likely to show intratumoral T2 high signal intensity compared to wild type (P = .004). In conclusion, intratumoral signal intensity on T2-weighted MR images is significantly associated with PIK3CA mutation status.