MKI67 and breast cancer: For very low‐risk breast cancer (T<1 cm, histologic grade I, luminal A, and Ki‐67<14%) in the ELIOT trial, IORT was associated with a similar 10‐year local recurrence rate compared with EBRT (1.3% vs. 1.5%, p = 0.45), suggesting that IORT can be safely performed in highly selected low‐risk patients.