Breast conserving surgery (BCS) with adjuvant radiation therapy showed improved prognosis compared with mastectomy for early staged triple negative breast cancer patients Running title: BCS had better prognosis than mastectomy for early TNBC patients.

: Triple-negative breast cancer (TNBC) is a subtype of breast cancer with stronger invasive capacity. For the operation strategies of early staged (stage I and stage II) TNBC patients, BCS plus radiotherapy (BCS+RT), mastectomy only (MRM only) or MRM plus radiotherapy (MRM+RT) is feasible, but no clear conclusion has been made on the choice of these treatments. : The early staged TNBC patients (stage I and stage II) from the Surveillance, Epidemiology and End Results (SEER) program database between 1973 and 2014 were included in the study.